GREY WOLF INC
8-K, 1998-05-21
DRILLING OIL & GAS WELLS
Previous: CENTENNIAL TAX EXEMPT TRUST /CO/, 497, 1998-05-21
Next: INTELLIGENT SYSTEMS CORP, 10-K405/A, 1998-05-21



<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                               ------------------

                                    FORM 8-K


                                CURRENT  REPORT


                       Pursuant to Section 13 or 15(d) of
                      the Securities Exchange Act of 1934

Date of Report: (Date of earliest event reported): May 21, 1998 (May 5, 1998)


                               GREY WOLF, INC.
           (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)




<TABLE>
<CAPTION>
<S>                            <C>                              <C>
        Texas                        1-8226                                 74-2144774
(State of Incorporation)      (Commission File Number)          (IRS Employer Identification No.)
</TABLE>



                        10370 Richmond Avenue, Suite 600
                           Houston, Texas 77042-4136
             (Address of Registrant's principal executive offices)



                                 (713) 435-6100
            (Registrant's telephone number, including area code)




                                (Not Applicable)
         (Former name or former address, if changed since last report)
<PAGE>   2
ITEM 5.  OTHER EVENTS

144A OFFERING OF $75.0 MILLION OF 8-7/8% SENIOR NOTES DUE 2007, SERIES B

         On May 5, 1998, Grey Wolf, Inc. (the "Company") entered into a
Purchase Agreement with Donaldson, Lufkin & Jenrette Securities Corporation,
Lehman Brothers Inc., and Prudential Securities Incorporated (collectively, the
"Initial Purchasers") for the purchase of an aggregate of $75.0 million of 8
7/8% Senior Notes due 2007, Series B (the "Notes").  The offering of the Notes
(the "Offering") closed on May 8, 1998.  The Notes have not been registered
under the Securities Act of 1933, as amended (the "Securities Act"), and are
subject to certain transfer restrictions.  The Notes were resold by the Initial
Purchaser pursuant to Rule 144A under the Securities Act to Qualified
Institutional Buyers, as defined in Rule 144A.

         Interest on the Notes is payable semi-annually on January 1 and July 1
of each year, commencing July 1, 1998, accruing from May 8, 1998.  The Notes
are general unsecured senior obligations of the Company, ranking pari passu in
right of payment with all indebtedness and other liabilities of the Company
that are not subordinated by their terms to other Indebtedness (as defined in
the Indenture (as defined herein)) of the Company and senior in right of
payment to all indebtedness of the Company that by its terms is so
subordinated.  The Notes will rank pari passu in right of payment with $175.0
million of 8-7/8% Senior Notes due 2007 (the "Series A Notes") issued in 1997.

         As of December 31, 1997, on a pro forma basis after giving effect to
the issuance of the Notes and the application of a portion of the net proceeds
thereof to repay amounts outstanding under the Bank Credit Facility, the
Company would have had outstanding approximately $3.2 million of secured
indebtedness.  The Indenture, dated May 8, 1998, among the Company, the
Guarantors and Chase Bank of Texas, National Association, as trustee (the
"Indenture"), permits the Company and its Subsidiaries (as defined in the
Indenture) to incur additional Indebtedness, including senior indebtedness of
up to $100.0 million aggregate principal amount which may be secured by liens
on all of the assets of the Company and its Subsidiaries, subject to certain
limitations.

GUARANTEES

         The Notes are unconditionally guaranteed (the "Guarantees"), on a
joint and several basis, by Grey Wolf Drilling Company, a Texas corporation and
wholly-owned subsidiary of the Company ("GW Drilling"); Murco Drilling
Corporation, a Delaware corporation and wholly-owned subsidiary of GW Drilling
("Murco"); Grey Wolf International, Inc., a Texas corporation and wholly-owned
subsidiary of the Company ("International"); and DI Energy, Inc., a Texas
corporation and wholly-owned subsidiary of the Company ("Energy," and with GW
Drilling, Murco, and International, collectively, the "Guarantors"), which
include all domestic, wholly-owned Subsidiaries and any other Subsidiary that
guarantees any Indebtedness of the Company and its Subsidiaries. The Guarantees
will be senior unsecured obligations of the Guarantors and will rank pari passu
in right



                                      2

<PAGE>   3
of payment with the guarantee of the Series A Notes made by such Guarantors and
all other indebtedness and liabilities of such Guarantors that are not
subordinated by their terms to other Indebtedness of such Guarantors. In
addition, the Guarantees will be effectively subordinated to secured
Indebtedness of the Guarantors, including Indebtedness under the Bank Credit
Facility, which is secured by substantially all of the assets of the three most
significant Guarantors, GW Drilling, Murco and International. The Notes will be
effectively subordinated to claims of creditors (other than the Company) of the
Company's Subsidiaries other than the Guarantors. Claims of creditors (other
than the Company) of such Subsidiaries, including trade creditors, tort
claimants, secured creditors, taxing authorities and creditors holding
guarantees, will generally have priority as to the assets of such Subsidiaries
over the claims and equity interest of the Company and, thereby indirectly, the
holders of the indebtedness of the Company, including the Notes and the
Guarantees.

REDEMPTION OR REPURCHASE OF THE NOTES

         Subject to certain limitations, the Notes will be redeemable, at the
Company's option, in whole or in part from time to time on or after July 1,
2002, at the following redemption prices, plus accrued and unpaid interest to
the redemption date:

<TABLE>
<CAPTION>
            Year                                       Percentage          
            ----                                       ----------          
            <S>                                        <C>                 
            2002                                       104.4357%           
            2003                                       102.9580%           
            2004                                       101.4792%           
            2005 and thereafter                        100.0000%           
</TABLE>

In the event the Company consummates one or more Qualified Equity Offerings (as
defined in the Indenture) on or before June 27, 2000, subject to certain
limitations, the Company at its option may use all or a portion of the net cash
proceeds from such Qualified Equity Offerings to redeem up to 30% of the
aggregate principal amount of the Notes at a redemption price equal to 108.875%
of the aggregate principal amount thereof, together with accrued and unpaid
interest to the date of redemption, provided that at least $50.0 million
aggregate principal amount of Notes remains outstanding immediately after such
redemption.

         Upon a Change of Control, each holder of Notes will have the right to
require the Company to repurchase all or any part of such holder's Notes at a
purchase price equal to 101% of the aggregate principal amount thereof, plus
accrued and unpaid interest to the date of purchase.

CERTAIN COVENANTS

         The Indenture contains covenants limiting the ability of the Company
and its Subsidiaries to, among other things, pay dividends or make other
Restricted Payments (as defined in the Indenture), incur additional
Indebtedness (as defined in the Indenture), make Investments (as defined in the
Indenture), permit Liens (as defined in the Indenture), incur dividend and
other payment restrictions affecting Subsidiaries, enter into consolidation,
merger, conveyance, lease or transfer





                                      3
<PAGE>   4
transactions, make asset sales, enter into transactions with Affiliates (as
defined in the Indenture) and engage in unrelated lines of business. In
addition, the Indenture imposes restrictions on the ability of Subsidiaries to
issue guarantees. These covenants are subject to certain exceptions and
qualifications as provided in the Indenture.

USE OF PROCEEDS

         Of  the net proceeds of the Offering:  (i) approximately $30.0 million
was applied to repay indebtedness incurred in connection with the acquisition
of Murco effected in January 1998; (ii) approximately $5.6 million is intended
to be used for refurbishment of drilling rigs, and (iii) the remainder is
expected to be used for general corporate purposes.

REGISTRATION RIGHTS

         Pursuant to a Registration Rights Agreement, dated May 8, 1998, among
the Company, the Guarantors, and the Initial Purchasers (the "Registration
Rights Agreement"), the Company and the Guarantors will (i) file a registration
statement (the "Exchange Offer Registration Statement") on or prior to 60 days
after the consummation of the Offering (the "Closing Date") with respect to an
offer to exchange the Notes for new senior notes of the Company (the "Exchange
Notes") registered under the Securities Act with terms substantially identical
to those of the Notes (the "Exchange Offer") and (ii) to use their reasonable
best efforts to cause the Exchange Offer Registration Statement to be declared
effective by the Securities and Exchange Commission (the "Commission") on or
prior to 120 days after the Closing Date.  If applicable law or interpretations
of the Commission's staff do not permit the Company and the Guarantors to
effect the Exchange Offer, or if certain holders of Notes are not permitted to
participate in, or do not receive the benefit of, the Exchange Offer, the
Company and the Guarantors will use their reasonable best efforts to cause to
become effective a shelf registration statement (the "Shelf Registration
Statement") with respect to the resale of the Notes and to keep such
registration statement effective for one year or such shorter period ending
when all of the Notes have been sold under such shelf registration statement.

         If the Company fails to meet certain deadlines and other obligations
established by the Registration Rights Agreement (a "Registration Default"),
the Company would be obliged to pay additional interest ("Special Interest") to
each holder of Notes, with respect to the first 90-day period immediately
following the occurrence of such Registration Default in an amount equal to
$.05 per week per $1,000 principal amount of Notes held by such holder.  The
amount of the Special Interest would increase by an additional $.05 per week
per $1,000 principal amount or Notes with respect to each subsequent 90-day
period until all Registration Defaults have been cured, up to a maximum amount
of Special Interest of $.25 per week per $1,000 principal amount of Notes.  All
accrued Special Interest will be paid by the Company on each interest payment
date.  Following the cure of all Registration Defaults, the accrual of Special
Interest will cease.  The right of a holder of Notes to receive Special
Interest will be the exclusive remedy and liquidated damages for any
Registration Defaults.





                                      4
<PAGE>   5
DISTRIBUTION

         The Notes were initially issued in book entry form through the
facilities of The Depository Trust Company ("DTC") which will act as depository
for the Notes. Such Notes were issued in global form and interests in Global
Notes will be shown on and transfers will be effected only through records
maintained by DTC and its participants.  The Notes sold to Qualified
Institutional Buyers (as defined in Rule 144A promulgated under the Securities
Act) are to be traded in the PORTAL market.

CONSENT SOLICITATION

         Concurrent with the Offering, the Company sought the consent of the
holders of the Series A Notes to a Second Supplemental Indenture to the
indenture under which the Series A Notes were issued (the "Series A Indenture")
to permit the Offering.  The Second Supplemental Indenture amended the
definition of "Permitted Indebtedness" under the Series A Indenture so as to
permit the Company's subsidiaries that guarantee the Series A Notes to also
guarantee (pursuant to Section 4.04 of the Series A Indenture) other
indebtedness of the Company incurred in compliance with Section 4.03 of the
Series A Indenture, which contains certain limitations of the Company's right
to incur additional indebtedness.  The principal effect of this amendment was
to enable the guarantors of the Series A Notes to also guarantee the Series B
Notes.  The Offering was closed upon receipt by the Company of executed
consents from the holders of a majority in aggregate principal amount of the
Series A Notes.

ITEM 7.  FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS

(C)      EXHIBITS

         Exhibit 4.1              Purchase Agreement, dated May 5, 1998, by and
                                  among Grey Wolf, Inc. and the Guarantors, and
                                  Donaldson, Lufkin & Jenrette Securities
                                  Corporation, Lehman Brothers Inc., and
                                  Prudential Securities Incorporated.

         Exhibit 4.2              Registration Rights Agreement, dated May 8,
                                  1998, by and among Grey Wolf, Inc., the
                                  Guarantors, and Donaldson, Lufkin & Jenrette
                                  Securities Corporation, Lehman Brothers Inc.,
                                  and Prudential Securities Incorporated.

         Exhibit 4.3              Indenture, dated May 8, 1998, by and among
                                  Grey Wolf, Inc., the Guarantors, and Chase
                                  Bank of Texas, National Association, as
                                  Trustee.

         Exhibit 4.4              Global Note, dated May 8, 1998.





                                      5
<PAGE>   6
         Exhibit 4.5              Indenture, dated as of June 27, 1997, among
                                  Grey Wolf, Inc. (formerly "DI Industries,
                                  Inc."), the Guarantors, and Chase Bank of
                                  Texas, National Association (formerly "Texas
                                  Commerce Bank National Association"), as
                                  Trustee, as amended by Supplemental
                                  Indenture, dated March 31, 1998, among Murco
                                  Drilling Corporation, Grey Wolf, Inc., the
                                  Guarantors, and Chase Bank of Texas, National
                                  Association, as Trustee, and as further
                                  amended by Second Supplemental Indenture,
                                  dated May 8, 1998, by and among Grey Wolf,
                                  Inc., the Guarantors, and Chase Bank of
                                  Texas, National Association, as Trustee.


                                   SIGNATURE

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

Date: May 19, 1998




                                       GREY WOLF, INC.




                                         /s/ David W. Wehlmann
                                       -----------------------------------------
                                         David W. Wehlmann,
                                         Senior Vice President, Chief Financial 
                                         Officer and Secretary





                                      6
<PAGE>   7
                               INDEX OF EXHIBITS


<TABLE>
<CAPTION>
Exhibit Number            Description
- --------------            -----------
<S>                       <C>
Exhibit 4.1               Purchase Agreement, dated May 5, 1998, by and among Grey Wolf, Inc. and the Guarantors, and
                          Donaldson, Lufkin & Jenrette Securities Corporation, Lehman Brothers Inc., and Prudential
                          Securities Incorporated.

Exhibit 4.2               Registration Rights Agreement, dated May 8, 1998, by and among Grey Wolf, Inc., the Guarantors,
                          and Donaldson, Lufkin & Jenrette Securities Corporation, Lehman Brothers Inc., and Prudential
                          Securities Incorporated.

Exhibit 4.3               Indenture, dated May 8, 1998, by and among Grey Wolf, Inc., the Guarantors, and Chase Bank of
                          Texas, National Association, as Trustee.

Exhibit 4.4               Global Note, dated May 8, 1998.

Exhibit 4.5               Indenture, dated as of June 27, 1997, among Grey Wolf, Inc. (formerly "DI Industries, Inc."),
                          the Guarantors, and Chase Bank of Texas, National Association (formerly "Texas Commerce Bank
                          National Association"), as Trustee, as amended by Supplemental Indenture, dated March 31, 1998,
                          among Murco Drilling Corporation, Grey Wolf, Inc., the Guarantors, and Chase Bank of Texas,
                          National Association, as Trustee, and as further amended by Second Supplemental Indenture,
                          dated May 8, 1998, by and among Grey Wolf, Inc., the Guarantors, and Chase Bank of Texas,
                          National Association, as Trustee.
</TABLE>





                                      7

<PAGE>   1
                                                                     EXHIBIT 4.1












                                 GREY WOLF, INC.
                                     AND THE
                                   GUARANTORS


                                   $75,000,000

                     8-7/8% Senior Notes due 2007, Series B

                               Purchase Agreement

                                   May 5, 1998







                          DONALDSON, LUFKIN & JENRETTE
                             SECURITIES CORPORATION

                              LEHMAN BROTHERS INC.

                       PRUDENTIAL SECURITIES INCORPORATED











<PAGE>   2







                                   $75,000,000





                     8-7/8% Senior Notes due 2007, Series B



                                 GREY WOLF, INC.



                               AND THE GUARANTORS



                               PURCHASE AGREEMENT





                                                                     May 5, 1998



DONALDSON, LUFKIN & JENRETTE

   SECURITIES CORPORATION

LEHMAN BROTHERS INC.

PRUDENTIAL SECURITIES  INCORPORATED

     c/o Donaldson, Lufkin & Jenrette

         Securities Corporation

     277 Park Avenue

     New York, New York 10172



Dear Sirs:



             Grey Wolf, Inc., a Texas corporation (the "COMPANY"),
                    proposes to issue and sell to Donaldson,




<PAGE>   3






Lufkin & Jenrette Securities Corporation ("DLJ"), Lehman Brothers Inc. and
Prudential Securities Incorporated (each, an "INITIAL PURCHASER" and,
collectively, the "INITIAL PURCHASERS") an aggregate of $75,000,000 in principal
amount of its 8-7/8% Senior Notes due 2007, Series B (the "NOTES"), subject to
the terms and conditions set forth herein. The Notes are to be issued pursuant
to the provisions of an indenture (the "INDENTURE"), to be dated as of the
Closing Date (as defined below), among the Company, the Guarantors (as defined
below) and Chase Bank of Texas, N.A., as trustee (the "TRUSTEE"). The Notes and
the Exchange Notes (as defined below) issuable in exchange therefor are
collectively referred to herein as the "NOTES." The Notes will initially be
guaranteed (the "SUBSIDIARY GUARANTEES") by each of the subsidiaries of the
Company listed on Schedule A hereto (each, a "GUARANTOR" and collectively the
"GUARANTORS"). Capitalized terms used but not defined herein shall have the
meanings given to such terms in the Indenture.



                  1. OFFERING MEMORANDUM. The Notes will be initially offered
and sold to the Initial Purchasers pursuant to one or more exemptions from the
registration requirements under the Securities Act of 1933, as amended (the
"ACT"). The Company and the Guarantors have prepared an offering memorandum,
dated May 5, 1998, relating to the Notes and the Subsidiary Guarantees (such
offering memorandum together with the information incorporated by reference
therein, being herein referred to as the "OFFERING MEMORANDUM").



                  Upon original issuance thereof, and until such time as the
same is no longer required pursuant to the Indenture, the Notes (and all
securities issued in exchange therefor, in substitution thereof or upon
conversion thereof) shall bear the following legend:



                  "THIS NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER
         THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"),
         AND, ACCORDINGLY, MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE
         TRANSFERRED WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
         BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN THE SECOND SENTENCE
         HEREOF. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST HEREIN,
         THE HOLDER (1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL
         BUYER" (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) (A "QIB") OR
         (B) IT HAS ACQUIRED THIS NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE
         WITH REGULATION S UNDER THE SECURITIES ACT OR, (2) AGREES THAT IT WILL
         NOT RESELL OR OTHERWISE TRANSFER THIS NOTE EXCEPT (A) TO THE COMPANY OR
         ANY OF ITS SUBSIDIARIES, (B) TO A PERSON WHOM THE SELLER REASONABLY
         BELIEVES IS A QIB PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF
         A QIB IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (C) IN AN
         OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR 904 OF
         REGULATION S UNDER THE SECURITIES ACT, (D) IN A TRANSACTION MEETING THE
         REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (E) IN ACCORDANCE
         WITH ANOTHER EXEMPTION FROM THE REGISTRATION


                                                                               2
<PAGE>   4






         REQUIREMENTS OF THE SECURITIES ACT (AND BASED UPON AN OPINION OF
         COUNSEL ACCEPTABLE TO THE COMPANY) OR (F) PURSUANT TO AN EFFECTIVE
         REGISTRATION STATEMENT AND, IN EACH CASE, IN ACCORDANCE WITH THE
         APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR ANY
         OTHER APPLICABLE JURISDICTION AND (3) AGREES THAT IT WILL DELIVER TO
         EACH PERSON TO WHOM THIS NOTE OR AN INTEREST HEREIN IS TRANSFERRED A
         NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. AS USED HEREIN, THE
         TERMS "OFFSHORE TRANSACTION" AND "UNITED STATES" HAVE THE MEANINGS
         GIVEN TO THEM BY RULE 902 OF REGULATION S UNDER THE SECURITIES ACT. THE
         INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO REFUSE TO
         REGISTER ANY TRANSFER OF THIS NOTE IN VIOLATION OF THE FOREGOING."



                  2. AGREEMENTS TO SELL AND PURCHASE. On the basis of the
representations, warranties and covenants contained in this Agreement, and
subject to the terms and conditions contained herein, the Company agrees to
issue and sell to the Initial Purchasers, and each Initial Purchaser agrees,
severally and not jointly, to purchase from the Company, the principal amounts
of Notes set forth opposite the name of such Initial Purchaser on Schedule B
hereto at a purchase price equal to 98% of the principal amount thereof (the
"PURCHASE PRICE").



                  3. TERMS OF OFFERING. The Initial Purchasers have advised the
Company that the Initial Purchasers will make offers (the "EXEMPT RESALES") of
the Notes purchased hereunder on the terms set forth in the Offering Memorandum,
as amended or supplemented, solely to (i) persons whom the Initial Purchasers
reasonably believe to be "qualified institutional buyers" as defined in Rule
144A under the Act ("QIBS") and (ii) to persons permitted to purchase the Notes
in offshore transactions in reliance upon Regulation S under the Act (each, a
"REGULATION S PURCHASER") (such persons specified in clauses (i) and (ii) being
referred to herein as the "ELIGIBLE PURCHASERS"). The Initial Purchasers will
offer the Notes to Eligible Purchasers initially at a price equal to 100.0% of
the principal amount thereof. Such price may be changed at any time without
notice.



                  Holders (including subsequent transferees) of the Notes will
have the registration rights set forth in the registration rights agreement (the
"REGISTRATION RIGHTS AGREEMENT"), to be dated the Closing Date, in substantially
the form of Exhibit A hereto, for so long as such Notes constitute "TRANSFER
RESTRICTED SECURITIES" (as defined in the Registration Rights Agreement).
Pursuant to the Registration Rights Agreement, the Company and the Guarantors
will agree to file with the Securities and Exchange Commission (the
"COMMISSION") under the circumstances set forth therein, (i) a registration
statement under the Act (the "EXCHANGE OFFER REGISTRATION STATEMENT") relating
to the Company's 8-7/8% Senior Notes due 2007, Series B (the "EXCHANGE NOTES"),
to be offered in exchange for the Notes (such offer to exchange being referred
to as the "EXCHANGE OFFER") and the Subsidiary Guarantees thereof and (ii) a
shelf registration statement pursuant to Rule 415 under the Act (the "SHELF
REGISTRATION STATEMENT" and, together with the Exchange Offer Registration
Statement, the "REGISTRATION STATEMENTS") relating to the resale by certain
holders of the Notes and to use its reasonable best efforts to cause such
Registration Statements to be


                                                                               3

<PAGE>   5






declared and remain effective and usable for the periods specified in the
Registration Rights Agreement and to consummate the Exchange Offer. This
Agreement, the Indenture, the Notes, the Subsidiary Guarantees, the Supplemental
Series A Indenture (as defined herein) and the Registration Rights Agreement are
hereinafter sometimes referred to collectively as the "OPERATIVE DOCUMENTS."



                  4.       DELIVERY AND PAYMENT.



                           (a) Delivery of, and payment of the Purchase Price
for, the Notes shall be made at the offices of Porter & Hedges, L.L.P. or such
other location as may be mutually acceptable. Such delivery and payment shall be
made at 9:00 a.m. Houston, Texas time, on May 8, 1998 or at such other time on
the same date or such other date as shall be agreed upon by the Initial
Purchasers and the Company in writing. The time and date of such delivery and
the payment for the Notes are herein called the "CLOSING DATE."

                           (b) One or more of the Notes in definitive global
form, registered in the name of Cede & Co., as nominee of the Depository Trust
Company ("DTC"), having an aggregate principal amount corresponding to the
aggregate principal amount of the Notes (collectively, the "GLOBAL NOTE"), shall
be delivered by the Company to the Initial Purchasers (or as the Initial
Purchasers direct) in each case with any transfer taxes thereon duly paid by the
Company against payment by the Initial Purchasers of the Purchase Price thereof
by wire transfer in same day funds to the order of the Company. The Global Note
shall be made available to the Initial Purchasers for inspection not later than
9:30 a.m., New York City time, on the business day immediately preceding the
Closing Date.



                  5.      AGREEMENTS OF THE COMPANY AND THE GUARANTORS. Each of 
the Company and the Guarantors hereby agrees with the Initial Purchasers as
follows:



                           (a) To advise the Initial Purchasers promptly and, if
requested by the Initial Purchasers, confirm such advice in writing, (i) of the
issuance by any state securities commission of any stop order suspending the
qualification or exemption from qualification of any Notes for offering or sale
in any jurisdiction designated by the Initial Purchasers pursuant to Section
5(e) hereof, or the initiation of any proceeding by any state securities
commission or any other federal or state regulatory authority for such purpose
and (ii) of the happening of any event during the period referred to in Section
5(c) below that makes any statement of a material fact made in the Offering
Memorandum untrue or that requires any additions to or changes in the Offering
Memorandum in order to make the statements therein not misleading. The Company
and the Guarantors shall use their reasonable best efforts to prevent the
issuance of any stop order or order suspending the qualification or exemption of
any Notes under any state securities or Blue Sky laws and, if at any time any
state securities commission or other federal or state regulatory authority shall
issue an order suspending the qualification or exemption of any Notes under any
state securities or Blue Sky laws, the Company and the Guarantors shall use
their reasonable best efforts to obtain the withdrawal or lifting of such order
at the earliest possible time.

                                                                               4


<PAGE>   6






                           (b) To furnish the Initial Purchasers and those
persons identified by the Initial Purchasers to the Company as many copies of
the Offering Memorandum, and any amendments or supplements thereto, as the
Initial Purchasers may reasonably request for the time period specified in
Section 5(c). Subject to the Initial Purchasers' compliance with its
representations and warranties and agreements set forth in Section 7 hereof, the
Company consents to the use of the Offering Memorandum, and any amendments and
supplements thereto required pursuant hereto, by the Initial Purchasers in
connection with Exempt Resales.



                           (c) Prior to the sale of all Notes pursuant to Exempt
Resales as contemplated hereby, (i) not to make any amendment or supplement to
the Offering Memorandum of which the Initial Purchasers shall not previously
have been advised or to which the Initial Purchasers shall reasonably object
after being so advised and (ii) to prepare promptly upon the Initial Purchasers'
reasonable request, any amendment or supplement to the Offering Memorandum which
may be necessary or advisable in connection with such Exempt Resales.



                           (d) If, during the period referred to in Section 5(c)
above, any event shall occur or condition shall exist as a result of which, in
the judgment of the Company and the Guarantors or in the opinion of counsel to
the Initial Purchasers, it becomes necessary to amend or supplement the Offering
Memorandum in order to make the statements therein, in the light of the
circumstances when such Offering Memorandum is delivered to an Eligible
Purchaser, not misleading, or if, in the opinion of counsel to the Initial
Purchasers, it is necessary to amend or supplement the Offering Memorandum to
comply with any applicable law, forthwith to prepare an appropriate amendment or
supplement to such Offering Memorandum so that the statements therein, as so
amended or supplemented, will not, in the light of the circumstances when it is
so delivered, be misleading, or so that such Offering Memorandum will comply
with applicable law, and to furnish to the Initial Purchasers and such other
persons as the Initial Purchasers may designate such number of copies thereof as
the Initial Purchasers may reasonably request.



                           (e) Prior to the sale of all Notes pursuant to Exempt
Resales as contemplated hereby, to cooperate with the Initial Purchasers and
counsel to the Initial Purchasers in connection with the registration or
qualification of the Notes for offer and sale to the Initial Purchasers and
pursuant to Exempt Resales under the securities or Blue Sky laws of such
jurisdictions as the Initial Purchasers may request and to continue such
registration or qualification in effect so long as required for Exempt Resales
and to file such consents to service of process or other documents as may be
necessary in order to effect such registration or qualification; provided,
however, that neither the Company nor any Guarantor shall be required in
connection therewith to qualify as a foreign corporation in any jurisdiction in
which it is not now so qualified or to take any action that would subject it to
general consent to service of process or taxation other than as to matters and
transactions relating to the Offering Memorandum or Exempt Resales, in any
jurisdiction in which it is not now so subject.



                           (f) So long as the Notes are outstanding, (i) to mail
and make generally

                                                                               5


<PAGE>   7






available as soon as practicable after the end of each fiscal year to the record
holders of the Notes a financial report of the Company and its subsidiaries on a
consolidated basis, all such financial reports to include a consolidated balance
sheet, a consolidated statement of operations, a consolidated statement of cash
flows and a consolidated statement of shareholders' equity as of the end of and
for such fiscal year, together with comparable information as of the end of and
for the preceding year, certified by the Company's independent public
accountants and (ii) to mail and make generally available as soon as practicable
after the end of each quarterly period (except for the last quarterly period of
each fiscal year) to such holders, a consolidated balance sheet, a consolidated
statement of operations and a consolidated statement of cash flows as of the end
of and for such period, and for the period from the beginning of such year to
the close of such quarterly period, together with comparable information for the
corresponding periods of the preceding year.



                           (g) So long as the Notes are outstanding, to furnish
to the Initial Purchasers as soon as available copies of all reports or other
communications furnished by the Company or any of the Guarantors to its security
holders or furnished to or filed with the Commission or any national securities
exchange on which any class of securities of the Company or any of the
Guarantors is listed and such other publicly available information concerning
the Company and/or its subsidiaries as the Initial Purchasers may reasonably
request.



                           (h) So long as any of the Notes remain outstanding
and during any period in which the Company and the Guarantors are not subject to
Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended (the
"EXCHANGE ACT"), to make available to any holder of Notes in connection with any
sale thereof and any prospective purchaser of such Notes from such holder, the
information ("RULE 144A INFORMATION") required by Rule 144A(d)(4) under the Act.



                           (i) Whether or not the transactions contemplated in
this Agreement are consummated or this Agreement is terminated, to pay or cause
to be paid all expenses incident to the performance of the obligations of the
Company and the Guarantors under this Agreement, including: (i) the fees,
disbursements and expenses of counsel to the Company and the Guarantors and
accountants of the Company and the Guarantors in connection with the sale and
delivery of the Notes to the Initial Purchasers and pursuant to Exempt Resales,
and all other fees and expenses in connection with the preparation, printing,
filing and distribution of the Offering Memorandum and all amendments and
supplements to any of the foregoing (including financial statements), including
the mailing and delivering of copies thereof to the Initial Purchasers and
persons designated by them in the quantities specified herein, (ii) all costs
and expenses related to the transfer and delivery of the Notes to the Initial
Purchasers and pursuant to Exempt Resales, including any transfer or other taxes
payable thereon, (iii) all costs of printing or reproducing this Agreement, the
other Operative Documents and any other agreements or documents in connection
with the offering, purchase, sale or delivery of the Notes, (iv) all expenses in
connection with the registration or qualification of the Notes and the
Subsidiary Guarantees for offer and sale under the securities or Blue Sky laws
of the several states and all costs of printing or producing any preliminary and
supplemental Blue Sky memoranda in connection therewith (including the filing
fees and fees and disbursements of counsel for the Initial Purchasers in
connection with such registration or qualification and memoranda relating
thereto), (v) the cost of printing certificates representing the Notes and the
Subsidiary Guarantees, (vi) all expenses and

                                                                               6


<PAGE>   8






listing fees in connection with the application for quotation of the Notes in
the National Association of Securities Dealers, Inc. ("NASD") Automated
Quotation System - PORTAL ("PORTAL"), (vii) the fees and expenses of the Trustee
and the Trustee's counsel in connection with the Indenture, the Notes and the
Subsidiary Guarantees, (viii) the costs and charges of any transfer agent,
registrar and/or depositary (including DTC), (ix) any fees charged by rating
agencies for the rating of the Notes, (x) all costs and expenses of the Exchange
Offer and any Registration Statement, as set forth in the Registration Rights
Agreement, and (xi) and all other costs and expenses incident to the performance
of the obligations of the Company and the Guarantors hereunder for which
provision is not otherwise made in this Section.



                           (j) To use its reasonable best efforts to effect the
inclusion of the Notes in PORTAL and to maintain the listing of the Notes on
PORTAL for so long as the Notes are outstanding.



                           (k) To obtain the approval of DTC for "book-entry"
transfer of the Notes, and to comply with all of its agreements set forth in the
representation letters of the Company and the Guarantors to DTC relating to the
approval of the Notes by DTC for "book-entry" transfer.



                           (l) During the period beginning on the date hereof
and continuing to and including the Closing Date, not to offer, sell, contract
to sell or otherwise transfer or dispose of any debt securities of the Company
or any Guarantor or any warrants, rights or options to purchase or otherwise
acquire debt securities of the Company or any Guarantor substantially similar to
the Notes and the Subsidiary Guarantees (other than (i) the Notes and the
Subsidiary Guarantees and (ii) commercial paper issued in the ordinary course of
business), without the prior written consent of the Initial Purchasers.



                           (m) Not to sell, offer for sale or solicit offers to
buy or otherwise negotiate in respect of any security (as defined in the Act)
that would be integrated with the sale of the Notes to the Initial Purchasers or
pursuant to Exempt Resales in a manner that would require the registration of
any such sale of the Notes under the Act.



                           (n) Not to voluntarily claim, and to actively resist
any attempts to claim, the benefit of any usury laws against the holders of any
Notes and the related Subsidiary Guarantees.



                           (o) To file an Exchange Offer Registration Statement
and to use its reasonable best efforts to have the Exchange Offer Registration
Statement declared effective, all in accordance with and subject to the terms of
the Registration Rights Agreement, to permit Exchange Notes and guarantees
thereof by the Guarantors registered pursuant to the Act to be offered in
exchange for the Notes and the Subsidiary Guarantees and to comply with all
applicable federal and state securities laws in connection with the Exchange
Offer.

                                                                               7


<PAGE>   9






                           (p) To comply with all of its agreements set forth in
the Registration Rights Agreement.



                           (q) To use its reasonable best efforts to do and
perform all things required or necessary to be done and performed under this
Agreement by it prior to the Closing Date and to satisfy all conditions
precedent to the delivery of the Notes and the Subsidiary Guarantees.





                  6. REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF THE COMPANY
AND THE GUARANTORS. As of the date hereof, each of the Company and the
Guarantors represents and warrants to, and agrees with, the Initial Purchasers
that:



                           (a) The Offering Memorandum does not, and any
supplement or amendment to it will not, contain any untrue statement of a
material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, except that the representations and
warranties contained in this paragraph (a) shall not apply to statements in or
omissions from the Offering Memorandum (or any supplement or amendment thereto)
based upon information relating to the Initial Purchasers furnished to the
Company in writing by the Initial Purchasers expressly for use therein. No stop
order preventing the use of the Offering Memorandum, or any amendment or
supplement thereto, or any order asserting that any of the transactions
contemplated by this Agreement are subject to the registration requirements of
the Act, has been issued.



                           (b) Each of the Company, the Guarantors and their
subsidiaries has been duly organized, is validly existing as a corporation,
limited liability company or limited partnership in good standing under the laws
of its jurisdiction of incorporation or formation and has the requisite power
and authority to carry on its business as described in the Offering Memorandum
and to own, lease and operate its properties, and each is duly qualified and is
in good standing as a foreign corporation authorized to do business in each
jurisdiction in which the nature of its business or its ownership or leasing of
property requires such qualification, except where the failure to be so
qualified would not have a material adverse effect on the business, prospects,
financial condition or results of operations of the Company and its
subsidiaries, taken as a whole, or draw into question the validity of this
Agreement or the other Operative Documents (a "MATERIAL ADVERSE EFFECT").



                           (c) All outstanding shares of capital stock of the
Company have been duly authorized and validly issued and are fully paid and
non-assessable.



                           (d) The entities listed on Schedule C hereto are the
only subsidiaries, direct or

                                                                               8


<PAGE>   10






indirect, of the Company. All of the outstanding shares of capital stock of, or
ownership interests in, each of the Company's subsidiaries have been duly
authorized and validly issued and are fully paid and non-assessable, and are
owned by the Company, directly or indirectly through one or more subsidiaries,
free and clear of any security interest, claim, lien, encumbrance or adverse
interest of any nature (each, a "LIEN") except for Liens described in the
Offering Memorandum.



                           (e) This Agreement has been duly authorized, executed
and delivered by the Company and each of the Guarantors.



                           (f) The Indenture and the Series A Supplemental
Indenture have been duly authorized by the Company and each of the Guarantors
and, on the Closing Date, will have been validly executed and delivered by the
Company and each of the Guarantors. When the Indenture and the Series A
Supplemental Indenture have been duly executed and delivered by the Company and
each of the Guarantors, the Indenture and the Series A Supplemental Indenture
will be a valid and binding agreement of the Company and each Guarantor,
enforceable against the Company and each Guarantor in accordance with its terms
except as (i) the enforceability thereof may be limited by bankruptcy,
insolvency, fraudulent conveyance, moratorium or similar laws now or hereafter
in effect relating to or affecting creditors' rights generally and (ii) rights
of acceleration and the availability of equitable remedies may be limited by
equitable principles of general applicability (regardless of whether such rights
and remedies are sought to be enforced at law or in equity). On the Closing
Date, the Indenture will conform in all material respects to the requirements of
the Trust Indenture Act of 1939, as amended (the "TIA" or "TRUST INDENTURE
ACT"), and the rules and regulations of the Commission applicable to an
indenture which is qualified thereunder.



                           (g) The Notes have been duly authorized and, on the
Closing Date, will have been validly executed and delivered by the Company. When
the Notes have been issued, executed and authenticated in accordance with the
provisions of the Indenture and delivered to and paid for by the Initial
Purchasers in accordance with the terms of this Agreement, the Notes will be
entitled to the benefits of the Indenture and will be valid and binding
obligations of the Company, enforceable in accordance with their terms except as
(i) the enforceability thereof may be limited by bankruptcy, insolvency,
fraudulent conveyance, moratorium or similar laws now or hereafter in effect
relating to or affecting creditors' rights generally and (ii) rights of
acceleration and the availability of equitable remedies may be limited by
equitable principles of general applicability (regardless of whether such rights
and remedies are sought to be enforced at law or in equity). On the Closing
Date, the Notes will conform as to legal matters to the description thereof
contained in the Offering Memorandum, in all material respects.



                           (h) On the Closing Date, the Exchange Notes will have
been duly authorized by the Company. When the Exchange Notes are issued,
executed and authenticated in accordance with the terms of the Exchange Offer
and the Indenture, the Exchange Notes will be entitled to the benefits of the
Indenture and will be the valid and binding obligations of the Company,
enforceable against the Company in accordance with their terms, except as (i)
the enforceability thereof may be limited by bankruptcy,

                                                                               9


<PAGE>   11






insolvency, fraudulent conveyance, moratorium or similar laws now or hereafter
in effect relating to or affecting creditors' rights generally and (ii) rights
of acceleration and the availability of equitable remedies may be limited by
equitable principles of general applicability (regardless of whether such rights
and remedies are sought to be enforced at law or in equity).



                           (i) The Subsidiary Guarantee arising under the
Indenture of each Guarantor has been duly authorized by such Guarantor and, on
the Closing Date, will have been duly executed and delivered by each such
Guarantor. When the Notes have been issued, executed and authenticated in
accordance with the Indenture and delivered to and paid for by the Initial
Purchasers in accordance with the terms of this Agreement, the Subsidiary
Guarantee of each Guarantor will be entitled to the benefits of the Indenture
and will be the valid and binding obligation of such Guarantor, enforceable
against such Guarantor in accordance with its terms, except as (i) the
enforceability thereof may be limited by bankruptcy, insolvency, fraudulent
conveyance, moratorium or similar laws now or hereafter in effect relating to or
affecting creditors' rights generally and (ii) rights of acceleration and the
availability of equitable remedies may be limited by equitable principles of
general applicability (regardless of whether such rights and remedies are sought
to be enforced at law or in equity). On the Closing Date, the Subsidiary
Guarantees to be endorsed on the Notes will conform as to legal matters to the
description thereof contained in the Offering Memorandum, in all material
respects.



                           (j) The Subsidiary Guarantee arising under the
Indenture of by each Guarantor has been duly authorized by such Guarantor and,
when issued, will have been duly executed and delivered by each such Guarantor.
When the Exchange Notes have been issued, executed and authenticated in
accordance with the terms of the Exchange Offer and the Indenture, the
Subsidiary Guarantee of each Guarantor will be entitled to the benefits of the
Indenture and will be the valid and binding obligation of such Guarantor,
enforceable against such Guarantor in accordance with its terms, except as (i)
the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent
conveyance, moratorium or similar laws now or hereafter in effect relating to or
affecting creditors' rights generally and (ii) rights of acceleration and the
availability of equitable remedies may be limited by equitable principles of
general applicability. When the Exchange Notes are issued, authenticated and
delivered, the Subsidiary Guarantees to be endorsed on the Exchange Notes will
conform as to legal matters to the description thereof in the Offering
Memorandum, in all material respects.



                           (k) The Registration Rights Agreement has been duly
authorized by the Company and each of the Guarantors and, on the Closing Date,
will have been duly executed and delivered by the Company and each of the
Guarantors. When the Registration Rights Agreement has been duly executed and
delivered, the Registration Rights Agreement will be a valid and binding
agreement of the Company and each of the Guarantors, enforceable against the
Company and each Guarantor in accordance with its terms except as (i) the
enforceability thereof may be limited by bankruptcy, insolvency, fraudulent
conveyance, moratorium or similar laws now or hereafter in effect relating to or
affecting creditors' rights generally and (ii) rights of acceleration and the
availability of equitable remedies may be limited by equitable principles of
general applicability (regardless of whether such rights and remedies are sought
to be enforced at law or in equity). On the Closing Date, the Registration
Rights Agreement will conform as to legal

                                                                              10


<PAGE>   12






matters to the description thereof in the Offering Memorandum, in all material
respects.



                           (l) Neither the Company nor any of its subsidiaries
is in violation of its respective charter or by-laws or in default in the
performance of any obligation, agreement, covenant or condition contained in any
indenture, loan agreement, mortgage, lease or other agreement or instrument, the
violation which would have a Material Adverse Effect, to which the Company or
any of its subsidiaries is a party or by which the Company or any of its
subsidiaries or their respective property is bound.



                           (m) The execution, delivery and performance of this
Agreement and the other Operative Documents by the Company and each of the
Guarantors, compliance by the Company and each of the Guarantors with all
provisions hereof and thereof and the consummation of the transactions
contemplated hereby and thereby will not (i) require any consent, approval,
authorization or other order of, or qualification with, any court or
governmental body or agency (except such as may be required under the securities
or Blue Sky laws of the various states), except for such consents, approvals,
authorizations or orders that have been, or will be, obtained prior to Closing,
(ii) conflict with or constitute a breach of any of the terms or provisions of,
or a default under, the charter or by-laws of the Company or any of its
subsidiaries or any indenture, loan agreement, mortgage, lease or other
agreement or instrument that is material to the Company and its subsidiaries,
taken as a whole, to which the Company or any of its subsidiaries is a party or
by which the Company or any of its subsidiaries or their respective property is
bound, except for such conflicts or breaches that have been, or will be, waived
prior to Closing or would not have a Material Adverse Effect, (iii) violate or
conflict with any applicable law or any rule, regulation, judgment, order or
decree of any court or any governmental body or agency having jurisdiction over
the Company, any of its subsidiaries or their respective property except for
matters of non-compliance that would not have a Material Adverse Effect, (iv)
result in the imposition or creation of (or the obligation to create or impose)
a Lien under, any agreement or instrument to which the Company or any of its
subsidiaries is a party or by which the Company or any of its subsidiaries or
their respective property is bound, or (v) result in the termination, suspension
or revocation of any Authorization (as defined below) of the Company or any of
its subsidiaries or result in any other impairment of the rights of the holder
of any such Authorization.



                           (n) There are no legal or governmental proceedings
pending or, to the Company's knowledge, threatened to which the Company or any
of its subsidiaries is or could be a party or to which any of their respective
property is or could be subject, which could reasonably be expected to result,
singly or in the aggregate, in a Material Adverse Effect.



                           (o) Neither the Company nor any of its subsidiaries
has violated any foreign, federal, state or local law or regulation relating to
the protection of human health and safety, the environment or hazardous or toxic
substances or wastes, pollutants or contaminants ("ENVIRONMENTAL LAWS"), any
provisions of the Employee Retirement Income Security Act of 1974, as amended
("ERISA"), or any provisions of the Foreign Corrupt Practices Act or the rules
and regulations promulgated thereunder, except

                                                                              11


<PAGE>   13






for such violations which, singly or in the aggregate, would not have a Material
Adverse Effect.



                           (p) There are no costs or liabilities associated with
Environmental Laws (including, without limitation, any capital or operating
expenditures required for clean-up, closure of properties or compliance with
Environmental Laws or any Authorization, any related constraints on operating
activities and any potential liabilities to third parties) which would, singly
or in the aggregate, have a Material Adverse Effect.



                           (q) Each of the Company, the Guarantors and their
respective subsidiaries has such permits, licenses, consents, exemptions,
franchises, authorizations of governmental or regulatory authorities
("PERMITS"), including, without limitation, under any applicable Environmental
Laws, as are necessary to own, lease and operate its respective properties, and
to conduct its business and is in compliance with all terms and conditions
thereof; and no event has occurred which allows or, after notice or lapse of
time or both, would allow, revocation or termination of such permits or results
or, after notice or lapse of time or both, would result in any other impairment
of the rights of the holder of any such permit; and such permits contain no
restrictions that are burdensome to the Company, the Guarantors or any of their
respective subsidiaries; except where such failure to have, or comply with the
terms or conditions of, such permits, the occurrence of any such event or the
presence of any such restriction would not, singly or in the aggregate, have a
Material Adverse Effect.



                           (r) The accountants, KPMG Peat Marwick LLP, that have
certified the financial statements incorporated by reference in the Offering
Memorandum for the years ended December 31, 1995, 1996 and 1997 are independent
public accountants with respect to the Company and the Guarantors, as required
by the Act and the Exchange Act.



                           (s) The historical financial statements, together
with related schedules and notes incorporated by reference in the Offering
Memorandum (and any amendment or supplement thereto), present fairly the
consolidated financial position, results of operations and changes in financial
position of the Company and its subsidiaries on the basis stated in the Offering
Memorandum at the respective dates or for the respective periods to which they
apply; such statements and related schedules and notes have been prepared in
accordance with generally accepted accounting principles consistently applied
throughout the periods involved, except as disclosed therein; and the other
financial and statistical information and data incorporated by reference in the
Offering Memorandum (and any amendment or supplement thereto) are, in all
material respects, accurately presented and prepared on a basis consistent with
such financial statements and the books and records of the Company.



                           (t) The pro forma financial data included in the
Offering Memorandum have been prepared on a basis consistent with the historical
financial statements of the Company and its subsidiaries and give effect to
assumptions used in the preparation thereof on a reasonable basis and in good

                                                                              12


<PAGE>   14






faith and present fairly the historical and proposed transactions contemplated
by the Offering Memorandum.



                           (u) The Company is not and, after giving effect to
the offering and sale of the Notes and the application of the net proceeds
thereof as described in the Offering Memorandum, will not be, an "investment
company," as such term is defined in the Investment Company Act of 1940, as
amended.



                           (v) There are no contracts, agreements or
understandings between the Company or any Guarantor and any person granting such
person the right to require the Company or such Guarantor to include such
person's securities with the Notes and Subsidiary Guarantees registered pursuant
to any Registration Statement.



                           (w) Neither the Company nor any of its subsidiaries
nor any agent thereof acting on the behalf of them has taken, and none of them
will take, any action that might cause this Agreement or the issuance or sale of
the Notes to violate Regulation G (12 C.F.R. Part 207), Regulation T (12 C.F.R.
Part 220), Regulation U (12 C.F.R. Part 221) or Regulation X (12 C.F.R. Part
224) of the Board of Governors of the Federal Reserve System.



                           (x) No "nationally recognized statistical rating
organization" as such term is defined for purposes of Rule 436(g)(2) under the
Act (i) has imposed (or has informed the Company or any Guarantor that it is
considering imposing) any condition (financial or otherwise) on the Company's or
any Guarantor's retaining any rating assigned to the Company or any Guarantor,
any securities of the Company or any Guarantor or (ii) has indicated to the
Company or any Guarantor that it is considering (a) the downgrading, suspension,
or withdrawal of, or any review for a possible change that does not indicate the
direction of the possible change in, any rating so assigned or (b) any change in
the outlook for any rating of the Company, any Guarantor or any securities of
the Company or any Guarantor.



                           (y) Since the respective dates as of which
information is given in the Offering Memorandum other than as set forth in the
Offering Memorandum (exclusive of any amendments or supplements thereto
subsequent to the date of this Agreement), (i) there has not occurred any change
having a Material Adverse Effect or any development that could reasonably be
expected to have a Material Adverse Effect, (ii) there has not been any material
adverse change or any development involving a prospective material adverse
change in the capital stock or in the long-term debt of the Company or any of
its subsidiaries and (iii) neither the Company nor any of its subsidiaries has
incurred any liability or obligation, direct or contingent, except as did not,
or could be reasonably expected not to have, a Material Adverse Effect.



                           (z) The Offering Memorandum, as of its date, contains
all the information specified in, and meeting the requirements of, Rule
144A(d)(4) under the Act.

                                                                              13


<PAGE>   15






                           (aa) When the Notes and the Subsidiary Guarantees are
issued and delivered pursuant to this Agreement, neither the Notes nor the
Subsidiary Guarantees will be of the same class (within the meaning of Rule 144A
under the Act) as any security of the Company or the Guarantors that is listed
on a national securities exchange registered under Section 6 of the Exchange Act
or that is quoted in a United States automated inter-dealer quotation system.



                           (bb) No form of general solicitation or general
advertising (as defined in Regulation D under the Act) was used by the Company,
the Guarantors or any of their respective representatives (other than the
Initial Purchasers, as to whom the Company and the Guarantors make no
representation) in connection with the offer and sale of the Notes contemplated
hereby, including, but not limited to, articles, notices or other communications
published in any newspaper, magazine, or similar medium or broadcast over
television or radio, or any seminar or meeting whose attendees have been invited
by any general solicitation or general advertising. No securities of the same
class as the Notes have been issued and sold by the Company within the six-month
period immediately prior to the date hereof.



                           (cc) Prior to the effectiveness of any Registration
Statement, the Indenture is not required to be qualified under the TIA.



                           (dd) None of the Company, the Guarantors nor any of
their respective affiliates or any person acting on its or their behalf (other
than the Initial Purchasers, as to whom the Company and the Guarantors make no
representation) has engaged or will engage in any directed selling efforts
within the meaning of Regulation S under the Act ("REGULATION S") with respect
to the Notes or the Subsidiary Guarantees.



                           (ee) The sale of the Notes pursuant to Regulation S
is not part of a plan or scheme to evade the registration provisions of the Act.



                           (ff) The Company, the Guarantors and their respective
affiliates and all persons acting on their behalf (other than the Initial
Purchasers, as to whom the Company and the Guarantors make no representation)
have complied with and will comply with the offering restrictions requirements
of Regulation S in connection with the offering of the Notes outside the United
States and, in connection therewith, the Offering Memorandum will contain the
disclosure required by Rule 902(h).



                           (gg) The Company is a "reporting issuer," as defined
in Rule 902 under the Act.



                           (hh) Assuming the accuracy of the Initial Purchasers'
representations and warranties and agreements set forth in Section 7 hereof, no
registration under the Act of the Notes or the

                                                                              14


<PAGE>   16






Subsidiary Guarantees is required for the sale of the Notes and the Subsidiary
Guarantees to the Initial Purchasers as contemplated hereby or for the Exempt
Resales.



                           (ii) Each certificate signed by any officer of the
Company or any Guarantor and delivered to the Initial Purchasers or counsel for
the Initial Purchasers shall be deemed to be a representation and warranty by
the Company or such Guarantor to the Initial Purchasers as to the matters
covered thereby.



                           (jj) The Company and its subsidiaries have good and
indefeasible title in fee simple to all real property and good and marketable
title to all personal property owned by them which is material to the business
of the Company and its subsidiaries, in each case free and clear of all Liens
and defects, except such as are described in the Offering Memorandum or such as
do not materially affect the value of such property and do not interfere with
the use made and proposed to be made of such property by the Company and its
subsidiaries; and any real property and buildings held under lease by the
Company and its subsidiaries are held by them under valid, subsisting and
enforceable leases with such exceptions as are not material and do not interfere
with the use made and proposed to be made of such property and buildings by the
Company and its subsidiaries, in each case except as described in the Offering
Memorandum.



                           (kk) The Company and its subsidiaries own or possess,
or can acquire on reasonable terms, all licenses, inventions, copyrights,
know-how (including trade secrets and other unpatented and/or unpatentable
proprietary or confidential information, systems or procedures), trademarks,
service marks and trade names ("INTELLECTUAL PROPERTY") currently employed by
them in connection with the business now operated by them except where the
failure to own or possess or otherwise be able to acquire such intellectual
property would not, singly or in the aggregate, have a Material Adverse Effect;
and neither the Company nor any of its subsidiaries has received any notice of
infringement of or conflict with asserted rights of others with respect to any
of such intellectual property which, singly or in the aggregate, if the subject
of an unfavorable decision, ruling or finding, would have a Material Adverse
Effect.



                           (ll) The Company and each of its subsidiaries are
insured by insurers of recognized financial responsibility against such losses
and risks and in such amounts as are prudent and customary in the businesses in
which they are engaged; and neither the Company nor any of its subsidiaries (i)
has received notice from any insurer or agent of such insurer that substantial
capital improvements or other material expenditures will have to be made in
order to continue such insurance or (ii) has any reason to believe that it will
not be able to renew its existing insurance coverage as and when such coverage
expires or to obtain similar coverage from similar insurers at a cost that would
not have a Material Adverse Effect.



                           (mm) There is no (i) significant unfair labor
practice complaint, grievance or arbitration proceeding pending or, to the
Company's knowledge, threatened against the Company or any of its subsidiaries
before the National Labor Relations Board or any state or local labor relations
board, (ii) strike, labor dispute, slowdown or stoppage pending or, to the
Company's knowledge, threatened against the

                                                                              15


<PAGE>   17






Company or any of its subsidiaries or (iii) union representation question
existing with respect to the employees of the Company or any of its
subsidiaries, except in the case of clauses (i), (ii) and (iii) for such actions
which, singly or in the aggregate, could not reasonably be expected to have a
Material Adverse Effect. To the knowledge of the Company, no collective
bargaining organizing activities are taking place with respect to the Company or
any of its subsidiaries.



                           (nn) The Company and each of its subsidiaries
maintains a system of internal accounting controls sufficient to provide
reasonable assurance that (i) transactions are executed in accordance with
management's general or specific authorizations; (ii) transactions are recorded
as necessary to permit preparation of financial statements in conformity with
generally accepted accounting principles and to maintain asset accountability;
(iii) access to assets is permitted only in accordance with management's general
or specific authorization; and (iv) the recorded accountability for assets is
compared with the existing assets at reasonable intervals and appropriate action
is taken with respect to any differences.



                           (oo) All material tax returns required to be filed by
the Company and each of its subsidiaries in any jurisdiction have been filed,
other than those filings being contested in good faith, and all material taxes,
including withholding taxes, penalties and interest, assessments, fees and other
charges due pursuant to such returns or pursuant to any assessment received by
the Company or any of its subsidiaries have been paid, other than those being
contested in good faith and for which adequate reserves have been provided.



                           (pp) The indebtedness represented by the Notes is
being incurred for proper purposes and in good faith, and each of the Company
and the Guarantors was, at the time of the incurrence of such indebtedness that
will be repaid with the proceeds of the issuance and sale of the Notes, and will
be on the Closing Date (after giving effect to the application of the proceeds
from the issuance of the Notes) solvent and had, at the time of the incurrence
of such indebtedness that will be repaid with the proceeds of the issuance and
sale of the Notes, and will have on the Closing Date (after giving effect to the
application of the proceeds from the issuance of the Notes) sufficient capital
for carrying on its respective business and was, at the time of the incurrence
of such indebtedness that will be repaid with the proceeds of the issuance and
sale of the Notes, and will be on the Closing Date (after giving effect to the
application of the proceeds from the issuance of the Notes) able to pay its
respective debts as they mature.



                           (qq) No action has been taken and no law, statute,
rule or regulation or order has been enacted, adopted or issued by any
governmental agency or body which prevents the execution, delivery and
performance of any of the Operative Documents, the issuance of the Notes or the
Subsidiary Guarantees, or suspends the sale of the Notes or the Subsidiary
Guarantees in any jurisdiction referred to in Section 4(e); and no injunction,
restraining order or other order or relief of any nature by a federal or state
court or other tribunal of competent jurisdiction has been issued with respect
to the Company or any of its subsidiaries which would prevent or suspend the
issuance or sale of the Notes or the Subsidiary Guarantees in any jurisdiction
referred to in Section 4(e).

                                                                              16


<PAGE>   18






                           (rr) The Company has complied with all provisions of
Section 517.075, Florida Statutes (Chapter 92-198, Laws of Florida).



         The Company and the Guarantors acknowledge that the Initial Purchasers
and, for purposes of the opinions to be delivered to the Initial Purchasers
pursuant to Section 9 hereof, counsel to the Company and the Guarantors and
counsel to the Initial Purchasers will rely upon the accuracy and truth of the
foregoing representations and hereby consent to such reliance.



                  7. INITIAL PURCHASERS' REPRESENTATIONS AND WARRANTIES. Each of
the Initial Purchasers, severally, and not jointly, represents and warrants to
the Company and the Guarantors, and agrees that:



                           (a) Such Initial Purchaser is a QIB with such
knowledge and experience in financial and business matters as is necessary in
order to evaluate the merits and risks of an investment in the Notes.



                           (b) Such Initial Purchaser (A) is not acquiring the
Notes with a view to any distribution thereof or with any present intention of
offering or selling any of the Notes in a transaction that would violate the Act
or the securities laws of any state of the United States or any other applicable
jurisdiction and (B) will be reoffering and reselling the Notes only to (x) QIBs
in compliance with the exemption from the registration requirements of the Act
provided by Rule 144A and (y) in offshore transactions in compliance with
Regulation S under the Act.



                           (c) No form of general solicitation or general
advertising (within the meaning of Regulation D under the Act) has been or will
be used by such Initial Purchaser or any of its representatives in connection
with the offer and sale of the Notes pursuant hereto, including, but not limited
to, articles, notices or other communications published in any newspaper,
magazine or similar medium or broadcast over television or radio, or any seminar
or meeting whose attendees have been invited by any general solicitation or
general advertising.



                           (d) In connection with Exempt Resales, such Initial
Purchaser will solicit offers to buy the Notes only from, and will offer to sell
the Notes only to, Eligible Purchasers. Each Initial Purchaser further agrees
that it will offer to sell the Notes only to, and will solicit offers to buy the
Notes only from (A) Eligible Purchasers that the Initial Purchaser reasonably
believes are QIBs purchasing for its account or for the account of another QIB
in a transaction meeting the requirements of Rule 144A under the Act, and (B)
Regulation S Purchasers, in each case, that agree that (x) the Notes purchased
by them may be resold, pledged or otherwise transferred within the time period
referred to under Rule 144(k) (taking into account the provisions of Rule 144(d)
under the Act, if applicable) under the Act, as in effect on the date of

                                                                              17


<PAGE>   19






the transfer of such Notes, only (I) to the Company or any of its subsidiaries,
(II) to a person whom the seller reasonably believes is a QIB purchasing for its
own account or for the account of a QIB in a transaction meeting the
requirements of Rule 144A under the Act, (III) in an offshore transaction (as
defined in Rule 902 under the Act) meeting the requirements of Rule 904 of the
Act, (IV) in a transaction meeting the requirements of Rule 144 under the Act,
(V) in accordance with another exemption from the registration requirements of
the Act (and based upon an opinion of counsel acceptable to the Company) or (VI)
pursuant to an effective registration statement and, in each case, in accordance
with the applicable securities laws of any state of the United States or any
other applicable jurisdiction and (y) they will deliver to each person to whom
such Notes or an interest therein is transferred a notice substantially to the
effect of the foregoing.



                           (e) Such Initial Purchaser and its affiliates or any
person acting on its or their behalf have not engaged or will not engage in any
directed selling efforts within the meaning of Regulation S with respect to the
Notes or the Subsidiary Guarantees.



                           (f) The Notes offered and sold by such Initial
Purchaser in reliance on Regulation S have been and will be offered and sold
only in offshore transactions.



                           (g) The sale of the Notes offered and sold by such
Initial Purchaser pursuant hereto in reliance on Regulation S is not part of a
plan or scheme to evade the registration provisions of the Act.



                           (h) It has not offered or sold and will not offer or
sell the Notes in the United States or to, or for the benefit or account of, a
U.S. Person (other than a distributor), in each case, as defined in Rule 902
under the Act (i) as part of its distribution at any time and (ii) otherwise
until 40 days after the later of the commencement of the offering of the Notes
pursuant hereto and the Closing Date, other than in accordance with Regulation S
of the Act or another exemption from the registration requirements of the Act.
Such Initial Purchaser agrees that, during such 40-day distribution compliance
period, it will not cause any advertisement with respect to the Notes (including
any "tombstone" advertisement) to be published in any newspaper or periodical or
posted in any public place and will not issue any circular relating to the
Notes, except such advertisements as are permitted by and include the statements
required by Regulation S.



                           (i) At or prior to confirmation of a sale of Notes by
it to any distributor, dealer or person receiving a selling concession, fee or
other remuneration during the 40-day distribution compliance period referred to
in Rule 903(c)(2) under the Act, it will send to such distributor, dealer or
person receiving a selling concession, fee or other remuneration a confirmation
or notice to substantially the following effect:



                           "The Notes covered hereby have not been registered
under the U.S. Securities Act of 1933, as amended (the "Securities Act"), and
may not be offered and sold within the United States or to,

                                                                              18


<PAGE>   20






or for the account or benefit of, U.S. persons (i) as part of your distribution
at any time or (ii) otherwise until 40 days after the later of the commencement
of the Offering and the Closing Date, except in either case in accordance with
Regulation S under the Securities Act (or Rule 144A or pursuant to another
transaction that is exempt from the registration requirements of the Securities
Act), and in connection with any subsequent sale by you of the Notes covered
hereby in reliance on Regulation S during the period referred to above to any
distributor, dealer or person receiving a selling concession, fee or other
remuneration, you must deliver a notice to substantially the foregoing effect.
Terms used above have the meanings assigned to them in Regulation S."



                           Such Initial Purchaser acknowledges that the Company
and the Guarantors and, for purposes of the opinions to be delivered to each
Initial Purchaser pursuant to Section 9 hereof, counsel to the Company and the
Guarantors and counsel to the Initial Purchasers will rely upon the accuracy and
truth of the foregoing representations and such Initial Purchaser hereby
consents to such reliance.





                  8.       INDEMNIFICATION.



                           (a) The Company and each Guarantor agree, jointly and
severally, to indemnify and hold harmless the Initial Purchasers, their
directors, their officers and each person, if any, who controls such Initial
Purchasers within the meaning of Section 15 of the Act or Section 20 of the
Exchange Act, from and against any and all losses, claims, damages, liabilities
and judgments (including, without limitation, any legal or other expenses
incurred in connection with investigating or defending any matter, including any
action, that could give rise to any such losses, claims, damages, liabilities or
judgments) caused by any untrue statement or alleged untrue statement of a
material fact contained in the Offering Memorandum (or any amendment or
supplement thereto) or any Rule 144A Information provided by the Company or any
Guarantor to any holder or prospective purchaser of Notes pursuant to Section
5(h) or caused by any omission or alleged omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
not misleading, except insofar as such losses, claims, damages, liabilities or
judgments are caused by any such untrue statement or omission or alleged untrue
statement or omission based upon information relating to the Initial Purchasers
furnished in writing to the Company by such Initial Purchasers; provided,
further, that such indemnity with respect to the Offering Memorandum shall not
inure to the benefit of an Initial Purchaser (or any persons controlling such
Initial Purchaser) from whom the person asserting such loss, claim, damage or
liability purchased the Securities which are the subject thereof if such person
did not receive a copy of the Offering Memorandum (or the Offering Memorandum as
amended or supplemented) at or prior to the confirmation of the sale of such
Securities to such person and any such untrue statement or omission or alleged
untrue statement or omission of a material fact contained in such Offering
Memorandum was corrected in the Offering Memorandum.



                           (b) The Initial Purchasers, severally and not jointly
in proportion to the principal amount of Notes which they have respectively
agreed to purchase under Section 2 hereto, agree to indemnify

                                                                              19


<PAGE>   21






and hold harmless the Company and the Guarantors, and their respective directors
and officers and each person, if any, who controls (within the meaning of
Section 15 of the Act or Section 20 of the Exchange Act) the Company or the
Guarantors, to the same extent as the foregoing indemnity from the Company and
the Guarantors to the Initial Purchasers but only with reference to information
relating to the Initial Purchasers furnished in writing to the Company by the
Initial Purchasers expressly for use in the Offering Memorandum.



                           (c) In case any action shall be commenced involving
any person in respect of which indemnity may be sought pursuant to Section 8(a)
or 8(b) (the "INDEMNIFIED PARTY"), the indemnified party shall promptly notify
the person against whom such indemnity may be sought (the "INDEMNIFYING PARTY")
in writing and the indemnifying party shall assume the defense of such action,
including the employment of counsel reasonably satisfactory to the indemnified
party and the payment of all fees and expenses of such counsel, as incurred
(except that in the case of any action in respect of which indemnity may be
sought pursuant to both Sections 8(a) and 8(b), the Initial Purchasers shall not
be required to assume the defense of such action pursuant to this Section 8(c),
but may employ separate counsel and participate in the defense thereof, but the
fees and expenses of such counsel, except as provided below, shall be at the
expense of the Initial Purchasers). Any indemnified party shall have the right
to employ separate counsel in any such action and participate in the defense
thereof, but the fees and expenses of such counsel shall be at the expense of
the indemnified party unless (i) the employment of such counsel shall have been
specifically authorized in writing by the indemnifying party, (ii) the
indemnifying party shall have failed to assume the defense of such action or
employ counsel reasonably satisfactory to the indemnified party or (iii) the
named parties to any such action (including any impleaded parties) include both
the indemnified party and the indemnifying party, and the indemnified party
shall have been advised by such counsel that there may be one or more legal
defenses available to it which are different from or additional to those
available to the indemnifying party and that, as a matter of professional
responsibility, such counsel is unable to represent both the indemnifying and
indemnified (in which case the indemnifying party shall not have the right to
assume the defense of such action on behalf of the indemnified party). In any
such case, the indemnifying party shall not, in connection with any one action
or separate but substantially similar or related actions in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable for the fees and expenses of moe than one separate firm of attorneys (in
addition to any local counsel) for all indemnified parties and all such fees and
expenses shall be reimbursed as they are incurred. Such firm shall be designated
in writing by Donaldson, Lufkin & Jenrette Securities Corporation, in the case
of the parties indemnified pursuant to Section 8(a), and by the Company, in the
case of parties indemnified pursuant to Section 8(b). The indemnifying party
shall indemnify and hold harmless the indemnified party from and against any and
all losses, claims, damages, liabilities and judgments by reason of any
settlement of any action (i) effected with its written consent or (ii) effected
in good faith without its written consent if the settlement is entered into more
than twenty business days after the indemnifying party shall have received a
request from the indemnified party for reimbursement for the fees and expenses
of counsel (in any case where such fees and expenses are at the expense of the
indemnifying party) and, prior to the date of such settlement, the indemnifying
party shall have failed to comply with such reimbursement request unless within
30 days after such reimbursement request is received, the indemnifying party
shall have made a good faith written challenge to the reasonableness of the
amount or nature of the reimbursement requested or the sufficiency of the
documentation supporting the reimbursement requested (which challenge shall set
forth the amount or nature of the requested reimbursement which the indemnifying
party in good faith

                                                                              20


<PAGE>   22






believes to be reasonable or the basis of the good faith claim as to the
insufficiency of any supporting documentation), in which event this clause (ii)
shall apply only if, and to the extent that, such indemnifying party shall not
have reimbursed the indemnified party for the amount which is not being so
challenged. No indemnifying party shall, without the prior written consent of
the indemnified party, effect any settlement or compromise of, or consent to the
entry of judgment wit respect to, any pending or threatened action in respect of
which the indemnified party is or could have been a party and indemnity or
contribution may be or could have been sought hereunder by the indemnified
party, unless such settlement, compromise or judgment (i) includes an
unconditional release of the indemnified party from all liability on claims that
are or could have been the subject matter of such action and (ii) does not
include a statement as to or an admission of fault, culpability or a failure to
act, by or on behalf of the indemnified party.



                           (d) To the extent the indemnification provided for in
this Section 8 is unavailable to an indemnified party or insufficient in respect
of any losses, claims, damages, liabilities or judgments referred to therein,
then each indemnifying party, in lieu of indemnifying such indemnified party,
shall contribute to the amount paid or payable by such indemnified party as a
result of such losses, claims, damages, liabilities and judgments (i) in such
proportion as is appropriate to reflect the relative benefits received by the
Company and the Guarantors, on the one hand, and the Initial Purchasers on the
other hand from the offering of the Notes or (ii) if the allocation provided by
clause 8(d)(i) above is not permitted by applicable law, in such proportion as
is appropriate to reflect not only the relative benefits referred to in clause
8(d)(i) above but also the relative fault of the Company and the Guarantors, on
the one hand, and the Initial Purchasers, on the other hand, in connection with
the statements or omissions which resulted in such losses, claims, damages,
liabilities or judgments, as well as any other relevant equitable
considerations. The relative benefits received by the Company and the
Guarantors, on the one hand and the Initial Purchasers, on the other hand, shall
be deemed to be in the same proportion as the total net proceeds from the
offering of the Notes (after underwriting discounts and commissions, but before
deducting expenses) received by the Company, and the total discounts and
commissions received by the Initial Purchasers bear to the total price to
investors of the Notes, in each case as set forth in the table on the cover page
of the Offering Memorandum. The relative fault of the Company and the
Guarantors, on the one hand, and the Initial Purchasers, on the other hand,
shall be determined by reference to, among other things, whether the untrue or
alleged untrue statement of a material fact or the omission or alleged omission
to state a material fact relates to information supplied by the Company or the
Guarantors, on the one hand, or the Initial Purchasers, on the other hand, and
the parties' relative intent, knowledge, access to information and opportunity
to correct or prevent such statement or omission.



                           The Company and the Guarantors, and the Initial
Purchasers agree that it would not be just and equitable if contribution
pursuant to this Section 8(d) were determined by pro rata allocation (even if
the Initial Purchasers were treated as one entity for such purpose) or by any
other method of allocation which does not take account of the equitable
considerations referred to in the immediately preceding paragraph. The amount
paid or payable by an indemnified party as a result of the losses, claims,
damages, liabilities or judgments referred to in the immediately preceding
paragraph shall be deemed to include, subject to the limitations set forth
above, any legal or other expenses incurred by such indemnified party in
connection with investigating or defending any matter, including any action,
that could have given rise to such losses, claims, damages, liabilities or
judgments. Notwithstanding the provisions of this Section

                                                                              21


<PAGE>   23






8, the Initial Purchasers shall not be required to contribute any amount in
excess of the amount by which the total discounts and commissions received by
such Initial Purchasers exceeds the amount of any damages which the Initial
Purchasers have otherwise been required to pay by reason of such untrue or
alleged untrue statement or omission or alleged omission. No person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation. The Initial Purchasers' obligations to contribute
pursuant to this Section 8(d) are several in proportion to the respective
principal amount of Notes purchased by each of the Initial Purchasers hereunder
and not joint.



                           (e) The remedies provided for in this Section 8 are
not exclusive and shall not limit any rights or remedies which may otherwise be
available to any indemnified party at law or in equity.



                  9.       CONDITIONS OF INITIAL PURCHASERS' OBLIGATIONS. The
obligations of the Initial Purchasers to purchase the Notes under this Agreement
are subject to the satisfaction of each of the following conditions:



                           (a) All the representations and warranties of the
Company and the Guarantors contained in this Agreement shall be true and correct
on the Closing Date with the same force and effect as if made on and as of the
Closing Date.



                           (b) On or after the date hereof, (i) there shall not
have occurred any downgrading, suspension or withdrawal of, nor shall any notice
have been given of any potential or intended downgrading, suspension or
withdrawal of, or of any review (or of any potential or intended review) for a
possible change that does not indicate the direction of the possible change in,
any rating of the Company or any Guarantor or any securities of the Company or
any Guarantor (including, without limitation, the placing of any of the
foregoing ratings on credit watch with negative or developing implications or
under review with an uncertain direction) by any "nationally recognized
statistical rating organization" as such term is defined for purposes of Rule
436(g)(2) under the Act, (ii) there shall not have occurred any change, nor
shall any notice have been given of any potential or intended change, in the
outlook for any rating of the Company or any Guarantor or any securities of the
Company or any Guarantor by any such rating organization and (iii) no such
rating organization shall have given notice that it has assigned (or is
considering assigning) a lower rating to the Notes than that on which the Notes
were marketed.



                           (c) Since the respective dates as of which
information is given in the Offering Memorandum other than as set forth in the
Offering Memorandum (exclusive of any amendments or supplements thereto
subsequent to the date of this Agreement), (i) there shall not have occurred any
change or any development involving a material and adverse prospective change in
the condition, financial or otherwise, or the earnings, business, management or
operations of the Company and its subsidiaries, taken as a whole, (ii) there
shall not have been any change or any development involving a material and
adverse

                                                                              22


<PAGE>   24


prospective change in the capital stock or in the long-term debt of the Company
or any of its subsidiaries and (iii) neither the Company nor any of its
subsidiaries shall have incurred any liability or obligation, direct or
contingent, the effect of which, in any such case described in clause 9(c)(i),
9(c)(ii) or 9(c)(iii), in your judgment, is material and adverse and, in your
judgment, makes it impracticable to market the Notes on the terms and in the
manner contemplated in the Offering Memorandum.



                           (d) You shall have received on the Closing Date a
certificate dated the Closing Date, signed by the President and the Chief
Financial Officer of the Company and each of the Guarantors, confirming the
matters set forth in Sections 6(y), 9(a) and 9(b) and stating that each of the
Company and the Guarantors has complied with all the agreements and satisfied
all of the conditions herein contained and required to be complied with or
satisfied on or prior to the Closing Date.



                           (e) You shall have received on the Closing Date an
opinion (satisfactory to you and counsel for the Initial Purchasers), dated the
Closing Date, of Porter & Hedges, L.L.P., counsel for the Company and the
Guarantors, to the effect set forth in Exhibit B hereto.



                           (f) The Initial Purchasers shall have received an
opinion of Venezuelan counsel to the Company substantially in the form attached
as Schedule D hereto.



                           (g) The Initial Purchasers shall have received on the
Closing Date an opinion, dated the Closing Date, of Akin, Gump, Strauss, Hauer &
Feld, L.L.P., counsel for the Initial Purchasers, in form and substance
reasonably satisfactory to the Initial Purchasers.



                           (h) The Initial Purchasers shall have received, at
the time this Agreement is executed and at the Closing Date, a letter dated the
date hereof or the Closing Date, as the case may be, in form and substance
satisfactory to the Initial Purchasers from KPMG Peat Marwick LLP, independent
public accountants, containing the information and statements of the type
ordinarily included in accountants' "comfort letters" to the Initial Purchasers
with respect to the financial statements and certain financial information
contained in the Offering Memorandum.



                           (i) The Notes shall have been approved by the NASD
for trading and duly listed in PORTAL.



                           (j) The Initial Purchasers shall have received a
counterpart, conformed as executed, of the Indenture which shall have been
entered into by the Company, the Guarantors and the Trustee.



                                                                              23


<PAGE>   25



                           (k) The Company and the Guarantors shall have
executed the Registration Rights Agreement and the Initial Purchasers shall have
received an original copy thereof, duly executed by the Company and the
Guarantors.



                           (l) Neither the Company nor the Guarantors shall have
failed at or prior to the Closing Date to perform or comply with any of the
agreements herein contained and required to be performed or complied with by the
Company or the Guarantors, as the case may be, at or prior to the Closing Date.



                           (m) The Company shall have received any approvals or
consents from the lenders under the Bank Credit Facility (as defined in the
Offering Memorandum) necessary in order to consummate the issuance of Notes
contemplated hereby.



                           (n) The Company shall have received the requisite
consent from the holders of the Series A Notes (as defined in the Offering
Memorandum) to issue the Second Supplemental Indenture (the "Series A
Supplemental Indenture") to the Indenture, dated June 27, 1997, governing the
Series A Notes, and shall have entered into the Series A Supplemental Indenture
with the trustee under such indenture.



               10. EFFECTIVENESS OF AGREEMENT AND TERMINATION. This Agreement
shall become effective upon the execution and delivery of this Agreement by the
parties hereto.



               This Agreement may be terminated at any time on or prior to the
Closing Date by the Initial Purchasers by written notice to the Company if any
of the following has occurred: (i) any outbreak or escalation of hostilities or
other national or international calamity or crisis or change in economic
conditions or in the financial markets of the United States or elsewhere that,
in the Initial Purchasers' judgment, is material and adverse and, in the Initial
Purchasers' judgment, makes it impracticable to market the Notes on the terms
and in the manner contemplated in the Offering Memorandum, (ii) the suspension
or material limitation of trading in securities or other instruments on the New
York Stock Exchange, the American Stock Exchange, the Chicago Board of Options
Exchange, the Chicago Mercantile Exchange, the Chicago Board of Trade or the
Nasdaq National Market or limitation on prices for securities or other
instruments on any such exchange or the Nasdaq National Market, (iii) the
suspension of trading of any securities of the Company or any Guarantor on any
exchange or in the over-the-counter market, (iv) the enactment, publication,
decree or other promulgation of any federal or state statute, regulation, rule
or order of any court or other governmental authority which in your opinion
materially and adversely affects, or will materially and adversely affect, the
business, prospects, financial condition or results of operations of the Company
and its subsidiaries, taken as a whole, (v) the declaration of a banking
moratorium by either federal or New York State authorities or (vi) the taking of
any action by any federal, state or local government or agency in respect of its
monetary or fiscal affairs which in your opinion has a material adverse effect
on the financial markets in the United States and would, in your opinion, make
it impracticable or inadvisable to market the Notes.



                                                                              24


<PAGE>   26






               If on the Closing Date any one or more of the Initial Purchasers
shall fail or refuse to purchase the Notes which it or they have agreed to
purchase hereunder on such date and the aggregate principal amount of the Notes
which such defaulting Initial Purchaser or Initial Purchasers, as the case may
be, agreed but failed or refused to purchase is not more than one-tenth of the
aggregate principal amount of the Notes to be purchased on such date by all
Initial Purchasers, each non-defaulting Initial Purchaser shall be obligated
severally, in the proportion which the principal amount of the Notes set forth
opposite its name in Schedule B bears to the aggregate principal amount of the
Notes which all the non-defaulting Initial Purchasers, as the case may be, have
agreed to purchase, or in such other proportion as you may specify, to purchase
the Notes which such defaulting Initial Purchaser or Initial Purchasers, as the
case may be, agreed but failed or refused to purchase on such date; provided
that in no event shall the aggregate principal amount of the Notes which any
Initial Purchaser has agreed to purchase pursuant to Section 2 hereof be
increased pursuant to this Section 10 by an amount in excess of one-ninth of
such principal amount of the Notes without the written consent of such Initial
Purchaser. If on the Closing Date any Initial Purchaser or Initial Purchasers
shall fail or refuse to purchase the Notes and the aggregate principal amount of
the Notes with respect to which such default occurs is more than one-tenth of
the aggregate principal amount of the Notes to be purchased by all Initial
Purchasers and arrangements satisfactory to the Initial Purchasers and the
Company for purchase of such the Notes are not made within 48 hours after such
default, this Agreement will terminate without liability on the part of any
non-defaulting Initial Purchaser and the Company. In any such case which does
not result in termination of this Agreement, either you or the Company shall
have the right to postpone the Closig Date, but in no event for longer than
seven days, in order that the required changes, if any, in the Offering
Memorandum or any other documents or arrangements may be effected. Any action
taken under this paragraph shall not relieve any defaulting Initial Purchaser
from liability in respect of any default of any such Initial Purchaser under
this Agreement.



               11. MISCELLANEOUS. Notices given pursuant to any provision of
this Agreement shall be addressed as follows: (i) if to the Company or any
Guarantor, to 10370 Richmond Avenue, Suite 600, Houston, Texas 77042 (713)
435-6100, Attention: Secretary and (ii) if to the Initial Purchasers, Donaldson,
Lufkin & Jenrette Securities Corporation, 277 Park Avenue, New York, New York
10172, Attention: Syndicate Department, or in any case to such other address as
the person to be notified may have requested in writing.



               The respective indemnities, contribution agreements,
representations, warranties and other statements of the Company, the Guarantors
and the Initial Purchasers set forth in or made pursuant to this Agreement shall
remain operative and in full force and effect, and will survive delivery of and
payment for the Notes, regardless of (i) any investigation, or statement as to
the results thereof, made by or on behalf of the Initial Purchasers, the
officers or directors of the Initial Purchasers, any person controlling the
Initial Purchasers, the Company, any Guarantor, the officers or directors of the
Company or any Guarantor, or any person controlling the Company or any
Guarantor, (ii) acceptance of the Notes and payment for them hereunder and (iii)
termination of this Agreement.



               If for any reason the Notes are not tendered for delivery by or
on behalf of the Company as provided herein (other than as a result of any
termination of this Agreement pursuant to Section 10), the

                                                                              25


<PAGE>   27






Company and each Guarantor, jointly and severally, agree to reimburse the
Initial Purchaser for all out-of-pocket expenses (including the fees and
disbursements of counsel) incurred by them. Notwithstanding any termination of
this Agreement, the Company shall be liable for all expenses which it has agreed
to pay pursuant to Section 5(i) hereof. The Company and each Guarantor also
agree, jointly and severally, to reimburse the Initial Purchasers and its
officers, directors and each person, if any, who controls such Initial
Purchasers within the meaning of Section 15 of the Act or Section 20 of the
Exchange Act for any and all fees and expenses (including without limitation the
fees and expenses of counsel) incurred by them in connection with enforcing
their rights under this Agreement (including without limitation its rights under
Section 8).



               Except as otherwise provided, this Agreement has been and is made
solely for the benefit of and shall be binding upon the Company, the Guarantors,
the Initial Purchasers, the Initial Purchasers' directors and officers, any
controlling persons referred to herein, the directors of the Company and the
Guarantors and their respective successors and assigns, all as and to the extent
provided in this Agreement, and no other person shall acquire or have any right
under or by virtue of this Agreement. The term "successors and assigns" shall
not include a purchaser of any of the Notes from the Initial Purchaser merely
because of such purchase.



               This Agreement shall be governed and construed in accordance with
the laws of the State of New York.



               This Agreement may be signed in various counterparts which
together shall constitute one and the same instrument.





             [The remainder of this page intentionally left blank.]



                                                                              26


<PAGE>   28






         Please confirm that the foregoing correctly sets forth the agreement
among the Company, the Guarantors and the Initial Purchasers.





                         Very truly yours,



                         GREY WOLF, INC.



                         By: /s/DAVID W. WEHLMANN
                            ----------------------------------------------------
                         Name: David W. Wehlmann

                         Title:Senior Vice President and Chief Financial Officer



                         GREY WOLF DRILLING COMPANY



                         By:/s/ DAVID W. WEHLMANN
                            ----------------------------------------------------
                         Name: David W. Wehlmann

                         Title:Senior Vice President and Chief Financial Officer



                         DI ENERGY, INC.



                         By: /s/ DAVID W. WEHLMANN
                            ----------------------------------------------------
                         Name:  David W. Wehlmann

                         Title:Senior Vice President and Chief Financial Officer













<PAGE>   29






                         GREY WOLF INTERNATIONAL, INC.



                         By:/s/ DAVID W. WEHLMANN
                            ----------------------------------------------------
                         Name: David W. Wehlmann

                         Title:Senior Vice President and Chief Financial Officer



                         MURCO DRILLING CORPORATION



                         By:/s/ DAVID W. WEHLMANN
                            ----------------------------------------------------
                         Name: David W. Wehlmann

                         Title:  Secretary











<PAGE>   30






DONALDSON, LUFKIN & JENRETTE

     SECURITIES CORPORATION

LEHMAN BROTHERS INC.

PRUDENTIAL SECURITIES  INCORPORATED







By:      DONALDSON, LUFKIN & JENRETTE

              SECURITIES CORPORATION







By:      /s/ CRAIG KLAASMEYER
         --------------------------------------
         Name:    Craig Klaasmeyer

         Title:   Vice President








<PAGE>   31











                                       A-1




                                   SCHEDULE A
                               INITIAL GUARANTORS

<TABLE>
<CAPTION>


            Name of Guarantor                              State of Incorporation
- ------------------------------------------      --------------------------------------------
<S>                                             <C>
Grey Wolf Drilling Company                                         Texas
Murco Drilling Corporation (a                                     Delaware
wholly-owned subsidiary of Grey
Wolf Drilling Company)
Grey Wolf International, Inc.                                      Texas
DI Energy, Inc.                                                    Texas
</TABLE>











<PAGE>   32








                                       B-1




                                   SCHEDULE B

                               INITIAL PURCHASERS

<TABLE>
<CAPTION>


                                                                                 PRINCIPAL AMOUNT
        INITIAL PURCHASER                                                            OF NOTES
        -----------------                                                        ----------------
<S>                                                                              <C>
Donaldson, Lufkin & Jenrette
     Securities Corporation..................................................   $  37,500,000
Lehman Brothers Inc..........................................................      18,750,000
Prudential Securities  Incorporated..........................................      18,750,000
                                                                                -------------
     TOTAL...................................................................   $  75,000,000
                                                                                =============
</TABLE>











<PAGE>   33











                                       C-1




                                   SCHEDULE C

                                  SUBSIDIARIES











<PAGE>   34











                                   SCHEDULE D

                          OPINION OF VENEZUELAN COUNSEL



                                       C-1







<PAGE>   35







                                       C-2


                                    EXHIBIT A

                      FORM OF REGISTRATION RIGHTS AGREEMENT








<PAGE>   1
                                                                     EXHIBIT 4.2








                         REGISTRATION RIGHTS AGREEMENT


                            Dated as of May 8, 1998
                                  by and among

                                GREY WOLF, INC.

                                 THE GUARANTORS

                                      and

                          DONALDSON, LUFKIN & JENRETTE
                             SECURITIES CORPORATION
                              LEHMAN BROTHERS INC.
                       PRUDENTIAL SECURITIES INCORPORATED
<PAGE>   2
                         REGISTRATION RIGHTS AGREEMENT

     This REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT") is made and entered
into as of May 8, 1998, by and among Grey Wolf, Inc., a Texas corporation (the
"COMPANY"), each of the subsidiaries listed on Schedule A attached hereto (each
a "GUARANTOR" and, collectively, the "GUARANTORS"), and Donaldson, Lufkin &
Jenrette Securities Corporation, Lehman Brothers Inc. and Prudential Securities
Incorporated (each an "INITIAL PURCHASER" and, collectively, the "INITIAL
PURCHASERS"), each of whom has agreed to purchase the Company's 8 7/8% Senior
Notes due 2007, Series B (the "NOTES") pursuant to the Purchase Agreement (as
defined below).

          This Agreement is made pursuant to the Purchase Agreement, dated May
5, 1998 (the "PURCHASE AGREEMENT"), by and among the Company, the Guarantors
and the Initial Purchasers.  In order to induce the Initial Purchasers to
purchase the Notes, the Company has agreed to provide the registration rights
set forth in this Agreement, on the terms and subject to the conditions herein
set forth.  The execution and delivery of this Agreement is the condition to
the obligations of the Initial Purchasers set forth in Section 9(k) of the
Purchase Agreement.  Capitalized terms used herein and not otherwise defined
shall have the meaning assigned to them in the Indenture, dated May 8, 1998,
between the Company and Chase Bank of Texas, N.A., as Trustee, relating to the
Notes and the Exchange Notes (the "INDENTURE").

          The parties hereby agree as follows:

SECTION 1.       DEFINITIONS

          As used in this Agreement, the following capitalized terms shall have
the following meanings:

          ACT:  The Securities Act of 1933, as amended.

          AFFILIATE:       As defined in Rule 144 of the Act.

          BROKER-DEALER:  Any broker or dealer registered under the Exchange
Act.

          BUSINESS DAY:     Any day other than a Saturday, Sunday or day that
commercial banks in New York are required or permitted to be closed.

          CERTIFICATED SECURITIES:  Definitive Notes, as defined in the
Indenture.

          CLOSING DATE:  The date hereof.

          COMMISSION:  The Securities and Exchange Commission.

          CONSUMMATE:  An Exchange Offer shall be deemed "Consummated" for
purposes of this Agreement upon the occurrence of (a) the filing and
effectiveness under the Act of the Exchange Offer Registration Statement
relating to the Exchange Notes to be issued in the Exchange Offer, (b) the
<PAGE>   3
maintenance of such Exchange Offer Registration Statement continuously
effective and the keeping of the Exchange Offer open for a period not less than
the period required pursuant to Section 3(b) hereof and (c) the delivery by the
Company to the Registrar under the Indenture (as such term is defined therein)
of Exchange Notes in the same aggregate principal amount as the aggregate
principal amount of Notes tendered by Holders thereof pursuant to the Exchange
Offer.

          CONSUMMATION DEADLINE:  As defined in Section 3(b) hereof.

          EFFECTIVENESS DEADLINE:  As defined in Section 3(a) and 4(a) hereof.

          EXCHANGE ACT:  The Securities Exchange Act of 1934, as amended.

          EXCHANGE NOTES:  The Company's 8 7/8% Exchange Notes due 2007, Series
B to be issued pursuant to the Indenture in the Exchange Offer.

          EXCHANGE OFFER:  The exchange and issuance by the Company of a
principal amount of Exchange Notes (which shall be registered pursuant to the
Exchange Offer Registration Statement) equal to the outstanding principal
amount of Notes that are tendered by such Holders in connection with such
exchange and issuance.

          EXCHANGE OFFER REGISTRATION STATEMENT:  The Registration Statement
relating to the Exchange Offer, including the related Prospectus.

          EXEMPT RESALES:  The transactions in which the Initial Purchasers
propose to sell the Notes to certain "qualified institutional buyers," as such
term is defined in Rule 144A under the Act and pursuant to Regulation S under
the Act.

          FILING DEADLINE:  As defined in Sections 3(a) and 4(a) hereof.

          HOLDERS:  As defined in Section 2 hereof.

          PROSPECTUS:  The prospectus included in a Registration Statement at
the time such Registration Statement is declared effective, as amended or
supplemented by any prospectus supplement and by all other amendments thereto,
including post-effective amendments, and all material incorporated by reference
into such Prospectus.

          RECOMMENCEMENT DATE: As defined in Section 6(d) hereof.

          REGISTRATION DEFAULT:  As defined in Section 5 hereof.

          REGISTRATION STATEMENT:  Any registration statement of the Company
and the Guarantors relating to (a) an offering of Exchange Notes pursuant to an
Exchange Offer or (b) the registration for resale of Transfer Restricted
Securities pursuant to the Shelf Registration Statement, in each case, (i) that
is filed pursuant to the provisions of this Agreement and (ii) including the
Prospectus included therein, all amendments and supplements thereto (including
post-effective amendments) and all exhibits and material incorporated by
reference therein.




                                      2
<PAGE>   4
          REGULATION S: Regulation S promulgated under the Act.

          RULE 144: Rule 144 promulgated under the Act.

          SHELF REGISTRATION STATEMENT:  As defined in Section 4 hereof.

          SUSPENSION NOTICE:  As defined in Section 6(d) hereof.

          TIA: The Trust Indenture Act of 1939 (15 U.S.C. Section 77aaa-77bbbb)
as in effect on the date of the Indenture.

          TRANSFER RESTRICTED SECURITIES: Each Note, until the earliest to
occur of (a) the date on which such Note is exchanged in the Exchange Offer for
a Exchange Note which is entitled to be resold to the public by the Holder
thereof without complying with the prospectus delivery requirements of the Act,
(b) the date on which such Note has been disposed of in accordance with a Shelf
Registration Statement (and the purchasers thereof have been issued Exchange
Notes), or (c) the date on which such Note is distributed to the public
pursuant to Rule 144 under the Act (and purchasers thereof have been issued
Exchange Notes), and each Exchange Note until the date on which such Exchange
Note is disposed of by a Broker-Dealer pursuant to the "Plan of Distribution"
contemplated by the Exchange Offer Registration Statement (including the
delivery of the Prospectus contained therein).

SECTION 2.       HOLDERS

          A Person is deemed to be a holder of Transfer Restricted Securities
(each, a "HOLDER") whenever such Person owns Transfer Restricted Securities.

SECTION 3.       REGISTERED EXCHANGE OFFER

          (a)  Unless the Exchange Offer shall not be permitted by applicable
federal law or interpretations of the staff of the Commission (after the
procedures set forth in Section 6(a)(i) below have been complied with), the
Company and the Guarantors shall (i) cause the Exchange Offer Registration
Statement to be filed with the Commission as soon as practicable after the
Closing Date, but in no event later than 60 days after the Closing Date (such
60th day being the "FILING DEADLINE"), (ii) use its reasonable best efforts to
cause such Exchange Offer Registration Statement to become effective at the
earliest possible time, but in no event later than 120 days after the Closing
Date (such 120th day being the "EFFECTIVENESS DEADLINE"), (iii) in connection
with the foregoing, (A) file all pre-effective amendments to such Exchange
Offer Registration Statement as may be necessary in order to cause it to become
effective, (B) file, if applicable, a post-effective amendment to such Exchange
Offer Registration Statement pursuant to Rule 430A under the Act and (C) cause
all necessary filings, if any, in connection with the registration and
qualification of the Exchange Notes to be made under the Blue Sky laws of such
jurisdictions as are necessary to permit Consummation of the Exchange Offer,
and (iv) upon the effectiveness of such Exchange Offer Registration Statement,
commence and Consummate the Exchange Offer.  The Exchange Offer shall be on the
appropriate form permitting (i) registration of the Exchange Notes to be
offered in exchange for the Notes that are Transfer Restricted Securities and
(ii) resales of Exchange Notes by Broker- Dealers that tendered into the
Exchange Offer Notes that such Broker-Dealer acquired for its own account as a
result of market making activities or other trading




                                      3
<PAGE>   5
activities (other than Notes acquired directly from the Company or any of its
Affiliates) as contemplated by Section 3(c) below.

          (b)  The Company and the Guarantors shall use their respective
reasonable best efforts to cause the Exchange Offer Registration Statement to
be effective continuously, and shall keep the Exchange Offer open for a period
of not less than the minimum period required under applicable federal and state
securities laws to Consummate the Exchange Offer; provided, however, that in no
event shall such period be less than 20 Business Days.  The Company and the
Guarantors shall cause the Exchange Offer to comply with all applicable federal
and state securities laws.  No securities other than the Exchange Notes shall
be included in the Exchange Offer Registration Statement.  The Company and the
Guarantors shall use their respective reasonable best efforts to cause the
Exchange Offer to be Consummated on the earliest practicable date after the
Exchange Offer Registration Statement has become effective, but in no event
later than 30 days thereafter (such 30th day being the "CONSUMMATION
DEADLINE").

          (c)  The Company shall include a "Plan of Distribution" section in
the Prospectus contained in the Exchange Offer Registration Statement and
indicate therein that any Broker-Dealer who holds Transfer Restricted
Securities that were acquired for the account of such Broker-Dealer as a result
of market-making activities or other trading activities (other than Notes
acquired directly from the Company or any Affiliate of the Company), may
exchange such Transfer Restricted Securities pursuant to the Exchange Offer.
Such "Plan of Distribution" section shall also contain all other information
with respect to such sales by such Broker-Dealers that the Commission may
require in order to permit such sales pursuant thereto, but such "Plan of
Distribution" shall not name any such Broker-Dealer or disclose the amount of
Transfer Restricted Securities held by any such Broker-Dealer, except to the
extent required by the Commission as a result of a change in policy, rules or
regulations after the date of this Agreement.  See the Shearman & Sterling no-
action letter (available July 2, 1993).

          Because such Broker-Dealer may be deemed to be an "underwriter"
within the meaning of the Act and must, therefore, deliver a prospectus meeting
the requirements of the Act in connection with its initial sale of any Exchange
Notes received by such Broker-Dealer in the Exchange Offer, the Company and
Guarantors shall permit the use of the Prospectus contained in the Exchange
Offer Registration Statement by such Broker-Dealer to satisfy such prospectus
delivery requirement.  To the extent necessary to ensure that the prospectus
contained in the Exchange Offer Registration Statement is available for sales
of Exchange Notes by Broker-Dealers, the Company and the Guarantors agree to
use their respective reasonable best efforts to keep the Exchange Offer
Registration Statement continuously effective, supplemented, amended and
current as required by, and subject to, the provisions of Section 6(a) and (c)
hereof and in conformity with the requirements of this Agreement, the Act and
the policies, rules and regulations of the Commission as announced from time to
time, for a period of one year from the Consummation Deadline or such shorter
period as will terminate when all Transfer Restricted Securities covered by
such Registration Statement have been sold pursuant thereto.  The Company and
the Guarantors shall provide sufficient copies of the latest version of such
Prospectus to such Broker-Dealers, promptly upon request, and in no event later
than three Business Days after such request, at any time during such period.




                                      4
<PAGE>   6
SECTION 4.       SHELF REGISTRATION

          (a)  Shelf Registration.  If (i) the Exchange Offer is not permitted
by applicable law or interpretations of the staff of the Commission (after the
Company and the Guarantors have complied with the procedures set forth in
Section 6(a)(i) below) or (ii) if any Holder of Transfer Restricted Securities
shall notify the Company within 30 days following the Consummation Deadline
that (A) such Holder was prohibited by law or Commission policy from
participating in the Exchange Offer and stating the reason for the application
of such prohibition to the Holder or (B) such Holder may not resell the
Exchange Notes acquired by it in the Exchange Offer to the public without
delivering a prospectus and the Prospectus contained in the Exchange Offer
Registration Statement is legally unavailable for such resales by such Holder
or (C) such Holder is a Broker-Dealer and holds Notes acquired directly from
the Company or any of its Affiliates, then the Company and the Guarantors
shall:

     (x) cause to be filed as promptly as practicable but no later than 45 days
after the earlier of (i) the date on which the Company determines that the
Exchange Offer Registration Statement cannot be filed as a result of clause
(a)(i) above and (ii) the date on which the Company receives the notice
specified in clause (a)(ii) above, (such earlier date, the "FILING DEADLINE"),
a shelf registration statement pursuant to Rule 415 under the Act (which may be
an amendment to the Exchange Offer Registration Statement (the "SHELF
REGISTRATION STATEMENT")), relating to all Transfer Restricted Securities, and

     (y) shall use their respective reasonable best efforts to cause such Shelf
Registration Statement to become effective on or prior to 60 days after the
Filing Deadline for the Shelf Registration Statement (such 60th day, the
"EFFECTIVENESS DEADLINE").

          If, after the Company has filed an Exchange Offer Registration
Statement that satisfies the requirements of Section 3(a) above, the Company is
required to file and make effective a Shelf Registration Statement solely
because the Exchange Offer is not permitted under applicable federal law (i.e.,
clause (a)(i) above), then the filing of the Exchange Offer Registration
Statement shall be deemed to satisfy the requirements of clause (x) above;
provided that, in such event, the Company shall remain obligated to meet the
Effectiveness Deadline set forth in clause (y).

          To the extent necessary to ensure that the Shelf Registration
Statement is available for sales of Transfer Restricted Securities by the
Holders thereof entitled to the benefit of this Section 4(a) and the other
securities required to be registered therein pursuant to Section 6(b)(ii)
hereof, the Company and the Guarantors shall use their respective reasonable
best efforts to keep any Shelf Registration Statement required by this Section
4(a) continuously effective, supplemented, amended and current as required by,
and subject to, the provisions of Sections 6(b) and (c) hereof and in
conformity with the requirements of this Agreement, the Act and the policies,
rules and regulations of the Commission as announced from time to time, for a
period ending the earlier of (i) the time when the Notes covered thereby can be
sold pursuant to Rule 144 under the Act without any limitations under clause
(c), (e), (f) and (h) thereof and (ii) at least two years (as extended pursuant
to Section 6(c)(i)) following the Closing Date, or such shorter period as will
terminate when all Transfer Restricted Securities covered by such Shelf
Registration Statement have been sold pursuant thereto.

          (b)  Provision by Holders of Certain Information in Connection with
the Shelf Registration Statement.  No Holder of Transfer Restricted Securities
may include any of its Transfer Restricted Securities in any Shelf Registration
Statement pursuant to this Agreement unless and until such Holder furnishes to
the Company in writing, the information specified in Item 507 or 508 of
Regulation S-K, as applicable, of the Act for use in connection with any Shelf
Registration Statement or Prospectus or preliminary Prospectus




                                      5
<PAGE>   7
included therein, such information to be provided within 10 days after a
request therefor in the case of a Shelf Registration Statement to be filed as a
consequence of Section 4(a)(i) or, in the case of a Shelf Registration
Statement filed as a consequence of a Holder's notification under Section
4(a)(ii), within 10 days after such notice.  No Holder of Transfer Restricted
Securities shall be entitled to special interest (as defined herein) pursuant
to Section 5 hereof unless and until such Holder shall have provided all such
information.  Each selling Holder agrees to promptly furnish in writing
additional information required to be disclosed in order to make the
information previously furnished to the Company by such Holder not materially
misleading.

SECTION 5.       SPECIAL INTEREST

          If (i) any Registration Statement required by this Agreement is not
filed with the Commission on or prior to the applicable Filing Deadline, (ii)
any such Registration Statement has not been declared effective by the
Commission on or prior to the applicable Effectiveness Deadline, (iii) the
Exchange Offer has not been Consummated on or prior to the Consummation
Deadline or (iv) any Registration Statement required by this Agreement is filed
and declared effective but shall thereafter cease to be effective or fail to be
usable for its intended purpose (for reasons other than those permitted by
Section 6(c) or 6(d)) without being succeeded by a post-effective amendment to
such Registration Statement that cures such failure and that is itself declared
effective (each such event referred to in clauses (i) through (iv), a
"REGISTRATION DEFAULT"), then the Company and the Guarantors hereby jointly and
severally agree to pay to each Holder of Transfer Restricted Securities
affected thereby additional interest ("SPECIAL INTEREST") in an amount equal to
$.05 per week per $1,000 in principal amount of Transfer Restricted Securities
held by such Holder for each week or portion thereof that the Registration
Default continues for the first 90-day period immediately following the
occurrence of such Registration Default.  The amount of the special interest
shall increase by an additional $.05 per week per $1,000 in principal amount of
Transfer Restricted Securities with respect to each subsequent 90-day period
until all Registration Defaults have been cured, up to a maximum amount of
special interest of $.25 per week per $1,000 in principal amount of Transfer
Restricted Securities; provided that the Company and the Guarantors shall in no
event be required to pay special interest for more than one Registration
Default at any given time.  Notwithstanding anything to the contrary set forth
herein, (1) upon filing of the Exchange Offer Registration Statement (and/or,
if applicable, the Shelf Registration Statement), in the case of (i) above, (2)
upon the effectiveness of the Exchange Offer Registration Statement (and/or, if
applicable, the Shelf Registration Statement), in the case of (ii) above, (3)
upon Consummation of the Exchange Offer, in the case of (iii) above, or (4)
upon the filing of a post-effective amendment to the Registration Statement or
an additional Registration Statement that causes the Exchange Offer
Registration Statement (and/or, if applicable, the Shelf Registration
Statement) to again be declared effective or made usable in the case of (iv)
above, the special interest payable with respect to the Transfer Restricted
Securities as a result of such clause (i), (ii), (iii) or (iv), as applicable,
shall cease.  The right of each Holder to receive Special Interest shall be the
exclusive remedy and liquidated damages for any and all Registration Defaults.

          All accrued special interest shall be paid to the Holders entitled
thereto, in the manner provided for the payment of interest in the Indenture,
on each Interest Payment Date, as more fully set forth in the Indenture and the
Notes.  Notwithstanding the fact that any securities for which special interest
are due cease to be Transfer Restricted Securities, all obligations of the
Company and the Guarantors to pay special interest with respect to securities
shall survive until such time as such obligations with respect to such
securities shall have been satisfied in full.




                                      6
<PAGE>   8

SECTION 6.       REGISTRATION PROCEDURES

          (a)  Exchange Offer Registration Statement.  In connection with the
Exchange Offer, the Company and the Guarantors shall (x) comply with all
applicable provisions of Section 6(c) below, (y) use their respective
reasonable best efforts to effect such exchange and to permit the resale of
Exchange Notes by Broker-Dealers that tendered in the Exchange Offer Notes that
such Broker-Dealer acquired for its own account as a result of its market
making activities or other trading activities (other than Notes acquired
directly from the Company or any of its Affiliates) being sold in accordance
with the intended method or methods of distribution thereof, and (z) comply
with all of the following provisions:

               (i)  If, following the date hereof there has been announced a
     change in Commission policy with respect to exchange offers such as the
     Exchange Offer, that in the reasonable opinion of counsel to the Company
     raises a substantial question as to whether the Exchange Offer is
     permitted by applicable federal law, the Company and the Guarantors hereby
     agree to seek a no-action letter or other favorable decision from the
     Commission allowing the Company and the Guarantors to Consummate an
     Exchange Offer for such Transfer Restricted Securities.  The Company and
     the Guarantors hereby agree to pursue the issuance of such a decision to
     the Commission staff level.  In connection with the foregoing, the Company
     and the Guarantors hereby agree to take all such other actions as may be
     requested by the Commission or otherwise required in connection with the
     issuance of such decision, including without limitation (A) participating
     in telephonic conferences with the Commission, (B) delivering to the
     Commission staff an analysis prepared by counsel to the Company setting
     forth the legal bases, if any, upon which such counsel has concluded that
     such an Exchange Offer should be permitted and (C) diligently pursuing a
     resolution (which need not be favorable) by the Commission staff.

               (ii)  As a condition to its participation in the Exchange Offer,
     each Holder of Transfer Restricted Securities (including, without
     limitation, any Holder who is a Broker-Dealer) shall furnish, upon the
     request of the Company, prior to the Consummation of the Exchange Offer, a
     written representation to the Company and the Guarantors (which may be
     contained in the letter of transmittal contemplated by the Exchange Offer
     Registration Statement) to the effect that (A) it is not an Affiliate of
     the Company, (B) it is not engaged in, and does not intend to engage in,
     and has no arrangement or understanding with any person to participate in,
     a distribution of the Exchange Notes to be issued in the Exchange Offer
     and (C) it is acquiring the Exchange Notes in its ordinary course of
     business.  As a condition to its participation in the Exchange Offer, each
     Holder using the Exchange Offer to participate in a distribution of the
     Exchange Notes shall acknowledge and agree that, if the resales are of
     Exchange Notes obtained by such Holder in exchange for Notes acquired
     directly from the Company or an Affiliate thereof, it (1) could not, under
     Commission policy as in effect on the date of this Agreement, rely on the
     position of the Commission enunciated in Morgan Stanley and Co., Inc.
     (available June 5, 1991) and Exxon Capital Holdings Corporation (available
     May 13, 1988), as interpreted in the Commission's letter to Shearman &
     Sterling dated July 2, 1993, and similar no-action letters (including, if
     applicable, any no-action letter obtained pursuant to clause (i) above),
     and (2) must comply with the registration and prospectus delivery
     requirements of the Act in connection with a secondary resale transaction
     and that such a secondary resale transaction must be covered by an
     effective registration statement containing the selling security holder
     information required by Item 507 or 508, as applicable, of Regulation S-K.




                                      7
<PAGE>   9
               (iii)  Prior to effectiveness of the Exchange Offer Registration
     Statement, the Company and the Guarantors shall provide a supplemental
     letter to the Commission (A) stating that the Company and the Guarantors
     are registering the Exchange Offer in reliance on the position of the
     Commission enunciated in Exxon Capital Holdings Corporation (available May
     13, 1988), Morgan Stanley and Co., Inc. (available June 5, 1991) as
     interpreted in the Commission's letter to Shearman & Sterling dated July
     2, 1993, and, if applicable, any no-action letter obtained pursuant to
     clause (i) above, (B) including a representation that neither the Company
     nor any Guarantor has entered into any arrangement or understanding with
     any Person to distribute the Exchange Notes to be received in the Exchange
     Offer and that (if true) to the best of the Company's and each Guarantor's
     information and belief, each Holder participating in the Exchange Offer is
     acquiring the Exchange Notes in its ordinary course of business and has no
     arrangement or understanding with any Person to participate in the
     distribution of the Exchange Notes received in the Exchange Offer and (C)
     any other undertaking or representation required by the Commission as set
     forth in any no-action letter obtained pursuant to clause (i) above, if
     applicable.

          (b)  Shelf Registration Statement. In connection with the Shelf
Registration Statement, the Company and the Guarantors shall (i) comply with
all the provisions of Section 6(c) below and use their respective reasonable
best efforts to effect such registration to permit the sale of the Transfer
Restricted Securities being sold in accordance with the intended method or
methods of distribution thereof (as indicated in the information furnished to
the Company pursuant to Section 4(b) hereof), and pursuant thereto the Company
and the Guarantors will prepare and file with the Commission a Registration
Statement relating to the registration on any appropriate form under the Act
(which may include an amendment to the Exchange Offer Registration Statement),
which form shall be available for the sale of the Transfer Restricted
Securities in accordance with the intended method or methods of distribution
thereof within the time periods and otherwise in accordance with the provisions
hereof and

               (ii) issue, upon the request of any Holder covered by any Shelf
Registration Statement contemplated by this Agreement, Exchange Notes having an
aggregate principal amount equal to the aggregate principal amount of Notes
sold pursuant to the Shelf Registration Statement and surrendered to the
Company for cancellation; and the Company shall register Exchange Notes on the
Shelf Registration Statement for this purpose.

          (c)  General Provisions.  In connection with any Registration
Statement and any related Prospectus required by this Agreement, the Company
and the Guarantors shall:

               (i)  use their respective reasonable best efforts to keep such
     Registration Statement continuously effective and provide all requisite
     financial statements for the period specified in Section 3 or 4 of this
     Agreement, as applicable.  Upon the occurrence of any event that would
     cause any such Registration Statement or the Prospectus contained therein
     (A) to contain an untrue statement of material fact or omit to state any
     material fact necessary to make the statements therein not misleading or
     (B) not to be effective and usable for resale of Transfer Restricted
     Securities during the period required by this Agreement, the Company and
     the Guarantors shall file promptly (unless excused by Section 6(d) with
     respect to an event or circumstance contemplated by Section 6(c)(iii)(E))
     an appropriate amendment or Prospectus Supplement to such Registration
     Statement curing such defect, and, if Commission review is required, use
     their respective reasonable best efforts to cause such amendment to be
     declared effective as soon as practicable.




                                      8
<PAGE>   10
               (ii)  prepare and file with the Commission such amendments and
     post-effective amendments to the applicable Registration Statement as may
     be necessary to keep such Registration Statement effective for the
     applicable period set forth in Section 3 or 4 hereof, as the case may be;
     cause the Prospectus to be supplemented by any required Prospectus
     supplement, and as so supplemented to be filed pursuant to Rule 424 under
     the Act, and to comply fully with Rules 424, 430A and 462, as applicable,
     under the Act in a timely manner; and comply with the provisions of the
     Act with respect to the disposition of all securities covered by such
     Registration Statement during the applicable period in accordance with the
     intended method or methods of distribution by the sellers thereof set
     forth in such Registration Statement or supplement to the Prospectus;

               (iii)  advise each Holder promptly and, if requested by such
     Holder, confirm such advice in writing, (A) when the Prospectus or any
     Prospectus supplement or post-effective amendment has been filed, and,
     with respect to any applicable Registration Statement or any
     post-effective amendment thereto, when the same has become effective, (B)
     of any request by the Commission for post-effective amendments to the
     Registration Statement or post-effective amendments or supplements to the
     Prospectus or for additional information relating thereto, (C) of the
     issuance by the Commission of any stop order suspending the effectiveness
     of the Registration Statement under the Act or of the suspension by any
     state securities commission of the qualification of the Transfer
     Restricted Securities for offering or sale in any jurisdiction, or the
     initiation of any proceeding for any of the preceding purposes, (D) of the
     existence of any fact or the happening of any event that makes any
     statement of a material fact made in the Registration Statement, the
     Prospectus, any amendment or supplement thereto or any document
     incorporated by reference therein untrue, or that requires the making of
     any additions to or changes in the Registration Statement in order to make
     the statements therein not misleading, or that requires the making of any
     additions to or changes in the Prospectus in order to make the statements
     therein, in the light of the circumstances under which they were made, not
     misleading or (E) if a material condition or event contemplated by the
     immediately preceding clause (D) exists, has occurred or is anticipated,
     but that the disclosure in the Registration Statement or Prospectus
     necessary to supplement or correct the Registration Statement or
     Prospectus as required by clause (D) would be detrimental to the Company
     and the Guarantors, taken as a whole.  If at any time the Commission shall
     issue any stop order suspending the effectiveness of the Registration
     Statement, or any state securities commission or other regulatory
     authority shall issue an order suspending the qualification or exemption
     from qualification of the Transfer Restricted Securities under state
     securities or Blue Sky laws, the Company and the Guarantors shall use
     their respective reasonable best efforts to obtain the withdrawal or
     lifting of such order at the earliest possible time;

               (iv)  subject to Section 6(c)(i), if any fact or event
     contemplated by Section 6(c)(iii)(D) above shall exist or have occurred,
     prepare a supplement or post-effective amendment to the Registration
     Statement or related Prospectus or any document incorporated therein by
     reference or file any other required document so that, as thereafter
     delivered to the purchasers of Transfer Restricted Securities, the
     Prospectus will not contain an untrue statement of a material fact or omit
     to state any material fact necessary to make the statements therein, in
     the light of the circumstances under which they were made, not misleading;

               (v)   furnish to each Initial Purchaser in connection with such
     exchange or sale, if any, before filing with the Commission, copies of any
     Registration Statement or any Prospectus included therein or any
     amendments or supplements to any such Registration Statement or Prospectus
     (including all




                                      9
<PAGE>   11
     documents incorporated by reference after the initial filing of such
     Registration Statement), which documents will be subject to the review and
     comment of such Initial Purchasers in connection with such sale, if any,
     for a period of at least five Business Days, and the Company will not file
     any such Registration Statement or Prospectus or any amendment or
     supplement to any such Registration Statement or Prospectus (including all
     such documents incorporated by reference) to which such Holders shall
     reasonably object within five Business Days after the receipt thereof.  An
     Initial Purchaser shall be deemed to have reasonably objected to such
     filing if such Registration Statement, amendment, Prospectus or
     supplement, as applicable, as proposed to be filed, contains an untrue
     statement of a material fact or omit to state any material fact necessary
     to make the statements therein not misleading or fails to comply in any
     material respect with the applicable requirements of the Act;

               (vi)  promptly prior to the filing of any document that is to be
     incorporated by reference into a Registration Statement prior to its
     effectiveness, provide copies of such document to each Initial Purchaser
     in connection with such exchange or sale, if any, make the Company's and
     the Guarantors' representatives available for discussion of such document
     and other customary due diligence matters, and include such information in
     such document prior to the filing thereof as such Initial Purchasers may
     reasonably request;

               (vii) in connection with such Registration Statement or any
     post-effective amendment thereto subsequent to the filing thereof and
     prior to its effectiveness, make available, at reasonable times, for
     inspection by each Holder and any attorney or accountant retained by such
     Holders, all financial and other records, pertinent corporate documents of
     the Company and the Guarantors and cause the Company's and the Guarantors'
     officers, directors and employees to supply all information reasonably
     requested by any such Holder, attorney or accountant; provided, however,
     that such Persons shall first agree in writing with the Company that any
     information that is reasonably and in good faith designated by the Company
     in writing as confidential at the time of delivery of such information
     shall be kept confidential by such Persons, unless (i) disclosure of such
     information is required by court or administrative order or is necessary
     to respond to inquiries or regulatory authorities, (ii) disclosure of such
     information is required by law (including any disclosure requirements
     pursuant to federal securities laws in connection with the filing of any
     Registration Statement or the use of any prospectus referred to in this
     Agreement), (iii) such information becomes generally available to the
     public other than as a result of a disclosure or failure to safeguard by
     such Person or (iv) such information becomes lawfully available to such
     Person from a source other than the Company and such source lawfully
     obtained such information and is not otherwise bound by a confidentiality
     agreement;

               (viii)  if requested by any Initial Purchasers in connection
     with such sale, promptly include in any Registration Statement or
     Prospectus, pursuant to a supplement or post-effective amendment if
     necessary, such information as such Initial Purchasers may reasonably
     request to have included therein, including, without limitation,
     information relating to the "Plan of Distribution" of the Transfer
     Restricted Securities; and make all required filings of such Prospectus
     supplement or post-effective amendment as soon as practicable after the
     Company is notified of the matters to be included in such Prospectus
     supplement or post-effective amendment;

               (ix)  furnish to each Initial Purchaser in connection with such
     exchange or sale, without charge, at least one copy of the Registration
     Statement, as first filed with the Commission, and of each amendment
     thereto, including all documents incorporated by reference therein and all
     exhibits (including exhibits incorporated therein by reference);



                                     10
<PAGE>   12


               (x)  deliver to each Initial Purchaser and each Holder without
     charge, as many copies of the Prospectus (including each preliminary
     prospectus) and any amendment or supplement thereto as such Persons
     reasonably may request; the Company and the Guarantors hereby consent to
     the use (in accordance with law) of the Prospectus and any amendment or
     supplement thereto by each selling Holder in connection with the offering
     and the sale of the Transfer Restricted Securities covered by the
     Prospectus or any amendment or supplement thereto;

               (xi)  in connection with the Shelf Registration Statement, upon
     the request of any Holder, enter into such agreements (including
     underwriting agreements in form, scope and substance as is customary in
     underwritten offerings) and take such other reasonable actions in
     connection therewith in order to expedite or facilitate the disposition of
     the Transfer Restricted Securities pursuant to any applicable Registration
     Statement contemplated by this Agreement as may be reasonably requested by
     any Holder in connection with any sale or resale pursuant to any
     applicable Registration Statement.  In such connection, the Company and
     the Guarantors shall:

               (A)  upon request of any Initial Purchaser or Holder, furnish
          (or in the case of paragraphs (2) and (3), use its reasonable best
          efforts to cause to be furnished) to each Initial Purchaser or
          Holder, upon Consummation of the Exchange Offer or upon the
          effectiveness of the Shelf Registration Statement, as the case may
          be:

                    (1)  a certificate, dated such date, signed on behalf of
               the Company and each Guarantor by (x) the President or any Vice
               President and (y) a principal financial or accounting officer of
               the Company and such Guarantor, confirming, as of the date
               thereof, the matters set forth in Sections 6(y), 9(a) and 9(b)
               of the Purchase Agreement and such other similar matters as such
               Holders may reasonably request;

                    (2)  an opinion, dated the date of Consummation of the
               Exchange Offer or the date of effectiveness of the Shelf
               Registration Statement, as the case may be, of counsel for the
               Company and the Guarantors covering matters similar to those set
               forth in Exhibit B of the Purchase Agreement and such other
               matters as such Initial Purchaser or Holder may reasonably
               request, and in any event including a statement to the effect
               that such counsel has participated in conferences with officers
               and other representatives of the Company and the Guarantors,
               representatives of the independent public accountants for the
               Company and the Guarantors and the Initial Purchasers at which
               the contents of the Registration Statement and Prospectus were
               discussed, although such counsel is not passing upon and has not
               independently verified or assumed responsibility for the
               accuracy, completeness or fairness of such statements; and that
               such counsel advises that, on the basis of the foregoing
               (relying as to materiality to the extent such counsel deems
               appropriate upon the statements of officers and other
               representatives of the Company and the Guarantors) and without
               independent check or verification), no facts came to such
               counsel's attention that caused such counsel to believe that the
               applicable Registration Statement, at the time such Registration
               Statement or any post-effective amendment thereto became
               effective and, in the case of the Exchange Offer Registration
               Statement, as of the date of Consummation of the Exchange Offer,
               contained an untrue statement of a material fact or omitted to
               state a material fact required to be stated




                                     11
<PAGE>   13
               therein or necessary to make the statements therein not
               misleading, or that the Prospectus contained in such
               Registration Statement as of its date and, in the case of the
               opinion dated the date of Consummation of the Exchange Offer, as
               of the date of Consummation, contained an untrue statement of a
               material fact or omitted to state a material fact necessary in
               order to make the statements therein, in the light of the
               circumstances under which they were made, not misleading.
               Without limiting the foregoing, such counsel may state further
               that such counsel expresses no opinion or belief with respect
               to, assumes no responsibility for, and has not independently
               verified, the accuracy, completeness or fairness of the
               financial statements, notes and schedules and other financial
               data included in any Registration Statement contemplated by this
               Agreement or the related Prospectus or with respect to that part
               of the Registration Statement that constitutes the Statement Of
               Eligibility (Form T-1) under the TIA;

                    (3)  an opinion, dated the date of the Consummation of the
               Exchange Offer or the date of the effectiveness of the Shelf
               Registration Statement, as the case may be, of Venezuelan
               counsel of the Company covering matters similar to those set
               forth in paragraph (f) of Section 9 of the Purchase Agreement;
               and

                    (4)  a customary comfort letter, dated the date of
               Consummation of the Exchange Offer, or as of the date of
               effectiveness of the Shelf Registration Statement, as the case
               may be, from the Company's independent accountants, in the
               customary form and covering matters of the type customarily
               covered in comfort letters to underwriters in connection with
               underwritten offerings, and affirming the matters set forth in
               the comfort letters delivered pursuant to Section 9(h) of the
               Purchase Agreement; and

               (B) deliver such other documents and certificates as may be
          reasonably requested by the selling Holders to evidence compliance
          with the matters covered in clause (A) above and with any customary
          conditions contained in the any agreement entered into by the Company
          and the Guarantors pursuant to this clause (xi);

               (xii)  prior to any public offering of Transfer Restricted
     Securities, cooperate with the selling Holders and their counsel in
     connection with the registration and qualification of the Transfer
     Restricted Securities under the securities or Blue Sky laws of such
     jurisdictions as the selling Holders may request and do any and all other
     acts or things necessary or advisable to enable the disposition in such
     jurisdictions of the Transfer Restricted Securities covered by the
     applicable Registration Statement; provided, however, that neither the
     Company nor any Guarantor shall be required to register or qualify as a
     foreign corporation where it is not now so qualified or to take any action
     that would subject it to the service of process in suits or to taxation,
     other than as to matters and transactions relating to the Registration
     Statement, in any jurisdiction where it is not now so subject;

               (xiii)  in connection with any sale of Transfer Restricted
     Securities that will result in such securities no longer being Transfer
     Restricted Securities, cooperate with the Holders to facilitate the timely
     preparation and delivery of certificates representing Transfer Restricted
     Securities to be sold and not bearing any restrictive legends; and to
     register such Transfer Restricted Securities in such denominations and
     such names as the selling Holders may request at least two Business Days
     prior to such sale of Transfer Restricted Securities;




                                     12
<PAGE>   14
               (xiv)  use their respective reasonable best efforts to cause the
     disposition of the Transfer Restricted Securities covered by the
     Registration Statement to be registered with or approved by such other
     governmental agencies or authorities as may be necessary to enable the
     seller or sellers thereof to consummate the disposition of such Transfer
     Restricted Securities, subject to the proviso contained in clause (xii)
     above;

               (xv)  provide a CUSIP number for all Transfer Restricted
     Securities not later than the effective date of a Registration Statement
     covering such Transfer Restricted Securities and provide the Trustee under
     the Indenture with printed certificates for the Transfer Restricted
     Securities which are in a form eligible for deposit with The Depository
     Trust Company;

               (xvi)  otherwise use their respective reasonable best efforts to
     comply with all applicable rules and regulations of the Commission, and
     make generally available to its security holders with regard to any
     applicable Registration Statement, as soon as practicable, a consolidated
     earnings statement meeting the requirements of Rule 158 (which need not be
     audited) covering a twelve-month period beginning after the effective date
     of the Registration Statement (as such term is defined in paragraph (c) of
     Rule 158 under the Act);

               (xvii)  cause the Indenture to be qualified under the TIA not
     later than the effective date of the first Registration Statement required
     by this Agreement and, in connection therewith, cooperate with the Trustee
     and the Holders to effect such changes to the Indenture as may be required
     for such Indenture to be so qualified in accordance with the terms of the
     TIA; and execute and use its best efforts to cause the Trustee to execute,
     all documents that may be required to effect such changes and all other
     forms and documents required to be filed with the Commission to enable
     such Indenture to be so qualified in a timely manner; and

               (xviii)  provide promptly to each Holder, upon request, each
     document filed with the Commission pursuant to the requirements of Section
     13 or Section 15(d) of the Exchange Act.

          (d)  Restrictions on Holders.  Each Holder agrees by acquisition of a
Transfer Restricted Security that, upon receipt of the notice referred to in
Section 6(c)(iii)(C) or any notice from the Company of the existence of any
fact or circumstance of the kind described in Section 6(c)(iii)(D) or Section
6(c)(iii)(E) hereof (in each case, a "SUSPENSION NOTICE"), such Holder will
forthwith discontinue disposition of Transfer Restricted Securities pursuant to
the applicable Registration Statement until (i) such Holder has received copies
of the supplemented or amended Prospectus contemplated by Section 6(c)(iv)
hereof, or (B) such Holder is advised in writing by the Company that the use of
the Prospectus may be resumed, and has received copies of any additional or
supplemental filings that are incorporated by reference in the Prospectus (in
each case, the "RECOMMENCEMENT DATE").  Each Holder receiving a Suspension
Notice hereby agrees that it will either (i) destroy any Prospectuses, other
than permanent file copies, then in such Holder's possession which have been
replaced by the Company with more recently dated Prospectuses or (ii) deliver
to the Company (at the Company's expense) all copies, other than permanent file
copies, then in such Holder's possession of the Prospectus covering such
Transfer Restricted Securities that was current at the time of receipt of the
Suspension Notice.  Notwithstanding anything in this Agreement to the contrary,
if the Company shall issue a Suspension Notice based on an event or
circumstances contemplated by Section 1(c)(iii)(E), the Company and the
Guarantors may delay any filing with the Commission that would otherwise be
required by this Agreement to maintain the effectiveness of the Registration
Statement, to




                                     13
<PAGE>   15
amend the Registration Statement or to correct or Supplement the Prospectus,
for a period of time not to exceed 30 consecutive days from the date of the
Suspension Notice or a maximum of 60 days in any twelve-month period.  Promptly
after the Company determines that the event or circumstance contemplated by
Section 6(c)(iii)(E) no longer exists, and in any event promptly after the
expiration of any delay permitted by the preceding sentence, the Company shall
prepare and file with the Commission the amendments to the Registration
Statement and supplements to the Prospectus required by Section 6(c)(i) and
Section 6(c)(ii).  The time period regarding the effectiveness of such
Registration Statement set forth in Section 3 or 4 hereof, as applicable, shall
be extended by a number of days equal to the number of days in the period from
and including the date of delivery of the Suspension Notice to the date of
delivery of the Recommencement Date.

SECTION 7.       REGISTRATION EXPENSES

          (a)  All expenses incident to the Company's and the Guarantor(s)'
performance of or compliance with this Agreement will be borne by the Company,
regardless of whether a Registration Statement becomes effective, including
without limitation: (i) all registration and filing fees and expenses; (ii) all
fees and expenses of compliance with federal securities and state Blue Sky or
securities laws; (iii) all expenses of printing (including printing
certificates for the Exchange Notes to be issued in the Exchange Offer and
printing of Prospectuses), messenger and delivery services and telephone; (iv)
all fees and disbursements of counsel for the Company, the Guarantors and the
Holders of Transfer Restricted Securities; (v) all application and filing fees
in connection with listing the Exchange Notes on a national securities exchange
or automated quotation system pursuant to the requirements hereof; and (vi) all
fees and disbursements of independent certified public accountants of the
Company and the Guarantors (including the expenses of any special audit and
comfort letters required by or incident to such performance).

          The Company will, in any event, bear its and the Guarantors' internal
expenses (including, without limitation, all salaries and expenses of its
officers and employees performing legal or accounting duties), the expenses of
any annual audit and the fees and expenses of any Person, including special
experts, retained by the Company or the Guarantors.

          (b)  In connection with any Registration Statement required by this
Agreement (including, without limitation, the Exchange Offer Registration
Statement and the Shelf Registration Statement), the Company and the Guarantors
will reimburse the Initial Purchasers and the Holders of Transfer Restricted
Securities who are tendering Notes into in the Exchange Offer and/or selling or
reselling Notes or Exchange Notes pursuant to the "Plan of Distribution"
contained in the Exchange Offer Registration Statement or the Shelf
Registration Statement, as applicable, for the reasonable fees and
disbursements of not more than one counsel to be selected by the Initial
Purchasers.

SECTION 8.       INDEMNIFICATION

          (a)  The Company and the Guarantors agree, jointly and severally, to
indemnify and hold harmless each Holder, its directors, officers and each
Person, if any, who controls such Holder (within the meaning of Section 15 of
the Act or Section 20 of the Exchange Act), from and against any and all
losses, claims, damages, liabilities, judgments, (including without limitation,
any legal or other expenses incurred in connection with investigating or
defending any matter, including any action that could give rise to any such
losses, claims, damages, liabilities or judgments) caused by any untrue
statement or alleged untrue statement




                                     14
<PAGE>   16
of a material fact contained in any Registration Statement, preliminary
prospectus or Prospectus (or any amendment or supplement thereto) provided by
the Company to any Holder or any prospective purchaser of Exchange Notes or
registered Notes, or caused by any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, except insofar as such losses, claims,
damages, liabilities or judgments are caused by an untrue statement or omission
or alleged untrue statement or omission that is based upon information relating
to any of the Holders furnished in writing to the Company by any of the
Holders.

          (b)  Each Holder of Transfer Restricted Securities agrees, severally
and not jointly, to indemnify and hold harmless the Company and the Guarantors,
and their respective directors and officers, and each person, if any, who
controls (within the meaning of Section 15 of the Act or Section 20 of the
Exchange Act) the Company, or the Guarantors to the same extent as the
foregoing indemnity from the Company and the Guarantors set forth in Section
8(a) above, but only with reference to information relating to such Holder
furnished in writing to the Company by such Holder expressly for use in any
Registration Statement.  In no event shall any Holder, its directors, officers
or any Person who controls such Holder be liable or responsible for any amount
in excess of the amount by which the total amount received by such Holder with
respect to its sale of Transfer Restricted Securities pursuant to a
Registration Statement exceeds (i) the amount paid by such Holder for such
Transfer Restricted Securities and (ii) the amount of any damages that such
Holder, its directors, officers or any Person who controls such Holder has
otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission.

          (c)  In case any action shall be commenced involving any person in
respect of which indemnity may be sought pursuant to Section 8(a) or 8(b) (the
"INDEMNIFIED PARTY"), the indemnified party shall promptly notify the person
against whom such indemnity may be sought (the "INDEMNIFYING PERSON") in
writing and the indemnifying party shall assume the defense of such action,
including the employment of counsel reasonably satisfactory to the indemnified
party and the payment of all fees and expenses of such counsel, as incurred
(except that in the case of any action in respect of which indemnity may be
sought pursuant to both Sections 8(a) and 8(b), a Holder shall not be required
to assume the defense of such action pursuant to this Section 8(c), but may
employ separate counsel and participate in the defense thereof, but the fees
and expenses of such counsel, except as provided below, shall be at the expense
of the Holder).  Any indemnified party shall have the right to employ separate
counsel in any such action and participate in the defense thereof, but the fees
and expenses of such counsel shall be at the expense of the indemnified party
unless (i) the employment of such counsel shall have been specifically
authorized in writing by the indemnifying party, (ii) the indemnifying party
shall have failed to assume the defense of such action or employ counsel
reasonably satisfactory to the indemnified party or (iii) the named parties to
any such action (including any impleaded parties) include both the indemnified
party and the indemnifying party, and the indemnified party shall have been
advised by such counsel that there may be one or more legal defenses available
to it which are different from or additional to those available to the
indemnifying party and that, as a matter of professional responsibility, such
counsel is unable to represent both the indemnifying and indemnified party (in
which case the indemnifying party shall not have the right to assume the
defense of such action on behalf of the indemnified party).  In any such case,
the indemnifying party shall not, in connection with any one action or separate
but substantially similar or related actions in the same jurisdiction arising
out of the same general allegations or circumstances, be liable for the fees
and expenses of more than one separate firm of attorneys (in addition to any
local counsel) for all indemnified parties and all such fees and expenses shall
be reimbursed as they are incurred.  Such firm shall be designated in writing
by a majority of the Holders, in the case of the parties indemnified pursuant
to Section 8(a), and by the Company and




                                     15
<PAGE>   17
Guarantors, in the case of parties indemnified pursuant to Section 8(b). The
indemnifying party shall indemnify and hold harmless the indemnified party from
and against any and all losses, claims, damages, liabilities and judgments by
reason of any settlement of any action (i) effected with its written consent or
(ii) effected in good faith without its written consent if the settlement is
entered into more than 20 Business Days after the indemnifying party shall have
received a request from the indemnified party for reimbursement for the fees
and expenses of counsel (in any case where such fees and expenses are at the
expense of the indemnifying party) and, prior to the date of such settlement,
the indemnifying party shall have failed to comply with such reimbursement
request unless within 30 days after such reimbursement request is received, the
indemnifying party shall have made a good faith written challenge to the
reasonableness of the amount or nature of the reimbursement requested or
sufficiency of the documentation supporting the reimbursement requested (which
challenge shall set forth the amount or nature of the requested reimbursement
which the indemnifying party in good faith believes to be reasonable or the
basis for the good faith claims as to the insufficiency of any supporting
documentation), in which event this clause (ii) shall apply only if, and to the
extent that, such indemnifying party shall not have reimbursed the indemnified
party for the amount which is not being so challenged.   No indemnifying party
shall, without the prior written consent of the indemnified party, effect any
settlement or compromise of, or consent to the entry of  judgment with respect
to, any pending or threatend action in respect of which the indemnified party
is or could have been a party and indemnity or contribution may be or could
have been sought hereunder by the indemnified party, unless such settlement,
compromise or judgment (i) includes an unconditional release of the indemnified
party from all liability on claims that are or could have been the subject
matter of such action and (ii) does not include a statement as to or an
admission of fault, culpability or a failure to act, by or on behalf of the
indemnified party.

          (d)  To the extent that the indemnification provided for in this
Section 8 is unavailable to an indemnified party in respect of any losses,
claims, damages, liabilities or judgments referred to therein, then each
indemnifying party, in lieu of indemnifying such indemnified party, shall
contribute to the amount paid or payable by such indemnified party as a result
of such losses, claims, damages, liabilities or judgments (i) in such
proportion as is appropriate to reflect the relative benefits received by the
Company and the Guarantors, on the one hand, and the Holders, on the other
hand, from their sale of Transfer Restricted Securities or (ii) if the
allocation provided by clause 8(d)(i) is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause 8(d)(i) above but also the relative fault of the Company
and the Guarantors, on the one hand, and of the Holder, on the other hand, in
connection with the statements or omissions which resulted in such losses,
claims, damages, liabilities or judgments, as well as any other relevant
equitable considerations.  The relative fault of the Company and the
Guarantors, on the one hand, and of the Holder, on the other hand, shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of a material fact or the omission or alleged omission to
state a material fact relates to information supplied by the Company or such
Guarantor, on the one hand, or by the Holder, on the other hand, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such statement or omission.  The amount paid or payable by a
party as a result of the losses, claims, damages, liabilities and judgments
referred to above shall be deemed to include, subject to the limitations set
forth in the second paragraph of Section 8(a), any legal or other fees or
expenses reasonably incurred by such party in connection with investigating or
defending any action or claim.




                                     16
<PAGE>   18
          The Company, the Guarantors and each Holder agree that it would not
be just and equitable if contribution pursuant to this Section 8(d) were
determined by pro rata allocation (even if the Holders were treated as one
entity for such purpose) or by any other method of allocation which does not
take account of the equitable considerations referred to in the immediately
preceding paragraph.  The amount paid or payable by an indemnified party as a
result of the losses, claims, damages, liabilities or judgments referred to in
the immediately preceding paragraph shall be deemed to include, subject to the
limitations set forth above, any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any
matter, including any action that could have given rise to such losses, claims,
damages, liabilities or judgments.  Notwithstanding the provisions of this
Section 8, no Holder, its directors, its officers or any Person, if any, who
controls such Holder shall be required to contribute, in the aggregate, any
amount in excess of the amount by which the total received by such Holder with
respect to the sale of Transfer Restricted Securities pursuant to a
Registration Statement exceeds (i) the amount paid by such Holder for such
Transfer Restricted Securities and (ii) the amount of any damages which such
Holder has otherwise been required to pay by reason of such untrue or alleged
untrue statement or omission or alleged omission.  No person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation.  The Holders' obligations to contribute pursuant
to this Section 8(c) are several in proportion to the respective principal
amount of Transfer Restricted Securities held by each Holder hereunder and not
joint.

SECTION 9.       RULE 144A AND RULE 144

          The Company and each Guarantor agrees with each Holder, for so long
as any Transfer Restricted Securities remain outstanding and during any period
in which the Company or such Guarantor (i) is not subject to Section 13 or
15(d) of the Exchange Act, to make available, upon request of any Holder, to
such Holder or beneficial owner of Transfer Restricted Securities in connection
with any sale thereof and any prospective purchaser of such Transfer Restricted
Securities designated by such Holder or beneficial owner, the information
required by Rule 144A(d)(4) under the Act in order to permit resales of such
Transfer Restricted Securities pursuant to Rule 144A, and (ii) is subject to
Section 13 or 15 (d) of the Exchange Act, to make all filings required thereby
in a timely manner in order to permit resales of such Transfer Restricted
Securities pursuant to Rule 144.


SECTION 10.      MISCELLANEOUS

          (a)  Remedies.  The Company and the Guarantors acknowledge and agree
that any failure by the Company and/or the Guarantors to comply with their
respective obligations under Sections 3 and 4 hereof may result in material
irreparable injury to the Initial Purchasers or the Holders for which there is
no adequate remedy at law, that it will not be possible to measure damages for
such injuries precisely and that, in the event of any such failure, the Initial
Purchasers or any Holder may obtain such relief as may be required to
specifically enforce the Company's and the Guarantor's obligations under
Sections 3 and 4 hereof.  The Company and the Guarantors further agree to waive
the defense in any action for specific performance that a remedy at law would
be adequate.

          (b)  No Inconsistent Agreements.  Neither the Company nor any
Guarantor will, on or after the date of this Agreement, enter into any
agreement with respect to its securities that is inconsistent with the rights
granted to the Holders in this Agreement or otherwise conflicts with the
provisions hereof.  Neither the Company nor any Guarantor has previously
entered into any agreement granting any registration rights




                                     17
<PAGE>   19
with respect to its debt securities to any Person.  The rights granted to the
Holders hereunder do not in any way conflict with and are not inconsistent with
the rights granted to the holders of the Company's and the Guarantors' debt
securities under any agreement in effect on the date hereof.

          (c)  Amendments and Waivers.  The provisions of this Agreement may
not be amended, modified or supplemented, and waivers or consents to or
departures from the provisions hereof may not be given unless (i) in the case
of Section 5 hereof and this Section 10(c)(i), the Company has obtained the
written consent of Holders of all outstanding Transfer Restricted Securities
and (ii) in the case of all other provisions hereof, the Company has obtained
the written consent of Holders of a majority of the outstanding principal
amount of Transfer Restricted Securities (excluding Transfer Restricted
Securities held by the Company or its Affiliates).  Notwithstanding the
foregoing, a waiver or consent to departure from the provisions hereof that
relates exclusively to the rights of Holders whose Transfer Restricted
Securities are being tendered pursuant to the Exchange Offer, and that does not
affect directly or indirectly the rights of other Holders whose Transfer
Restricted Securities are not being tendered pursuant to such Exchange Offer,
may be given by the Holders of a majority of the outstanding principal amount
of Transfer Restricted Securities subject to such Exchange Offer, and vice
versa.

          (d)  Third Party Beneficiary.  The Holders shall be third party
beneficiaries to the agreements made hereunder between the Company and the
Guarantors, on the one hand, and the Initial Purchasers, on the other hand, and
shall have the right to enforce such agreements directly to the extent they may
deem such enforcement necessary or advisable to protect its rights or the
rights of Holders hereunder.

          (e) Notices.  All notices and other communications provided for or
permitted hereunder shall be made in writing by hand-delivery, first-class mail
(registered or certified, return receipt requested), telex, telecopier, or air
courier guaranteeing overnight delivery:

               (i)  if to a Holder, at the address set forth on the records of
     the Registrar under the Indenture, with a copy to the Registrar under the
     Indenture; and

               (ii) if to the Company or the Guarantors:

                    Grey Wolf, Inc.
                    10370 Richmond Avenue, Suite 600
                    Houston, Texas  77042
                    Telecopier No.:  (713) 435-6100
                    Attention:  Chief Financial Officer

                    With a copy to:

                    Porter & Hedges, L.L.P.
                    700 Louisiana Street, Suite 3500
                    Houston, Texas 77002
                    Telecopier No.:  (713) 226-0600
                    Attention:  Nick D. Nicholas




                                     18
<PAGE>   20
          All such notices and communications shall be deemed to have been duly
given:  at the time delivered by hand, if personally delivered; five Business
Days after being deposited in the mail, postage prepaid, if mailed; when
receipt acknowledged, if telecopied; and on the next business day, if timely
delivered to an air courier guaranteeing overnight delivery.

          Copies of all such notices, demands or other communications shall be
concurrently delivered by the Person giving the same to the Trustee at the
address specified in the Indenture.

          (f)  Successors and Assigns.  This Agreement shall inure to the
benefit of and be binding upon the successors and assigns of each of the
parties, including without limitation and without the need for an express
assignment, subsequent Holders; provided, that nothing herein shall be deemed
to permit any assignment, transfer or other disposition of Transfer Restricted
Securities in violation of the terms hereof or of the Purchase Agreement or the
Indenture.  If any transferee of any Holder shall acquire Transfer Restricted
Securities in any manner, whether by operation of law or otherwise, such
Transfer Restricted Securities shall be held subject to all of the terms of
this Agreement, and by taking and holding such Transfer Restricted Securities
such Person shall be conclusively deemed to have agreed to be bound by and to
perform all of the terms and provisions of this Agreement, including the
restrictions on resale set forth in this Agreement and, if applicable, the
Purchase Agreement, and such Person shall be entitled to receive the benefits
hereof.

          (g)  Counterparts.  This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

          (h)  Headings.  The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

          (i)  Governing Law.  THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD
TO THE CONFLICT OF LAW RULES THEREOF.

          (j)  Severability.  In the event that any one or more of the
provisions contained herein, or the application thereof in any circumstance, is
held invalid, illegal or unenforceable, the validity, legality and
enforceability of any such provision in every other respect and of the
remaining provisions contained herein shall not be affected or impaired
thereby.

          Entire Agreement.  This Agreement is intended by the parties as a
final expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect
of the subject matter contained herein.  There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein
with respect to the registration rights granted with respect to the Transfer
Restricted Securities.  This Agreement supersedes all prior agreements and
understandings between the parties with respect to such subject matter.

                [Remainder of page is intentionally left blank.]




                                     19
<PAGE>   21
       IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first written above.

                                  GREY WOLF, INC.


                                  By:  /s/ DAVID W. WEHLMANN
                                       ---------------------
                                  Name:  David W. Wehlmann
                                  Title: Senior Vice President and 
                                         Chief Financial Officer


                                  GREY WOLF DRILLING COMPANY


                                  By:  /s/ DAVID W. WEHLMANN
                                       ---------------------
                                  Name:  David W. Wehlmann
                                  Title: Senior Vice President and 
                                         Chief Financial Officer


                                  DI ENERGY, INC.


                                  By:  /s/ DAVID W. WEHLMANN
                                       ---------------------
                                  Name:  David W. Wehlmann
                                  Title: Senior Vice President and 
                                         Chief Financial Officer


                                  GREY WOLF INTERNATIONAL, INC.


                                  By:  /s/ DAVID W. WEHLMANN
                                       ---------------------
                                  Name:  David W. Wehlmann
                                  Title: Senior Vice President and 
                                         Chief Financial Officer


                                  MURCO DRILLING CORPORATION


                                  By:  /s/ DAVID W. WEHLMANN
                                       ---------------------
                                  Name:  David W. Wehlmann
                                  Title: Secretary





<PAGE>   22

DONALDSON, LUFKIN & JENRETTE
    SECURITIES CORPORATION
LEHMAN BROTHERS INC.

PRUDENTIAL SECURITIES INCORPORATED



By:  DONALDSON, LUFKIN & JENRETTE
        SECURITIES CORPORATION



By: /s/ CRAIG KLAASMEYER
    --------------------
Name:  Craig Klaasmeyer
Title: Vice President





<PAGE>   23
                                   EXHIBIT A

                              NOTICE OF FILING OF
                     EXCHANGE OFFER REGISTRATION STATEMENT


To:       Donaldson, Lufkin & Jenrette Securities Corporation
          277 Park Avenue
          New York, New York  10172
          Attention:  Louise Guarneri (Compliance Department)
          Fax: (212) 892-7272

From:     Grey Wolf, Inc.
          8 7/8% Senior Notes due 2007, Series B

Date:     _______________, 1998

     For your information only (NO ACTION REQUIRED):

     Today, ___________, 199__, we filed [an Exchange Registration Statement/a
Shelf Registration Statement] with the Securities and Exchange Commission.  We
currently expect this registration statement to be declared effective within
_____ business days of the date hereof.





                                   Exhibit A
<PAGE>   24
                                   SCHEDULE A
                               INITIAL GUARANTORS

<TABLE>
<CAPTION>
            NAME OF GUARANTOR                      STATE OF INCORPORATION
     -----------------------------------------     ----------------------
     <S>                                           <C>
     Grey Wolf Drilling Company                            Texas
     Murco Drilling Corporation (a wholly-                Delaware
     owned subsidiary of Grey Wolf
     Drilling Company)
     Grey Wolf International, Inc.                         Texas
     DI Energy, Inc.                                       Texas
</TABLE>




                                  Schedule A

<PAGE>   1
                                                                     EXHIBIT 4.3




================================================================================





                                 GREY WOLF, INC.
                                       AND
                                   GUARANTORS

                                   $75,000,000
                     8-7/8% Senior Notes due 2007, Series B



                               --------------------



                                    INDENTURE



                             Dated as of May 8, 1998



                               --------------------



                    CHASE BANK OF TEXAS, NATIONAL ASSOCIATION

                                     Trustee







================================================================================




<PAGE>   2






                              CROSS-REFERENCE TABLE

         Reconciliation and tie between The Trust Indenture Act as amended, and
The Indenture dated as of May 8, 1998.

<TABLE>
<CAPTION>


             TIA                                                                        Indenture
           Section                                                                       Section
           -------                                                                      ---------
<S>                                                                                     <C>
                     310(a)(1)  ...........................................                7.10
                        (a)(2)  ...........................................                7.10
                        (a)(3)  ...........................................                 N/A
                        (a)(4)  ...........................................                 N/A
                        (a)(5)  ...........................................                7.10
                           (b)  ...........................................              7.8; 7.10
                           (c)  ...........................................                 N/A
                        311(a)  ...........................................                7.11
                           (b)  ...........................................                7.11
                           (c)  ...........................................                 N/A
                        312(a)  ...........................................                 2.7
                           (b)  ...........................................                12.6
                           (c)  ...........................................                12.6
                        313(a)  ...........................................                 7.6
                        (b)(1)  ...........................................                 N/A
                        (b)(2)  ...........................................                 7.6
                           (c)  ...........................................              7.6, 12.5
                           (d)  ...........................................                 7.6
                        314(a)  ...........................................             4.2; 4.22;
                                                                                           12.5
                           (b)  ...........................................                 N/A
                        (c)(1)  ...........................................             12.1, 12.2
                        (c)(2)  ..........................................              12.1; 12.2
                        (c)(3)  ...........................................                 N/A
                           (d)  ...........................................                 N/A
                           (e)  ...........................................             12.1; 12.2
                           (f)  ...........................................                 N/A
                        315(a)  ...........................................                 7.1
                           (b)  ...........................................           4.22; 7.5; 12.2
                           (c)  ...........................................                 7.1
                           (d)  ...........................................                 7.1
                           (e)  ...........................................                6.11
        316(a)(last  sentence)  ...........................................                 2.9
                     (a)(1)(A)  ...........................................                 6.5
                     (a)(1)(B)  ...........................................                 6.4
                        (a)(2)  ...........................................                 N/A
                           (b)  ...........................................                 6.7
                           (c)  ...........................................                10.5
                     317(a)(1)  ...........................................              6.3; 6.8
                        (a)(2)  ...........................................                 6.9
                           (b)  ...........................................                 2.4
</TABLE>

                                       C-1

<PAGE>   3


<TABLE>
<CAPTION>




             TIA                                                                        Indenture
           Section                                                                       Section
           Section                                                                       Section
           -------                                                                      ---------
<S>                                                                                     <C>
                        318(a)  ...........................................                12.4

</TABLE>

                            N/A Means Not Applicable.

- -------------------

Note: This Cross-Reference Table shall not, for any purposes, be deemed to be
part of this Indenture.


                                       C-2

<PAGE>   4


                              TABLE OF CONTENTS


<TABLE>
<CAPTION>

                                                

                                                                                                               Page
                                                                                                               ----


<S>                   <C>                                                                                      <C>
ARTICLE 1.            Definitions and Incorporation by Reference..................................................1
         SECTION 1.1.            Definitions......................................................................1
         SECTION 1.2.            Incorporation by Reference of Trust Indenture Act...............................21
         SECTION 1.3.            Rules of Construction...........................................................21

ARTICLE 2.            THE SENIOR NOTES...........................................................................22
         SECTION 2.1.            Form and Dating.................................................................22
         SECTION 2.2.            Execution and Authentication....................................................24
         SECTION 2.3.            Registrar and Paying Agent......................................................24
         SECTION 2.4.            Paying Agent to Hold Money in Trust.............................................25
         SECTION 2.5.            Computation of Interest.........................................................25
         SECTION 2.6.            Transfer and Exchange...........................................................25
         SECTION 2.7.            Holder Lists....................................................................33
         SECTION 2.8.            Replacement of Senior Notes.....................................................34
         SECTION 2.9.            Outstanding Senior Notes........................................................34
         SECTION 2.10.           Reserved........................................................................34
         SECTION 2.11.           Cancellation....................................................................34
         SECTION 2.12.           Payment of Interest; Interest Rights Preserved..................................35
         SECTION 2.13.           Authorized Denominations........................................................36
         SECTION 2.14.           CUSIP Number....................................................................36
         SECTION 2.15.           Treasury Senior Notes...........................................................36

ARTICLE 3.            Redemption.................................................................................36
         SECTION 3.1.            Notices to Trustee..............................................................36
         SECTION 3.2.            Selection of Senior Notes To Be Redeemed........................................36
         SECTION 3.3.            Notice of Redemption............................................................37
         SECTION 3.4.            Effect of Notice of Redemption..................................................38
         SECTION 3.5.            Deposit of Redemption Price.....................................................38
         SECTION 3.6.            Senior Notes Redeemed in Part...................................................38
         SECTION 3.7.            Optional Redemption.............................................................39

ARTICLE 4.            Covenants..................................................................................39
         SECTION 4.1.            Payment of Senior Notes.........................................................39
         SECTION 4.2.            Commission Reports..............................................................40
         SECTION 4.3.            Limitation on Indebtedness......................................................40
         SECTION 4.4.            Limitation on Subsidiary Indebtedness and Preferred Stock.......................40
         SECTION 4.5.            Limitation on Restricted Payments...............................................41
         SECTION 4.6.            Limitations on Dividends and Other Payment Restrictions
                                 Affecting Subsidiaries..........................................................43
         SECTION 4.7.            Limitation on Asset Sales.......................................................43
         SECTION 4.8.            Limitation on Transactions with Affiliates......................................46
         SECTION 4.9.            Change of Control...............................................................47
         SECTION 4.10.           Limitation on Liens.............................................................49
         SECTION 4.11.           Limitation on Guarantees by Guarantors..........................................49
         SECTION 4.12.           Unrestricted Subsidiaries.......................................................49
         SECTION 4.13.           Limitation on Sale and Lease-Back Transactions..................................50
         SECTION 4.14.           Limitation on Line of Business..................................................50
         SECTION 4.15.           Limitation on Restrictive Covenants.............................................50

</TABLE>

                                       i
<PAGE>   5

<TABLE>

<S>                   <C>                                                                                      <C>
         SECTION 4.16.           Limitation on Redemptions and Other Repayments of
                                 Notes and Series A Notes........................................................50
         SECTION 4.17.           Maintenance of Office or Agency.................................................51
         SECTION 4.18.           Money for the Senior Note Payments to be Held in Trust..........................52
         SECTION 4.19.           Corporate Existence.............................................................52
         SECTION 4.20.           Maintenance of Property.........................................................52
         SECTION 4.21.           Payment of Taxes and Other Claims...............................................52
         SECTION 4.22.           Compliance Certificate; Notice of Default or Event of
                                 Default.........................................................................53
         SECTION 4.23.           Further Instruments and Acts....................................................53
         SECTION 4.24.           Prohibition on Company and Guarantors Becoming
                                 Investment Companies............................................................53
         SECTION 4.25.           Stay, Extension and Usury Laws..................................................53

ARTICLE 5             Consolidation, Merger, Conveyance, Lease or Transfer.......................................54
         SECTION 5.1.            Consolidation, Merger, Conveyance, Lease or Transfer............................54
         SECTION 5.2.            Officers' Certificate and Opinion of Counsel....................................55
         SECTION 5.3.            Substitution of Surviving Entity................................................55

ARTICLE 6             Defaults and Remedies......................................................................56
         SECTION 6.1.            Events of Default...............................................................56
         SECTION 6.2.            Acceleration....................................................................57
         SECTION 6.3.            Other Remedies..................................................................58
         SECTION 6.4.            Waiver of Past Defaults.........................................................59
         SECTION 6.5.            Control by Majority.............................................................59
         SECTION 6.6.            Limitation on Suits.............................................................59
         SECTION 6.7.            Rights of Holders to Receive Payment............................................59
         SECTION 6.8.            Collection Suit by Trustee......................................................60
         SECTION 6.9.            Trustee May File Proofs of Claim................................................60
         SECTION 6.10.           Priorities......................................................................61
         SECTION 6.11.           Undertaking for Costs...........................................................61
         SECTION 6.12.           Restoration of Rights and Remedies..............................................61
         SECTION 6.13.           Rights and Remedies Cumulative..................................................62
         SECTION 6.14.           Delay or Omission Not Waiver....................................................62

ARTICLE 7             Trustee....................................................................................62
         SECTION 7.1.            Duties of Trustee...............................................................62
         SECTION 7.2.            Rights of Trustee...............................................................63
         SECTION 7.3.            Individual Rights of Trustee....................................................64
         SECTION 7.4.            Trustee's Disclaimer............................................................64
         SECTION 7.5.            Notice of Defaults..............................................................65
         SECTION 7.6.            Reports by Trustee to Holders...................................................65
         SECTION 7.7.            Compensation and Indemnity......................................................65
         SECTION 7.8.            Replacement of Trustee..........................................................66
         SECTION 7.9.            Successor Trustee by Merger.....................................................67
         SECTION 7.10.           Eligibility; Disqualification...................................................67
         SECTION 7.11.           Preferential Collection of Claims Against Company...............................68

ARTICLE 8             Satisfaction and Discharge.................................................................68
         SECTION 8.1.            Satisfaction and Discharge......................................................68
         SECTION 8.2.            Application of Trust Money......................................................69
         SECTION 8.3.            Repayment to the Company........................................................69
         SECTION 8.4.            Reinstatement...................................................................70

</TABLE>



                                      ii

<PAGE>   6
<TABLE>


<S>                   <C>                                                                                      <C>
ARTICLE 9             Defeasance.................................................................................70
         SECTION 9.1.            Company's Option to Effect Defeasance or Covenant
                                 Defeasance......................................................................70
         SECTION 9.2.            Defeasance and Discharge........................................................70
         SECTION 9.3.            Covenant Defeasance.............................................................71
         SECTION 9.4.            Conditions to Defeasance or Covenant Defeasance.................................71
         SECTION 9.5.            Deposited Money and U. S. Government Obligations to be
                                 Held in Trust; Miscellaneous Provisions.........................................72
         SECTION 9.6.            Repayment to Company............................................................73
         SECTION 9.7.            Reinstatement...................................................................73

ARTICLE 10            Amendments.................................................................................74
         SECTION 10.1.           Without Consent of Holders......................................................74
         SECTION 10.2.           With Consent of Holders.........................................................74
         SECTION 10.3.           Effect of Supplemental Indentures...............................................75
         SECTION 10.4.           Compliance with Trust Indenture Act.............................................75
         SECTION 10.5.           Revocation and Effect of Consents and Waivers...................................76
         SECTION 10.6.           Notation on or Exchange of Senior Notes.........................................76
         SECTION 10.7.           Trustee To Execute Supplemental Indentures......................................76
         SECTION 10.8.           Payment for Consent.............................................................77

ARTICLE 11            Guarantees.................................................................................77
         SECTION 11.1.           Guarantees......................................................................77
         SECTION 11.2.           Limitation on Liability.........................................................80
         SECTION 11.3.           Execution and Delivery of Guarantees............................................80
         SECTION 11.4.           When a Guarantor May Merge, etc.................................................80
         SECTION 11.5.           No Waiver.......................................................................81
         SECTION 11.6.           Modification....................................................................81
         SECTION 11.7.           Release of Guarantor............................................................81
         SECTION 11.8.           Execution of Supplemental Indentures for Future Guarantors......................81

ARTICLE 12            Miscellaneous..............................................................................82
         SECTION 12.1.           Compliance Certificates and Opinions............................................82
         SECTION 12.2.           Form of Documents Delivered to Trustee..........................................82
         SECTION 12.3.           Acts of Holders.................................................................83
         SECTION 12.4.           Trust Indenture Act Controls....................................................84
         SECTION 12.5.           Notices.........................................................................85
         SECTION 12.6.           Communication by Holders with Other Holders.....................................86
         SECTION 12.7.           Rules by Trustee, Paying Agent and Registrar....................................86
         SECTION 12.8.           Payments on Business Days.......................................................86
         SECTION 12.9.           GOVERNING LAW...................................................................86
         SECTION 12.10.          No Recourse Against Others......................................................86
         SECTION 12.11.          Submission to Jurisdiction; Appointment of Agent for Service 
                                 of Process; Waiver of Immunities................................................86
         SECTION 12.12.          Successors......................................................................87
         SECTION 12.13.          Multiple Originals..............................................................88
         SECTION 12.14.          Table of Contents; Headings.....................................................88

</TABLE>

                                      iii

<PAGE>   7

<TABLE>

<S>                   <C>
EXHIBIT A             Form of Global Senior Note

EXHIBIT B-1           Form of Certificate For Exchange or Registration of Transfer
                      From U.S. Global Note To Regulation S Global Note

EXHIBIT B-2           Form of Certificate For Exchange or Registration of Transfer
                      From Regulation S Global Note To U.S. Global Note

EXHIBIT B-3           Form of Certificate For Exchange or Registration of Transfer
                      of Definitive Senior Notes

EXHIBIT B-4           Form of Certificate For Exchange or Registration of Transfer From U.S.
                      Global Note or Regulation S Permanent Global Note To Definitive Senior
                      Note

EXHIBIT C             Form of Supplemental Indenture

</TABLE>


                                       iv
<PAGE>   8




                  INDENTURE dated as of May 8, 1998, among Grey Wolf, Inc., a
Texas corporation (the "Company"), certain of the Company's subsidiaries
signatory hereto (each, a "Guarantor", collectively, the "Guarantors") and Chase
Bank of Texas, National Association, a national banking association, as trustee
(the "Trustee").

                                    RECITALS

                  The Company has duly authorized the creation and issuance of
its 8-7/8% Senior Notes due 2007, Series B (the "Initial Senior Notes") of
substantially the tenor and amount hereinafter set forth; and to provide
therefor and for, if and when issued as further evidence of the Company's
indebtedness and in substitution for the Initial Senior Notes pursuant to this
Indenture and the Registration Rights Agreement (as defined herein), the
Company's 8-7/8% Senior Notes due 2007, Series B (the "Exchange Notes," and
together with the Initial Senior Notes, the "Senior Notes"), the Company has
duly authorized the execution and delivery of this Indenture.

                  All things necessary to make the Senior Notes, when executed
by the Company and authenticated and delivered by the Trustee hereunder and duly
issued by the Company, the valid obligations of the Company, and to make this
Indenture a valid instrument of the Company and the Guarantors, in accordance
with their respective terms, have been done.

                  NOW, THEREFORE, THIS INDENTURE WITNESSETH, that, for and in
consideration of the premises and the purchase of the Initial Senior Notes by
the Holders thereof, it is mutually covenanted and agreed, for the equal and
proportionate benefit of all Holders of the Senior Notes, as follows:

                                   ARTICLE 1.

                   Definitions and Incorporation by Reference

SECTION 1.1.  Definitions.

         "Acquired Indebtedness" means, with respect to any specified Person,
Indebtedness of any other Person existing at the time such other Person merged
with or into or became a subsidiary of such specified Person, including
Indebtedness incurred in connection with, or in contemplation of, such other
Person merging with or into or becoming a subsidiary of such specified Person,
but excluding Indebtedness which is extinguished, retired or repaid in
connection with such other Person merging with or into or becoming a subsidiary
of such specified Person.

         "Act", when used with respect to any Holder, has the meaning set forth
in Section 12.3.



                                        1




<PAGE>   9



         "Adjusted Net Assets" of a Guarantor at any date means the amount by
which the fair value of the assets and Property of such Guarantor exceeds the
total amount of liabilities, including, without limitation, contingent
liabilities (after giving effect to all other fixed and contingent liabilities
incurred or assumed on such date), but excluding liabilities under its
Guarantee, of such Guarantor at such date.

         "Affiliate" of any specified Person means another Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For purposes of this definition, "control"
(including, with correlative meanings, the terms "controlling," "controlled by"
and "under common control with"), as used with respect to any Person, shall mean
the possession, directly or indirectly, of the power to direct or cause the
direction of the management or policies of such Person, whether through the
ownership of voting securities, by agreement or otherwise; provided, however,
that beneficial ownership of 10% or more of the Voting Stock of a Person shall
be deemed to be control.

         "Applicable Procedures" means, with respect to any transfer or exchange
of beneficial interests in a Global Note, the rules and procedures of the
Depository that apply to such transfer and exchange.

         "Asset Sale Offer" has the meaning specified in Section 4.7(b).

         "Asset Sale Offer Purchase Date" has the meaning specified in Section
4.7(c).

         "Asset Sale Offer Purchase Price" has the meaning specified in Section
4.7(b).

         "Asset Sale" means any direct or indirect sale, conveyance, transfer,
lease or other disposition (including, without limitation, by way of merger or
consolidation or by means of a Sale and Lease-Back Transaction) by the Company
or any Subsidiary to any Person other than the Company, a Guarantor or a Wholly
Owned Subsidiary, in one transaction, or a series of related transactions, of
(i) any Capital Stock of any Subsidiary (except for directors' qualifying shares
or certain minority interests sold to other Persons solely due to local law
requirements that there be more than one stockholder, but which are not in
excess of what is required for such purpose), or (ii) any other Property or
assets of the Company or any Subsidiary, other than (A) sales of drill-string
components and obsolete or worn out equipment in the ordinary course of business
or other assets that, in the Company's reasonable judgment, are no longer used
or useful in the conduct of the business of the Company and its Subsidiaries),
(B) any drilling contract, charter or other lease of Property or other assets
entered into by the Company or any Subsidiary in the ordinary course of
business, other than any Bargain Purchase Contract, (C) a Restricted Payment or
Restricted Investment permitted under the provisions of Section 4.5 of this
Indenture, (D) a Change of Control, (E) a consolidation, merger, continuance or
the disposition of all or substantially all of the assets of the Company and the
Subsidiaries, taken as a whole, in compliance with the provisions of Section



                                        2




<PAGE>   10



5.1 of this Indenture, (F) any trade or exchange by the Company or any
Subsidiary of one or more drilling rigs for one or more other drilling rigs of
like kind owned or held by another Person, provided that (x) the Fair Value of
the rig or rigs traded or exchanged by the Company or such Subsidiary (including
cash or cash equivalents to be delivered by the Company or such Subsidiary) is
reasonably equivalent to the Fair Value of the drilling rig or rigs (together
with cash or cash equivalents to be received by the Company or such Subsidiary)
or other assets as determined by written appraisal by a nationally (or industry)
recognized investment banking firm or appraisal firm and (y) such exchange is
approved by a majority of the disinterested directors of the Company. An Asset
Sale shall include the requisition of title to, seizure of or forfeiture of any
Property or assets, or any actual or constructive total loss or an agreed or
compromised total loss of any Property or assets.

         "Attributable Indebtedness" in respect of a Sale and Lease-Back
Transaction means, at any date of determination, the present value (discounted
at the interest rate borne by the Senior Notes, compounded annually) of the
total obligations of the lessee for rental payments during the remaining term of
the lease (or to the first date on which the lessee is permitted to terminate
such lease without the payment of a penalty) included in such Sale and
Lease-Back Transaction (including any period for which such lease has been
extended).

         "Average Life" means, as of any date, with respect to any debt
security, the quotient obtained by dividing (i) the sum of the products of (x)
the number of years from such date to the date of each scheduled principal
payment (including any sinking fund or mandatory redemption payment
requirements) of such debt security multiplied in each case by (y) the amount of
such principal payment by (ii) the sum of all such principal payments.

         "Bank Credit Facility" means the $50,000,000 Amended and Restated
Senior Secured Revolving Credit Agreement dated December 31, 1996, as amended
and restated as of April 30, 1997, among the Company and Grey Wolf Drilling
Company, as co-borrowers, Grey Wolf International, Inc. and Murco Drilling
Corporation, as guarantors, the lending institutions party thereto, Bankers
Trust Company, as agent and administrative agent, and ING (US) Capital
Corporation, as co-agent and documentation agent, as from time to time amended.

         "Bargain Purchase Contract" means a drilling contract, charter or lease
that provides for acquisition of Property by the other party to such agreement
during or at the end of the term thereof for less than Fair Market Value thereof
at the time such right to acquire such Property is granted.

         "Board of Directors" means the Board of Directors of the Company or any
Subsidiary, as applicable, or any committee thereof duly authorized to act on
behalf of such Board.

         "Board Resolution" means a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Company or any Subsidiary, as
applicable, to have been duly adopted by the Board



                                        3




<PAGE>   11



of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

         "Business Day" means each Monday, Tuesday, Wednesday, Thursday and
Friday which is not a day on which banking institutions are authorized or
obligated by law or executive order or regulation to close in The City of New
York and Houston, Texas and, with respect to any payment of cash or delivery of
securities, the place of such payment or delivery.

         "Capital Lease Obligation" means, at any time as to any Person with
respect to any Property leased by such Person as lessee, the amount of the
liability with respect to such lease that would be required at such time to be
capitalized and accounted for as a capital lease on the balance sheet of such
Person prepared in accordance with GAAP.

         "Capital Stock" in any Person means any and all shares, interests,
partnership interests, participations or other equivalents in the equity
interest (however designated) in such Person and any rights (other than debt
securities convertible into an equity interest), warrants or options to acquire
any equity interest in such Person.

         "Cash Proceeds" means, with respect to any Asset Sale by any Person,
the aggregate consideration received for such Asset Sale by such Person in the
form of cash or cash equivalents (including any amounts of insurance or other
proceeds received in connection with an Asset Sale of the type described in the
last sentence of the definition thereof), including payments in respect of
deferred payment obligations when received in the form of cash or cash
equivalents (except to the extent that such obligations are financed or sold
with recourse to such Person or any subsidiary thereof).

         "Cedel" means Cedel Bank, societe anonyme.

         "Certificated Senior Notes" means Senior Notes that are substantially
in the form of the Senior Note attached hereto as Exhibit A, that do not include
the information or text called for by footnotes 1, 3 and 4 thereto.

         "Change of Control" means (i) a determination by the Company that any
Person or group (as defined in Section 13(d)(3) or 14(d)(2) of the Exchange Act)
has become the direct or beneficial owner (as defined in Rule 13d-3 under the
Exchange Act) of more than 50% of the Voting Stock of the Company other than
Permitted Holders; (ii) the Company is merged with or into or consolidated with
another corporation and, immediately after giving effect to the merger or
consolidation, less than 50% of the outstanding voting securities entitled to
vote generally in the election of directors or persons who serve similar
functions of the surviving or resulting entity are then beneficially owned
(within the meaning of Rule 13d-3 of the Exchange Act) in the aggregate by (x)
the stockholders of the Company immediately prior to such merger or
consolidation, or (y) if the record



                                        4




<PAGE>   12



date has been set to determine the stockholders of the Company entitled to vote
on such merger or consolidation, the stockholders of the Company as of such a
record date; (iii) the Company, either individually or in conjunction with one
or more Subsidiaries, sells, conveys, transfers or leases, or the Subsidiaries
sell, convey, transfer or lease, all or substantially all of the assets of the
Company or the Company and the Subsidiaries, taken as a whole (either in one
transaction or a series of related transactions), including Capital Stock of the
Subsidiaries, to any Person (other than a Wholly Owned Subsidiary); (iv) the
liquidation or dissolution of the Company; or (v) the first day on which a
majority of the individuals who constitute the Board of Directors of the Company
are not Continuing Directors.

         "Change of Control Offer" has the meaning specified in Section 4.9(a).

         "Change of Control Payment Date" has the meaning specified in Section
4.9(b)(ii).

         "Change of Control Purchase Price" has the meaning specified in Section
4.9(a).

         "Commission" means the United States Securities and Exchange
Commission, as from time to time constituted, created under the Exchange Act, or
if at any time after the execution of this instrument, such Commission is not
existing and performing the duties now assigned to it under the Trust Indenture
Act, then the body performing such duties at such time.

         "Company" means the Person named as the "Company" in the first
paragraph of this Indenture, until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor Person.

         "Consolidated Interest Coverage Ratio" means as of the date of the
transaction giving rise to the need to calculate the Consolidated Interest
Coverage Ratio (the "Transaction Date"), the ratio of (i) the aggregate amount
of EBITDA of the Company and its consolidated Subsidiaries for the four fiscal
quarters for which financial information in respect thereof is available
immediately prior to the applicable Transaction Date (the "Determination
Period") to (ii) the aggregate Consolidated Interest Expense of the Company and
its consolidated Subsidiaries that is anticipated to accrue during a period
consisting of the fiscal quarter in which the Transaction Date occurs and the
three fiscal quarters immediately subsequent thereto (based upon the pro forma
amount and maturity of, and interest payments in respect of, Indebtedness of the
Company and its consolidated Subsidiaries expected by the Company to be
outstanding on the Transaction Date), assuming for the purposes of this
measurement the continuation of market interest rates prevailing on the
Transaction Date and base interest rates in respect of floating interest rate
obligations equal to the base interest rates on such obligations in effect as of
the Transaction Date, provided that if the Company or any of its consolidated
Subsidiaries is a party to any Interest Swap Obligation that would have the
effect of changing the interest rate on any Indebtedness of the Company or any
of its consolidated Subsidiaries for such four-quarter period (or a portion
thereof), the resulting rate shall be used for



                                        5




<PAGE>   13



such four-quarter period or portion thereof; provided, further, that any
Consolidated Interest Expense of the Company with respect to Indebtedness
incurred or retired by the Company or any of its Subsidiaries during the fiscal
quarter in which the Transaction Date occurs shall be calculated as if such debt
was incurred or retired on the first day of the fiscal quarter in which the
Transaction Date occurs; provided, further, that if the transaction giving rise
to the need to calculate the Consolidated Interest Coverage Ratio would have the
effect of increasing or decreasing EBITDA in the future and if such increase or
decrease is readily quantifiable and is attributable to such transaction, EBITDA
shall be calculated on a pro forma basis as if such transaction had occurred on
the first day of the four fiscal quarters referred to in clause (i) of this
definition, and if, during the same four fiscal quarters, (x) the Company or any
of its consolidated Subsidiaries shall have engaged in any Asset Sale, EBITDA
for such period shall be reduced by an amount equal to the EBITDA (if positive),
or increased by an amount equal to the EBITDA (if negative), directly
attributable to the assets which are the subject of such Asset Sale for such
period calculated on a pro forma basis as if such Asset Sale and any related
retirement of Indebtedness had occurred on the first day of such period or (y)
after the Series A Issue Date, the Company or any of its consolidated
Subsidiaries shall have acquired any material assets other than in the ordinary
course of business, EBITDA and Consolidated Interest Expense shall be calculated
on a pro forma basis as if such acquisition had occurred on the first day of
such period.

         "Consolidated Interest Expense" means, with respect to any Person for
any period, without duplication (A) the sum of (i) the aggregate amount of cash
and noncash interest expense (including capitalized interest) of such Person and
its subsidiaries for such period as determined on a consolidated basis in
accordance with GAAP in respect of Indebtedness (including, without limitation,
(v) any amortization of debt discount, (w) net costs associated with Interest
Swap Obligations (including any amortization of discounts), (x) the interest
portion of any deferred payment obligation calculated in accordance with the
effective interest method, (y) all accrued interest and (z) all commissions,
discounts and other fees and charges owed with respect to letters of credit,
bankers acceptances or similar facilities) paid or accrued, or scheduled to be
paid or accrued, during such period; (ii) dividends on Preferred Stock or
Redeemable Stock of such Person (and Preferred Stock or Redeemable Stock of its
subsidiaries if paid to a Person other than such Person or its subsidiaries)
declared and payable in cash; (iii) the portion of any rental obligation of such
Person or its subsidiaries in respect of any Capital Lease Obligation allocable
to interest expense in accordance with GAAP; (iv) the portion of any rental
obligation of such Person or its subsidiaries in respect of any Sale and
Lease-Back Transaction allocable to interest expense (determined as if such were
treated as a Capital Lease Obligation); and (v) to the extent any debt of any
other Person is guaranteed by such Person or any of its subsidiaries, the
aggregate amount of interest paid, accrued or scheduled to be paid or accrued,
by such other Person during such period attributable to any such debt, less (B)
to the extent included in (A) above, amortization or write-off of deferred
financing costs of such Person and its subsidiaries during such period and any
charge related or any premium or penalty paid in connection with redeeming or
retiring any Indebtedness



                                        6




<PAGE>   14



of such Person and its subsidiaries prior to its stated maturity; in the case of
both (A) and (B) above, after elimination of intercompany accounts among such
Person and its subsidiaries and as determined in accordance with GAAP. For
purposes of clause (ii) above, dividend requirements attributable to any
Preferred Stock or Redeemable Stock shall be deemed to be an amount equal to the
amount of dividend requirements on such Preferred Stock or Redeemable Stock
times a fraction, the numerator of which is one, and the denominator of which is
one minus the applicable combined federal, state, local and foreign income tax
rate of the Company and its Subsidiaries (expressed as a decimal), on a
consolidated basis, for the fiscal year immediately preceding the date of the
transaction giving rise to the need to calculate Consolidated Interest Expense.

         "Consolidated Net Income" of any Person means, for any period, the
aggregate net income (or net loss, as the case may be) of such Person and its
subsidiaries for such period on a consolidated basis, determined in accordance
with GAAP, provided that there shall be excluded therefrom, without duplication,
(i) any net income of any Unrestricted Subsidiary, except that the Company's or
any Subsidiary's interest in the net income of such Unrestricted Subsidiary for
such period shall be included in such Consolidated Net Income up to the
aggregate amount of cash or cash equivalents actually distributed by such
Unrestricted Subsidiary during such period to the Company or a Subsidiary as a
dividend or other distribution, (ii) gains and losses, net of taxes, from Asset
Sales or reserves relating thereto, (iii) the net income of any Person that is
not a subsidiary or that is accounted for by the equity method of accounting
which shall be included only to the extent of the amount of dividends or
distributions paid to such Person or its subsidiaries, (iv) items (but not loss
items) classified as extraordinary, unusual or nonrecurring (other than the tax
benefit, if any, of the utilization of net operating loss carryforwards or
alternative minimum tax credits), (v) the net income (but not net loss) of any
Person acquired by such specified Person or any of its subsidiaries in a
pooling-of-interests transaction for any period prior to the date of such
acquisition, (vi) any gain or loss, net of taxes, realized on the termination of
any employee pension benefit plan, (vii) the net income (but not net loss) of
any subsidiary of such specified Person to the extent that the transfer to that
Person of that income is not at the time permitted, directly or indirectly, by
any means (including by dividend, distribution, advance or loan or otherwise),
by operation of the terms of its charter or any agreement with a Person other
than with such specified Person, instrument held by a Person other than by such
specified Person, judgment, decree, order, statute, law, rule or governmental
regulations applicable to such subsidiary or its stockholders, except for any
dividends or distributions actually paid by such subsidiary to such Person, and
(viii) with regard to a non-Wholly Owned Subsidiary, any aggregate net income
(or loss) in excess of such Person's or such subsidiary's pro rata share of such
non-Wholly Owned Subsidiary's net income (or loss).

         "Consolidated Net Worth" of any Person means, as of any date, the sum
of the Capital Stock and additional paid-in capital plus retained earnings (or
minus accumulated deficit) of such Person and its subsidiaries on a consolidated
basis at such date, each item determined in accordance with GAAP, less amounts
attributable to Redeemable Stock of such Person or any of its subsidiaries.



                                        7




<PAGE>   15



         "Continuing Director" means an individual who (i) is a member of the
Board of Directors of the Company and (ii) either (A) was a member of the Board
of Directors of the Company on the Series A Issue Date or (B) whose nomination
for election or election to the Board of Directors of the Company was approved
by vote of at least a majority of the directors then still in office who were
either directors on the Series A Issue Date or whose election or nomination for
election was previously so approved.

         "Corporate Trust Office" means the office of the Trustee at which at
any particular time its corporate trust business shall be principally
administered, which office at the date of execution of this Indenture is located
at 600 Travis Street, Suite 1150, Houston, Texas 77002.

         "Covenant Defeasance" has the meaning specified in Section 9.3.

         "Currency Hedge Obligations" means, at any time as to any Person, the
obligations of such Person at such time which were incurred in the ordinary
course of business pursuant to any foreign currency exchange agreement, option
or future contract or other similar agreement or arrangement designed to protect
against or manage such Person's or any of its subsidiaries' exposure to
fluctuations in foreign currency exchange rates.

         "Default" means any event, act or condition the occurrence of which is,
or after notice or the passage time or both would be, an Event of Default.

         "Defaulted Interest" has the meaning specified in Section 2.12.

         "Defeasance" has the meaning specified in Section 9.2.

         "Depositary" means The Depository Trust Company, its nominees and their
respective successors.

         "Depositary" means, with respect to the Senior Notes issuable or issued
in whole or in part in global form, the Person specified in Section 2.3 hereof
as the Depositary with respect to the Senior Notes, until a successor shall have
been appointed and become such Depositary pursuant to the applicable provision
of this Indenture, and, thereafter, "Depositary" shall mean or include such
successor.

         "Determination Period" has the meaning specified under clause (i) of
the definition of "Consolidated Interest Coverage Ratio."

         "DTC" has the meaning specified in Section 2.3.

         "EBITDA" means, with respect to any Person for any period, the
Consolidated Net Income of such Person for such period, plus to the extent
reflected in the income statement of such Person



                                        8




<PAGE>   16



for such period from which Consolidated Net Income is determined, without
duplication, (i) Consolidated Interest Expense, (ii) income tax expense, (iii)
depreciation expense, (iv) amortization expense, (v) any charge related to any
premium or penalty paid in connection with redeeming or retiring any
Indebtedness prior to its stated maturity, (vi) any other non-cash charges and
(vii) to the extent not otherwise covered by the adjustments contained in the
proviso to this definition, non-recurring charges of approximately $6.1 million
incurred during 1996 in employment severance costs, exit costs attributable to
its exiting Argentina and Mexico and other non-recurring charges, all as
described in the Company's Form 10-K for the year ended December 31, 1996 and
minus, to the extent reflected in such income statement, any noncash credits
that had the effect of increasing Consolidated Net Income of such Person for
such period; provided that for purposes of determining EBITDA with respect to
the Company, Consolidated Net Income shall exclude any net income or loss for
the year ended December 31, 1996 associated with the Company's Argentine or
Mexican divisions.

         "Euroclear" means the Euroclear System for which Morgan Guaranty Trust
Company of New York, Brussels office, is the operator and depositary.

         "Event of Default" has the meaning specified in Section 6.1.

         "Excess Proceeds" has the meaning specified in Section 4.7(b).

         "Exchange Act" means the Securities and Exchange Act of 1934, as
amended.

         "Exchange Global Note" means one or more Global Notes that do not and
are not required to bear the Private Placement Legend.

         "Exchange Notes" has the meaning set forth in the Recitals to this
Indenture and more particularly means any of the Senior Notes authenticated and
delivered under this Indenture pursuant to the Exchange Offer.

         "Exchange Offer Registration Statement" has the meaning set forth in
the Registration Rights Agreement.

         "Exchange Offer" means the offer that may be made by the Company
pursuant to the Registration Rights Agreement to exchange Exchange Notes for
Initial Senior Notes.

         "Fair Market Value" means, with respect to consideration received or to
be received pursuant to any transaction by any Person, the fair market value of
such consideration as determined in good faith by the Board of Directors of the
Company.

         "Fair Value" means, with respect to any asset or Property, the price
which could be negotiated in an arm's-length free market transaction, for cash,
between a willing seller and a willing



                                        9




<PAGE>   17



buyer, neither of whom is under undue pressure or compulsion to complete the
transaction.

         "GAAP" means, at any date, United States generally accepted accounting
principles, consistently applied, as set forth in the opinions of the Accounting
Principles Board of the American Institute of Certified Public Accountants
("AICPA") and statements of the Financial Accounting Standards Board, or in such
other statements by such other entity as may be designated by the AICPA, that
are applicable to the circumstances as of the date of determination; provided,
however, that all calculations made for purposes of determining compliance with
the provisions set forth in this Indenture shall utilize GAAP in effect at the
Series A Issue Date.

         "Global Note" or "Global Senior Note" means, individually and
collectively, the Regulation S Global Notes, the U.S. Global Notes and the
Exchange Global Note.

         "Grey Wolf Acquisition" means the agreement to merge Grey Wolf into
Drillers, Inc. pursuant to an Agreement and Plan of Merger dated March 7, 1997,
by and among the Company, Drillers, Inc. and Grey Wolf, as such may be amended
to the Issue Date.

         "Grey Wolf" means Grey Wolf Drilling Company, a Texas corporation.

         "Guarantee" means an unconditional guaranty of the Senior Notes given
by any Subsidiary pursuant to the provisions of Article 11 of this Indenture.

         "Guarantor" means Grey Wolf Drilling Company, Grey Wolf International,
Inc., Murco Drilling Corporation and DI Energy Inc., each a Texas corporation
and a Subsidiary, and each other Subsidiary of the Company that is required to
guarantee the Company's Obligations under the Senior Notes and this Indenture
pursuant to the provisions of Article 11 of this Indenture and any other
Subsidiary of the Company that executes a supplemental indenture in which such
Subsidiary agrees to guarantee the Company's Obligations under the Senior Notes
and this Indenture.

         "Holder" means the Person in whose name a Senior Note is registered on
the Registrar's books.

         "incur" means, with respect to any Indebtedness or other obligation of
any Person, to create, issue, suffer to exist, incur (by conversion, exchange or
otherwise), assume, guarantee or otherwise become liable in respect of such
Indebtedness or other obligation or the recording, as required pursuant to GAAP
or otherwise, of any such Indebtedness or obligation on the balance sheet of
such Person (and "incurrence," "incurred," "incurrable" and "incurring" shall
have meanings correlative to the foregoing); provided that a change in GAAP that
results in an obligation of such Person that exists at such time becoming
Indebtedness shall not be deemed an incurrence of such Indebtedness.
Indebtedness otherwise incurred by a Person before it becomes a Subsidiary shall
be deemed to have been incurred at the time at which it becomes a Subsidiary.



                                       10




<PAGE>   18



         "Indebtedness" as applied to any Person means, at any time, without
duplication, whether recourse is to all or a portion of the assets of such
Person, and whether or not contingent, (i) any obligation of such Person for
borrowed money; (ii) any obligation of such Person evidenced by bonds,
debentures, notes or other similar instruments, including, without limitation,
any such obligations incurred in connection with acquisition of Property, assets
or businesses, excluding accounts payable made in the ordinary course of
business which are not more than 90 days overdue or which are being contested in
good faith and by appropriate proceedings; (iii) any obligation of such Person
for all or any part of the purchase price of Property or for the cost of
Property constructed or of improvements thereto (including any obligation under
or in connection with any letter of credit related thereto), other than accounts
payable incurred in respect of Property and services purchased in the ordinary
course of business which are no more than 90 days overdue or which are being
contested in good faith and by appropriate proceedings; (iv) any obligation of
such Person upon which interest charges are customarily paid (other than
accounts payable incurred in the ordinary course of business); (v) any
obligation of such Person under conditional sale or other title retention
agreements relating to purchased Property; (vi) any obligation of such Person
issued or assumed as the deferred purchase price of Property (other than
accounts payable incurred in the ordinary course of business which are no more
than 90 days overdue or which are being contested in good faith and by
appropriate proceedings); (vii) any Capital Lease Obligation or Attributable
Indebtedness pursuant to any Sale and Lease-Back Transaction of such Person;
(viii) any obligation of any other Person secured by (or for which the obligee
thereof has an existing right, contingent or otherwise, to be secured by) any
Lien on Property owned or acquired, whether or not any obligation secured
thereby has been assumed, by such Person; (ix) any obligation of such Person in
respect of any letter of credit supporting any obligation of any other Person;
(x) the maximum fixed repurchase price of any Redeemable Stock of such Person
(or if such Person is a subsidiary, any Preferred Stock of such Person); (xi)
the notional amount of any Interest Swap Obligation or Currency Hedge Obligation
of such Person at the time of determination; and (xii) any obligation which is
in economic effect a guarantee, regardless of its characterization (other than
an endorsement in the ordinary course of business), with respect to any
Indebtedness of another Person, to the extent guaranteed. For purposes of the
preceding sentence, the maximum fixed repurchase price of any Redeemable Stock
or subsidiary Preferred Stock that does not have a fixed repurchase price shall
be calculated in accordance with the terms of such Redeemable Stock or
subsidiary Preferred Stock as if such Redeemable Stock or subsidiary Preferred
Stock were repurchased on any date on which Indebtedness shall be required to be
determined pursuant to the Indenture; provided, however, that if such Redeemable
Stock or subsidiary Preferred Stock is not then permitted to be repurchased, the
repurchase price shall be the book value of such Redeemable Stock or subsidiary
Preferred Stock. The amount of Indebtedness of any Person at any date shall be
the outstanding balance at such date of all unconditional obligations as
described above and the maximum liability of any guarantees at such date;
provided that for purposes of calculating the amount of any non-interest bearing
or other discount security, such Indebtedness shall be deemed to be the
principal amount thereof that would be shown on the balance sheet of the issuer
dated such date prepared in accordance with GAAP but



                                       11




<PAGE>   19



that such security shall be deemed to have been incurred only on the date of the
original issuance thereof.

         "Indenture" means this Indenture as originally executed or as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into pursuant to the applicable provisions hereof,
including, for all purposes of this Indenture and any such supplemental
indenture, the provisions of the Trust Indenture Act that are deemed to be a
part of and govern this Indenture, and any such supplemental indenture,
respectively.

         "Indirect Participant" means a Person who holds an interest through a
Participant.

         "Indrillers" means INDRILLERS, L.L.C., a Michigan limited liability
company.

         "Initial Senior Notes" has the meaning set forth in the Recitals to
this Indenture and more particularly means any of the Senior Notes authenticated
and delivered under this Indenture other than Exchange Notes.

          "Interest Payment Date" means the Stated Maturity of an installment of
interest on the Senior Notes, which date shall be January 1 and July 1 of each
year, commencing July 1, 1998.

         "Interest Swap Obligation" means, with respect to any Person, the
obligation of such Person pursuant to any interest rate swap agreement, interest
rate cap, collar or floor agreement or other similar agreement or arrangement
designed to protect against or manage such Person's or any of its subsidiaries'
exposure to fluctuations in interest rates.

         "Investment" means, with respect to any Person, any direct, indirect or
contingent investment in another Person, whether by means of a share purchase,
capital contribution, loan, advance (other than advances to employees for moving
and travel expenses, drawing accounts and similar expenditures in the ordinary
course of business) or similar credit extension constituting Indebtedness of
such other Person, and any guarantee of Indebtedness of any other Person;
provided that the term "Investment" shall not include any transaction involving
the purchase or other acquisition (including by way of merger) of Property
(including Capital Stock) by the Company or any Subsidiary in exchange for
Capital Stock (other than Redeemable Stock) of the Company. The amount of any
Person's Investment shall be the original cost of such Investment to such
Person, plus the cost of all additions thereto paid by such Person, and minus
the amount of any portion of such Investment repaid to such Person in cash as a
repayment of principal or a return of capital, as the case may be, but without
any other adjustments for increases or decreases in value, or write-ups,
writedowns, or write-offs with respect to such Investment. In determining the
amount of any Investment involving a transfer of any Property or assets other
than cash, such Property or assets shall be valued at its Fair Value at the time
of such transfer as determined in good faith by the board of directors (or
comparable body) of the Person making such transfer. The Company shall be deemed
to make an



                                       12




<PAGE>   20



"Investment" in the amount of the Fair Value of the Assets of a Subsidiary at
the time such Subsidiary is designated an Unrestricted Subsidiary.

         "Issue Date" means the date on which the Senior Notes are first
authenticated and delivered under this Indenture.

         "Joint Venture" means any Person (other than a Guarantor) designated as
such by a Board Resolution of the Company and as to which (i) the Company, any
Guarantor or any Joint Venture owns less than 50% of the Capital Stock of such
Person; (ii) no more than 10 unaffiliated Persons own of record any Capital
Stock of such Person; (iii) at all times, each such Person owns the same
proportion of each class of Capital Stock of such Person outstanding at such
time; (iv) no Indebtedness of such Person is or becomes outstanding other than
Non-Recourse Indebtedness; (v) there exist no consensual encumbrances or
restrictions on the ability of such Person to (x) pay, directly or indirectly,
dividends or make any other distributions in respect of its Capital Stock to the
holders of its Capital Stock or (y) pay any Indebtedness or other obligation
owed to the holders of its Capital Stock or (z) make any Investment in the
holders of its Capital Stock, in each case other than the types of consensual
encumbrances or restrictions that would be permitted under the provisions of
Section 4.6 of this Indenture if such Person were a Subsidiary; and (vi) the
business engaged in by such Person is a Related Business.

         "Lien" means any mortgage, pledge, hypothecation, charge, assignment,
deposit arrangement, encumbrance, security interest, lien (statutory or other),
or preference, priority or other security or similar agreement or preferential
arrangement of any kind or nature whatsoever (including, without limitation, any
agreement to give or grant a Lien or any lease, conditional sale or other title
retention agreement having substantially the same economic effect as any of the
foregoing).

         "Maturity" means the date on which the principal of a Senior Note
becomes due and payable as provided therein or in this Indenture, whether at the
Stated Maturity or the Change of Control Payment Date or purchase date
established pursuant to the terms of this Indenture for an Asset Sale Offer or
by declaration of acceleration, call for redemption or otherwise.

         "Moody's" means Moody's Investors Service, Inc., or, if Moody's
Investors Service, Inc. shall cease rating the specified debt securities and
such ratings business with respect thereto shall have been transferred to a
successor Person, such successor person; provided that if Moody's Investors
Service, Inc. ceases rating the specified debt securities and its ratings
business with respect thereto shall not have been transferred to any successor
Person or such successor Person is S&P, then "Moody's" shall mean any other
nationally recognized rating agency (other than S&P) that rates the specified
debt securities selected in good faith by the Board of Directors of the Company
in a Board Resolution.



                                       13




<PAGE>   21



         "Net Available Proceeds" means, (a) as to any Asset Sale (other than a
Bargain Purchase Contract), the Cash Proceeds therefrom, net of all legal and
title expenses, commissions and other fees and expenses incurred, and all
Federal, state, foreign, recording and local taxes payable as a consequence of
such Asset Sale, net of all payments made to any Person other than the Company
or a Subsidiary on any Indebtedness which is secured by such assets, in
accordance with the terms of any Lien upon or with respect to such assets, or
which must by its terms, or in order to obtain a necessary consent to such Asset
Sale, or by applicable law, be repaid out of the proceeds from such Asset Sale
and, as for any Asset Sale by a Subsidiary, net of the equity interest in such
Cash Proceeds of any holder of Capital Stock of such Subsidiary (other than the
Company, any other Subsidiary or any Affiliate of the Company or any such other
Subsidiary) and (b) as to any Bargain Purchase Contract, an amount equal to (i)
that portion of the rental or other payment stream arising under a Bargain
Purchase Contract that represents an amount in excess of the Fair Market Value
of the rental or other payments with respect to the pertinent Property or other
asset and (ii) the Cash Proceeds from the sale of such Property or other asset,
net of the amount set forth in clause (a) above, in each case as and when
received.

         "Non-Recourse Indebtedness" means Indebtedness or that portion of
Indebtedness of an Unrestricted Subsidiary or a foreign Subsidiary not
constituting a Guarantor as to which (a) neither the Company nor any other
Subsidiary (other than an Unrestricted Subsidiary or a Subsidiary of such
foreign Subsidiary) (i) provides credit support including any undertaking,
agreement or instrument which would constitute Indebtedness or (ii) is directly
or indirectly liable for such Indebtedness and (b) no default with respect to
such Indebtedness (including any rights which the holders thereof may have to
take enforcement action against an Unrestricted Subsidiary or such foreign
Subsidiary) would permit (upon notice, lapse of time or both) any holder of any
other Indebtedness of the Company or its other Subsidiaries to declare a default
on such other Indebtedness or cause the payment thereof to be accelerated or
payable prior to its stated maturity.

         "Obligations" means, with respect to any Indebtedness, any obligation
thereunder, including, without limitation, principal, premium and interest
(including post petition interest thereon), penalties, fees, costs, expenses,
indemnifications, reimbursements, damages and other liabilities.

         "Obligors" means the Company and the Guarantors, collectively;
"Obligor" means the Company or any Guarantor.

         "Offering Memorandum" means the Offering Memorandum, dated May 5, 1998,
relating to the Company's offering and placement of the Initial Senior Notes.

         "Officers' Certificate" means a certificate signed by the Chairman of
the Board, a Vice Chairman of the Board, the President, the Chief Executive
Officer, the Chief Operating Officer or a Vice President, and by the Chief
Financial Officer, the Chief Accounting Officer, the Treasurer, an Assistant
Treasurer, the Secretary or an Assistant Secretary of the Company or a
Subsidiary (each,



                                       14




<PAGE>   22



an "Officer") and delivered to the Trustee, which shall comply with this
Indenture.

         "Opinion of Counsel" means a written opinion from legal counsel who is
acceptable to the Trustee. The counsel may be an employee of or counsel to the
Company, a Guarantor or the Trustee.

         "Order" means a written order signed in the name of the Company by an
officer and delivered to the Trustee.

         "Participant" means, with respect to DTC, Euroclear or Cedel, a Person
who has an account with DTC, Euroclear or Cedel, respectively (and, with respect
to DTC, shall include Euroclear and Cedel).

         "Paying Agent" has the meaning specified in Section 2.3.

         "Permitted Holders" means Norex Industries, Inc., Somerset Capital
Partners, Mike L. Mullen and Roy T. Oliver, Jr. and their respective Affiliates.

         "Permitted Indebtedness" means (a) Indebtedness of the Company under
the Senior Notes and the Series A Notes; (b) Indebtedness (and any guarantee
thereof) under one or more credit or revolving credit facilities with a bank or
syndicate of banks or financial institutions or other lenders, including,
without limitation, the Bank Credit Facility, as such may be amended, modified,
revised, extended, replaced, or refunded from time to time, in an aggregate
principal amount at any one time outstanding not to exceed $100,000,000, less
any amounts derived from Asset Sales and applied to the required permanent
reduction of Senior Debt (and a permanent reduction of the related commitment to
lend or amount available to be reborrowed in the case of a revolving credit
facility) under such credit facilities as contemplated by the provisions of
Section 4.7 of this Indenture (provided that the aggregate principal amount of
Indebtedness deemed to be incurred under this clause (b) shall be the same
amount as is deemed incurred under clause (b) of the definition of the term
"Permitted Indebtedness" in the Series A Indenture); (c) Indebtedness of the
Company or any Subsidiary under Interest Swap Obligations, provided that (i)
such Interest Swap Obligations are related to payment obligations on
Indebtedness otherwise permitted under the provisions of Section 4.3 of this
Indenture and (ii) the notional principal amount of such Interest Swap
Obligations does not exceed the principal amount of the Indebtedness to which
such Interest Swap Obligations relate; (d) Indebtedness of the Company or any
Subsidiary under Currency Hedge Obligations, provided that (i) such Currency
Hedge Obligations are related to payment obligations on Indebtedness otherwise
permitted under the provisions of Section 4.3 of this Indenture or to the
foreign currency cash flows reasonably expected to be generated by the Company
and the Subsidiaries and (ii) the notional principal amount of such Currency
Hedge Obligations does not exceed the principal amount of the Indebtedness and
the amount of the foreign currency cash flows to which such Currency Hedge
Obligations relate; (e) Indebtedness of the Company or any Subsidiary
outstanding on the Series A Issue Date and listed on a schedule attached to the
Series A



                                       15




<PAGE>   23



Indenture; (f) (1)the Guarantees of the Senior Notes and the Series A Notes (and
any assumption of the Obligations guaranteed thereby) and (2) Indebtedness of a
Guarantor constituting a guarantee of Indebtedness of the Company incurred in
compliance with Section 4.3 of this Indenture (and any assumption of the
Obligations guaranteed thereby); (g) Indebtedness of the Company or any
Subsidiary in respect of bid performance bonds, surety bonds, appeal bonds and
letters of credit or similar arrangements issued for the account of the Company
or any Subsidiary, in each case in the ordinary course of business and other
than for an obligation for money borrowed; (h) Indebtedness of the Company to a
Guarantor or other Wholly Owned Subsidiary and Indebtedness of a Guarantor or
other Wholly Owned Subsidiary to the Company or another Guarantor or other
Wholly Owned Subsidiary; provided that upon any subsequent issuance or transfer
of any Capital Stock or any other event which results in any such Guarantor
ceasing to be a Guarantor or such Wholly Owned Subsidiary ceasing to be a Wholly
Owned Subsidiary, as the case may be, or any other subsequent transfer of any
such Indebtedness (except to the Company or a Guarantor or other Wholly Owned
Subsidiary), such Indebtedness shall be deemed, in each case, to be incurred and
shall be treated as an incurrence for purposes of Section 4.3 of this Indenture
at the time the Guarantor in question ceased to be a Guarantor or the Wholly
Owned Subsidiary in question ceased to be a Wholly Owned Subsidiary; (i)
Subordinated Indebtedness of the Company to an Unrestricted Subsidiary for money
borrowed; (j) Indebtedness of the Company in connection with a purchase of the
Senior Notes and the Series A Notes pursuant to a Change of Control Offer under
this Indenture and the Series A Indenture, provided that the aggregate principal
amount of such Indebtedness does not exceed 101% of the aggregate principal
amount at Stated Maturity of the Senior Notes and the Series A Notes purchased
pursuant to such Change of Control Offer; provided, further, that such
Indebtedness (A) has an Average Life equal to or greater than the remaining
Average Life of the Senior Notes and the Series A Notes and (B) does not mature
prior to one year following the Stated Maturity of the Senior Notes and the
Series A Notes; (k) Permitted Refinancing Indebtedness; (l) Permitted Subsidiary
Refinancing Indebtedness; and (m) additional Indebtedness incurred after the
Series A Issue Date in an aggregate principal amount not in excess of $2,500,000
at any one time outstanding (provided that the aggregate principal amount of
Indebtedness deemed to be incurred under this clause (m) shall be the same
amount as is deemed incurred under clause (m) of the definition of the term
"Permitted Indebtedness" in the Series A Indenture). So as to avoid duplication
in determining the amount of Permitted Indebtedness under any clause of this
definition, guarantees permitted to be incurred pursuant to this Indenture of,
or Obligations permitted to be incurred pursuant to this Indenture in respect of
letters of credit supporting, Indebtedness otherwise included in the
determination of such amount shall not also be included.

         "Permitted Investments" means (a) certificates of deposit, bankers
acceptances, time deposits, Eurocurrency deposits and similar types of
Investments routinely offered by a commercial bank organized in the United
States with final maturities of one year or less issued by commercial banks
organized in the United States having capital and surplus in excess of
$300,000,000; (b) commercial paper issued by any corporation, if such commercial
paper has credit ratings of at least "A-1" or its



                                       16




<PAGE>   24



equivalent by S&P and at least "P-I" or its equivalent by Moody's; (c) U.S.
Government Obligations with a maturity of four years or less; (d) repurchase
obligations for instruments of the type described in clause (c) with any bank
meeting the qualifications specified in clause (a) above; (e) shares of money
market mutual or similar funds having assets in excess of $100,000,000; (f)
payroll advances in the ordinary course of business; (g) other advances and
loans to officers and employees of the Company or any Subsidiary, so long as the
aggregate principal amount of such advances and loans does not exceed $500,000
at any one time outstanding; (h) Investments represented by that portion of the
proceeds from Asset Sales that is not required to be Cash Proceeds by Section
4.7 of this Indenture; (i) Investments made by the Company in Guarantors or in
its other Wholly Owned Subsidiaries (or any Person that will be a Wholly Owned
Subsidiary as a result of such Investment) or by a Subsidiary in the Company or
in one or more Guarantors or other Wholly Owned Subsidiaries (or any Person that
will be a Wholly Owned Subsidiary as a result of such Investment); (j)
Investments in stock, obligations or securities received in settlement of debts
owing to the Company or any Subsidiary as a result of bankruptcy or insolvency
proceedings or upon the foreclosure, perfection or enforcement of any Lien in
favor of the Company or any Subsidiary, in each case as to debt owing to the
Company or any Subsidiary that arose in the ordinary course of business of the
Company or any such Subsidiary; (k) certificates of deposit, bankers
acceptances, time deposits, Eurocurrency deposits and similar types of
Investments routinely offered by a commercial bank organized in the United
States with final maturities of one year or less and in an aggregate amount not
to exceed $5,000,000 at any one time outstanding with a commercial bank
organized in the United States having capital and surplus in excess of
$75,000,000; (l) Venezuelan and other foreign bank deposits and cash equivalents
in jurisdictions where the Company or its Subsidiaries are then actively
conducting business; (m) Investments in Grey Wolf pursuant to the Grey Wolf
Acquisition agreement; (n) Interest Swap Obligations with respect to any
floating rate Indebtedness that is permitted by the terms of this Indenture to
be outstanding; (o) Currency Hedge Obligations, provided that such Currency
Hedge Obligations constitute Permitted Indebtedness permitted by clause (d) of
the definition thereof; (p) Investments in prepaid expenses, negotiable
instruments held for collection and lease, utility, worker's compensation and
performance and other similar deposits in the ordinary course of business; and
(q) Investments pursuant to any agreement or obligation of the Company or any
Subsidiary in effect on the Series A Issue Date and listed on a schedule
attached to the Series A Indenture.

         "Permitted Liens" means (a) Liens in existence on the Series A Issue
Date; (b) Liens created for the benefit of the Senior Notes, the Guarantees, the
Series A Notes and/or any guarantees thereof; (c) Liens on Property of a Person
existing at the time such Person is merged or consolidated with or into the
Company or a Subsidiary (and not incurred as a result of, or in anticipation of,
such transaction), provided that any such Lien relates solely to such Property;
(d) Liens on Property existing at the time of the acquisition thereof (and not
incurred as a result of, or in anticipation of such transaction), provided that
any such Lien relates solely to such Property; (e) Liens incurred or pledges and
deposits made in connection with worker's compensation, unemployment insurance
and



                                       17




<PAGE>   25



other social security benefits, statutory obligations, bid, surety or appeal
bonds, performance bonds or other obligations of a like nature incurred in the
ordinary course of business; (f) Liens imposed by law or arising by operation of
law, including without limitation, landlords', mechanics', carriers',
warehousemen's, materialmen's, suppliers' and vendors Liens and Liens for
master's and crew's wages and other similar maritime Liens, and incurred in the
ordinary course of business for sums not delinquent or being contested in good
faith, if such reserves or other appropriate provisions, if any, as shall be
required by GAAP shall have been made with respect thereof; (g) zoning
restrictions, easements, licenses, covenants, reservations, restrictions on the
use of real property and defects, irregularities and deficiencies in title to
real property that do not, individually or in the aggregate, materially affect
the ability of the Company or any Subsidiary to conduct its business presently
conducted; (h) Liens for taxes or assessments or other governmental charges or
levies not yet due and payable, or the validity of which is being contested by
the Company or a Subsidiary in good faith and by appropriate proceedings upon
stay of execution or the enforcement thereof and for which adequate reserves in
accordance with GAAP or other appropriate provision has been made; (i) Liens to
secure Indebtedness incurred for the purpose of financing all or a part of the
purchase price or construction cost of Property acquired or constructed after
the Series A Issue Date, provided that (l) the principal amount of Indebtedness
secured by such Liens shall not exceed 100% of the lesser of cost or Fair Market
Value of the Property so acquired, upgraded or constructed plus transaction
costs related thereto, (2) such Liens shall not encumber any other assets or
Property of the Company or any Subsidiary (other than the proceeds thereof and
accessions and upgrades thereto) and (3) such Liens shall attach to such
Property within 120 days of the date of the completion of the construction or
acquisition of such Property; (j) Liens securing Capital Lease Obligations,
provided, further, that such Liens secure Capital Lease Obligations which, when
combined with (l) the outstanding secured Indebtedness of the Company and its
Subsidiaries (other than Indebtedness secured by Liens described under clauses
(b) and (i) hereof) and (2) the aggregate principal amount of all other Capital
Lease Obligations of the Company and Subsidiaries, does not exceed $5,000,000 at
any one time outstanding; (k) Liens to secure any extension, renewal,
refinancing or refunding (or successive extensions, renewals, refinancings or
refundings), in whole or in part, of any Indebtedness secured by Liens referred
to in the foregoing clauses (a), (c) and (d), provided, further, that such Lien
does not extend to any other Property of the Company or any Subsidiary and the
principal amount of the Indebtedness secured by such Lien is not increased; (l)
any charter or lease; (m) leases or subleases of real property to other Persons;
(n) Liens securing Permitted Indebtedness described in clause (b) of the
definition thereof; (o) judgment liens not giving rise to an Event of Default so
long as any appropriate legal proceedings which may have been initiated for the
review of such judgment shall not have been finally terminated or the period
within which such proceeding may be initiated shall not have expired; (p) rights
of off-set of banks and other Persons; and (q) liens in favor of the Company.

         "Permitted Refinancing Indebtedness" means Indebtedness of the Company,
incurred in exchange for, or the net proceeds of which are used to renew,
extend, refinance, refund or



                                       18




<PAGE>   26



repurchase, outstanding Indebtedness of the Company which outstanding
Indebtedness was incurred in accordance with, or is otherwise permitted by, the
terms of clauses (a) and (e) of the definition of "Permitted Indebtedness,"
provided that (i) if the Indebtedness being renewed, extended, refinanced,
refunded or repurchased is pari passu with or subordinated in right of payment
(without regard to its being secured) to the Senior Notes, then such new
Indebtedness is pari passu with or subordinated in right of payment (without
regard to its being secured) to, as the case may be, the Senior Notes at least
to the same extent as the Indebtedness being renewed, extended, refinanced,
refunded or repurchased, (ii) such new Indebtedness is scheduled to mature later
than the Indebtedness being renewed, extended, refinanced, refunded or
repurchased, (iii) such new Indebtedness has an Average Life at the time such
Indebtedness is incurred that is greater than the Average Life of the
Indebtedness being renewed, extended, refinanced, refunded or repurchased, and
(iv) such new Indebtedness is in aggregate principal amount (or, if such
Indebtedness is issued at a price less than the principal amount thereof, the
aggregate amount of gross proceeds therefrom is) not in excess of the aggregate
principal amount then outstanding of the Indebtedness being renewed, extended,
refinanced, refunded or repurchased (or if the Indebtedness being renewed,
extended, refinanced, refunded or repurchased was issued at a price less than
the principal amount thereof, then not in excess of the amount of liability in
respect thereof determined in accordance with GAAP) plus the amount of
reasonable fees, expenses and premium, if any, incurred by the Company or such
Subsidiary in connection therewith.

         "Permitted Subsidiary Refinancing Indebtedness" means Indebtedness of
any Subsidiary, incurred in exchange for, or the net proceeds of which are used
to renew, extend, refinance, refund or repurchase, outstanding Indebtedness of
such Subsidiary which outstanding Indebtedness was incurred in accordance with,
or is otherwise permitted by, the terms of clauses (e) and (f) of the definition
of "Permitted Indebtedness," provided that (i) if the Indebtedness being
renewed, extended, refinanced, refunded or repurchased is pari passu with or
subordinated in right of payment (without regard to its being secured) to the
Guarantee of such Subsidiary, then such new Indebtedness is pari passu with or
subordinated in right of payment (without regard to its being secured) to, as
the case may be, the Guarantee of such Subsidiary at least to the same extent as
the Indebtedness being renewed, extended, refinanced refunded or repurchased,
(ii) such new Indebtedness is scheduled to mature later than the Indebtedness
being renewed, extended, refinanced, refunded or repurchased, (iii) such new
Indebtedness has an Average Life at the time such Indebtedness is incurred that
is greater than the Average Life of the Indebtedness being renewed, extended,
refinanced, refunded or repurchased, and (iv) such new Indebtedness is in an
aggregate principal amount (or, if such Indebtedness is issued at a price less
than the principal amount thereof, the aggregate amount of gross proceeds
therefrom is) not in excess of the aggregate principal amount then outstanding
of the Indebtedness being renewed, extended, refinanced, refunded or repurchased
(or if the Indebtedness being renewed, extended, refinanced, refunded or
repurchased was issued at a price less than the principal amount thereof, then
not in excess of the amount of liability in respect thereof determined in
accordance with GAAP) plus the amount of reasonable fees, expenses and



                                       19




<PAGE>   27



premium, if any, incurred by the Company or such Subsidiary in connection
therewith.

         "Person" means any individual, corporation, partnership, joint venture,
incorporated or unincorporated association, joint stock company, trust,
unincorporated organization or government or other agency or political
subdivision thereof or other entity of any kind.

         "Preferred Stock" of any Person means Capital Stock of such Person of
any class or classes (however designated) that ranks prior, as to the payment of
dividends and/or as to the distribution of assets upon any voluntary or
involuntary liquidation, dissolution or winding up of such Person, to shares of
Capital Stock of at least one other class of such Person.

         "Private Placement Layered" has the meaning specified in Section
2.6(e)(i).

         "Proceeding" has the meaning specified in Section 12.11(a).

         "Process Agent" has the meaning specified in Section 12.11(a).

         "Property" means, with respect to any Person, any interest of such
Person in any kind of property or asset, whether real, personal or mixed, or
tangible or intangible, excluding Capital Stock in any other Person.

         "Qualified Equity Offering" means an offering made after the Series A
Issue Date of Capital Stock (other than Redeemable Stock) of the Company for
cash, whether pursuant to an effective registration statement under the
Securities Act or pursuant to an available exemption from registration under the
Securities Act.

         "Qualified Institutional Buyer" or "QIB" shall have the meaning
specified in Rule 144A under the Securities Act.

         "Record Date" means, for the interest payable on any Interest Payment
Date, the date specified in Section 2.12.

         "Redeemable Stock" means, with respect to any Person, any equity
security that by its terms or otherwise is required to be redeemed, or is
redeemable at the option of the holder thereof, at any time prior to one year
following the Stated Maturity of the Senior Notes or is exchangeable into
Indebtedness of such Person or any of its subsidiaries.

         "Redemption Date" means, when used with respect to any Senior Note or
part thereof to be redeemed hereunder, the date fixed for redemption of such
Senior Notes pursuant to the terms of the Senior Notes and this Indenture.

         "Redemption Price" means, when used with respect to any Senior Note or
part thereof to be



                                       20




<PAGE>   28



redeemed hereunder, the price fixed for redemption of such Senior Note pursuant
to the terms of the Senior Notes and this Indenture, plus accrued and unpaid
interest thereon, if any to the Redemption Date.

         "Registrar" has the meaning specified in Section 2.3.

         "Registration Rights Agreement" means the Registration Rights
Agreement, dated as of the date of this Indenture, by and among the Company and
Initial Purchasers, as such agreement may be amended, modified or supplemented
from time to time.

         "Regulation S Global Note" means a permanent global senior note that
contains the text referred to in footnotes 1 and 3 and the additional schedule
referred to in footnote 4 to the form of the Senior Note attached hereto as
Exhibit A, and that is deposited with the Senior Note Custodian and registered
in the name of the Depository or its nominee, representing the Initial Senior
Notes sold in reliance on Regulation S.

         "Regulation S" means Regulation S under the Securities Act (including
any successor regulation thereto), as it may be amended from time to time.

         "Related Business" means the land drilling business and activities
incidental thereto and any business related or ancillary thereto.

         "Replacement Asset" means a Property or asset that, as determined by
the Board of Directors of the Company as evidenced by a Board Resolution, is
used or is useful in a Related Business.

         "Responsible Officer" means, when used with respect to the Trustee, any
officer assigned to the Corporate Trust Office, including any vice president,
assistant vice president, assistant secretary or any other officer of the
Trustee to whom any corporate trust matter is referred because of his or her
knowledge of and familiarity with the particular subject.

         "Restricted Investment" means any Investment in any Person, including
an Unrestricted Subsidiary or the designation of a Subsidiary as an Unrestricted
Subsidiary, other than a Permitted Investment.

         "Restricted Payment" means to (i) declare or pay any dividend on, or
make any distribution in respect of, or purchase, redeem, retire or otherwise
acquire for value, any Capital Stock of the Company or any Affiliate of the
Company, or warrants, rights or options to acquire such Capital Stock, other
than (x) dividends payable solely in the Capital Stock (other than Redeemable
Stock) of the Company or such Affiliate, as the case may be, or in warrants,
rights or options to acquire such Capital Stock and (y) dividends or
distributions by a Subsidiary to the Company or to a Wholly Owned Subsidiary;
(ii) make any principal payment on, or redeem, repurchase, defease (including



                                       21




<PAGE>   29



an in-substance or legal defeasance) or otherwise acquire or retire for value
(including pursuant to mandatory repurchase covenants), prior to any scheduled
principal payment, scheduled sinking fund payment or other stated maturity,
Indebtedness of the Company or any Subsidiary which is subordinated (whether
pursuant to its terms or by operation of law) in right of payment to the Senior
Notes or the Guarantees, as applicable; or (iii) make any Restricted Investment
in any Person.

         "Retired Indebtedness or Stock" has the meaning specified in Section
4.4.

         "Rule 144A" means Rule 144A under the Securities Act (including any
successor regulation thereto), as it may be amended from time to time.

         "S&P" means Standard & Poor's Ratings Group, a division of McGraw-Hill,
Inc., or if Standard & Poor's Ratings Group shall cease rating the specified
debt securities and such ratings ceases with respect thereto shall have been
transferred to a successor Person, such successor Person, provided that if
Standard & Poor's Ratings Group ceases rating the specified debt securities and
its ratings business with respect thereto shall not have been transferred to any
successor Person or such successor Person is Moody's, then "S&P" shall mean any
other nationally recognized rating agency selected in good faith by the Board of
Directors of the Company in a Board Resolution.

         "Sale and Lease-Back Transaction" means, with respect to any Person,
any direct or indirect arrangement pursuant to which Property is sold or
transferred by such Person or a subsidiary of such Person and is thereafter
leased back from the purchaser or transferee thereof by such Person or one of
its subsidiaries.

         "Securities Act" means the Securities Act of 1933, as amended.

         "Senior Debt" means any Indebtedness incurred by the Company, unless
the instrument under which such Indebtedness is incurred expressly provides that
it is subordinated in right of payment to the Senior Notes, provided that Senior
Debt will not include (a) any liability for federal, state, local or other taxes
owed or owing, (b) any Indebtedness owing to any Subsidiaries of the Company,
(c) any trade payables or (d) any Indebtedness that is incurred in violation of
this Indenture.

         "Senior Note" has the meaning stated in the first paragraph of this
Indenture and more particularly means any Senior Note authenticated and
delivered under this Indenture.

         "Senior Note Custodian" means the Trustee, as custodian for the
Depository with respect to the Senior Notes in global form, or any successor
entity thereto.

         "Senior Note Register" has the meaning specified in Section 2.3.

         "Series A Indenture" means the Indenture dated as of June 27, 1997
among the Company,



                                       22




<PAGE>   30



the subsidiary guarantors parties thereto, and Chase Bank of Texas, National
Association (formerly known as Texas Commerce Bank National Association), as
Trustee, providing for the issuance of the Series A Notes in the aggregate
principal amount of $175,000,000, as such may be amended and supplemented from
time to time.

         "Series A Issue Date" means the date on which the Series A Notes were
originally issued under the Series A Indenture.

         "Series A Notes" means the Company's 8-7/8% Senior Notes due July 1,
2007 issued pursuant to the Series A Indenture, as such may be amended or
supplemented from time to time.

         "Significant Subsidiary" means a Subsidiary that is a "significant
subsidiary" as defined in Rule 1-02(w) of Regulation S-X under the Securities
Act and the Exchange Act.

         "Special Record Date" means a date fixed by the Trustee pursuant to
Section 2.12 for the payment of Defaulted Interest.

         "Stated Maturity" when used with respect to a Senior Note or any
installment of interest thereon, means the date specified in such Senior Note as
the fixed date on which the principal of such Senior Note or such installment of
interest is due and payable.

         "Subordinated Indebtedness" means any Indebtedness of the Company or
any Guarantor that is subordinated in right of payment to the Senior Notes or
the Guarantees, as the case may be, and does not mature prior to one year
following the Stated Maturity of the Senior Notes.

         "Subsidiary" means a subsidiary of the Company other than an
Unrestricted Subsidiary; provided that Indrillers shall not be considered a
Subsidiary for purposes of this Indenture.

         "subsidiary" means, with respect to any Person, (i) any corporation
more than 50% of the outstanding Voting Stock of which is owned, directly or
indirectly, by such Person, or by one or more other subsidiaries or such Person,
or by such Person and one or more other subsidiaries of such Person, (ii) any
general partnership, joint venture or similar entity, more than 50% of the
outstanding partnership or similar interest of which is owned, directly or
indirectly, by such Person, or by one or more other subsidiaries of such Person,
or by such Person and one or more other subsidiaries of such Person and (iii)
any limited partnership of which such Person or any subsidiary of such Person is
a general partner.

         "Surviving Entity" has the meaning specified in Section 5.1.

         "Transaction Date" has the meaning specified within the definition of
"Consolidated Interest Coverage Ratio."



                                       23




<PAGE>   31



         "Trust Indenture Act" or "TIA" means the Trust Indenture Act of 1939,
as amended, as in force at the date as of which this Indenture was executed.

         "Trustee" means the Person named as the "Trustee" in the first
paragraph of this Indenture until a successor Trustee shall have become such
pursuant to the applicable provision of this Indenture, and thereafter "Trustee"
shall mean such successor Trustee.

         "U.S. Global Note" means a permanent Global Note that contains the text
referred to in footnotes 1 and 3 and the additional schedule referred to in
footnote 4 to the form of the Senior Note attached hereto as Exhibit A, and that
is deposited with the Senior Note Custodian and registered in the name of the
Depositary or its nominee, representing Senior Notes sold in reliance on Rule
144A or in reliance on another exemption from the registration requirements of
the Securities Act.

         "U.S. Government Obligations" means securities that are (i) direct
obligations of the United States of America for the payment of which its full
faith and credit is pledged; (ii) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States of
America the payment of which is unconditionally guaranteed as a full faith and
credit obligation by the United States of America, which, in either case under
clauses (i) or (ii) above, are not callable or redeemable at the option of the
issuers thereof; or (iii) depository receipts issued by a bank or trust company
as custodian with respect to any such U.S. Government Obligations or a specific
payment of interest on or principal of any such U.S. Government Obligation held
by such custodian for the account of the holder of a Depository receipt,
provided that (except as required by law) such custodian is not authorized to
make any deduction from the amount payable to the holder of such Depository
receipt from any amount received by the custodian in respect of the U.S.
Government Obligation evidenced by such Depository receipt.

         "Uniform Commercial Code" means the New York Uniform Commercial Code as
in effect from time to time.

         "Unrestricted Subsidiary" means any subsidiary of the Company that the
Company has classified as an Unrestricted Subsidiary and that has not been
reclassified as a Subsidiary pursuant to the terms of this Indenture.

         "Voting Stock" means with respect to any Person, securities of any
class or classes of Capital Stock in such Person entitling the holder thereof
(whether at all times or at the times that such class of Capital Stock has
voting power by reason of the happening of any contingency) to vote in the
election of members of the board of directors or comparable body of such Person.

         "Wholly Owned Subsidiary" means any Subsidiary to the extent (i) all of
the Capital Stock or other ownership interests in such Subsidiary, other than
any directors' qualifying shares mandated by applicable law, is owned directly
or indirectly by the Company or (ii) such Subsidiary is



                                       24




<PAGE>   32



organized in a foreign jurisdiction and is required by the applicable laws and
regulations of such foreign jurisdiction to be partially owned by the government
of such foreign jurisdiction or individual or corporate citizens of such foreign
jurisdiction in order for such Subsidiary to transact business in such foreign
jurisdiction, provided that the Company, directly or indirectly, owns the
remaining Capital Stock or ownership interest in such Subsidiary and, by
contract or otherwise, controls the management and business of such Subsidiary
and derives the economic benefits of ownership of such Subsidiary to
substantially the same extent as if such Subsidiary were a wholly owned
Subsidiary.

SECTION 1.2.      Incorporation by Reference of Trust Indenture Act.

                  This Indenture is subject to the mandatory provisions of the
TIA which are incorporated by reference in and made a part of this Indenture.
The following TIA terms have the following meanings:

         "indenture securities" means the Senior Notes.

         "indenture security holder" means a Holder.

         "indenture to be qualified" means this Indenture.

         "indenture trustee" or "institutional trustee" means the Trustee.

         "obligor" on the indenture securities means the Company and any other
obligor on the indenture securities.

         All other TIA terms used in this Indenture that are defined by the TIA,
defined by TIA reference to another statute or defined by Commission rule have
the meanings assigned to them by such definitions.

SECTION 1.3.      Rules of Construction.

                  Unless the context otherwise requires:

                  (1)      a term has the meaning assigned to it;

                  (2) an accounting term not otherwise defined has the meaning
         assigned to it in accordance with GAAP;

                  (3)      "or" is not exclusive;

                  (4)      "including" means including without limitation;



                                       25




<PAGE>   33



                  (5) words in the singular include the plural and words in the
         plural include the singular;

                  (6) the words "herein", "hereof" and "hereunder" and other
         words of similar import refer to this Indenture as a whole and not to
         any particular Article, Section or other subdivision;

                  (7) provisions apply to successive events and transactions;

                  (8) references to agreements and other instruments include
         subsequent amendments and waivers but only to the extent not prohibited
         by this Indenture; and

                  (9) unless otherwise expressly provided herein, the principal
         amount of any Preferred Stock shall be the greater of (i) the maximum
         liquidation value of such Preferred Stock or (ii) the maximum mandatory
         redemption or mandatory repurchase price with respect to such Preferred
         Stock.

                                   ARTICLE 2.

                                THE SENIOR NOTES

SECTION 2.1.  Form and Dating.

              (a) General. The Senior Notes, together with the Trustee's
certificate of authentication and the Guarantors' notation of Guarantees, shall
be substantially in the form set forth in Exhibit A hereto. The Senior Notes may
have notations, legends or endorsements required by law, stock exchange rule or
usage. Each Senior Note shall be dated the date of its authentication. The
Senior Notes shall be in denominations of $1,000 and integral multiples thereof.
The Initial Senior Notes and the Exchange Notes will be the same except that the
Private Placement Legend and paragraph 18 will be omitted from the Exchange
Notes.

              The terms and provisions contained in the Senior Notes shall
constitute, and are hereby expressly made, a part of this Indenture and the
Company, the Guarantors and the Trustee, by their execution and delivery of this
Indenture, expressly agree to such terms and provisions and to be bound thereby.

              (b) Initial Senior Notes. Initial Senior Notes, with the notations
of the Guarantees endorsed thereon, shall be issued in the form of one or more
permanent Global Notes in definitive fully registered form without coupons.
Senior Notes offered and sold to QIBs in reliance on Rule 144A, shall be issued
initially in the form of the U.S. Global Notes, which shall be deposited on
behalf of the purchasers of the Senior Notes represented thereby with the Senior
Note Custodian, and registered in the name of the Depository or a nominee of the
Depository, duly executed by the



                                       26




<PAGE>   34



Company and authenticated by the Trustee as hereinafter provided. The aggregate
principal amount of the U.S. Global Notes may from time to time be increased or
decreased by adjustments made on the records of the Trustee and the Depository
or its nominee as hereinafter provided. Initial Senior Notes offered and sold in
reliance on Regulation S shall be issued initially in the form of the Regulation
S Global Note, which shall be deposited on behalf of the purchasers of the
Senior Notes represented thereby with the Senior Note Custodian, and registered
in the name of the Depository or the nominee of the Depository for the accounts
of designated agents holding on behalf of Euroclear or Cedel, duly executed by
the Company and authenticated by the Trustee as hereinafter provided. During the
"40-day distribution compliance period" (as defined in Regulation S) (the "40-
day restricted period") beneficial interests in the Regulation S Global Note
shall be held only through Euroclear or Cedel, and, pursuant to the Depository's
procedures, Indirect Participants that hold a beneficial interest in the
Regulation S Global Note shall not be able to transfer such interest to a person
that takes delivery thereof in the form of an interest in the U.S. Global Notes.
Following the termination of the 40-day restricted period, beneficial interests
in the Regulation S Global Notes shall be exchanged for beneficial interests in
U.S. Global Notes and beneficial interests in the U.S. Global Notes shall be
exchanged for beneficial interests in the Regulation S Global Notes, pursuant to
the Applicable Procedures. The aggregate principal amount of the Regulation S
Global Notes may from time to time be increased or decreased by adjustments made
on the records of the Trustee and the Depository or its nominee, as the case may
be, in connection with transfers of interest as hereinafter provided.

              Each Global Note shall represent such of the outstanding Senior
Notes as shall be specified therein and each shall provide that it shall
represent the aggregate amount of outstanding Senior Notes from time to time
endorsed on Schedule A thereto and that the aggregate amount of outstanding
Senior Notes represented thereby may from time to time be reduced or increased,
as appropriate, to reflect exchanges, redemptions and transfers of interests.
Any endorsement of Schedule A of a Global Note to reflect the amount of any
increase or decrease in the amount of outstanding Senior Notes represented
thereby shall be made by the Trustee or the Senior Note Custodian, at the
direction of the Trustee, in accordance with instructions given by the Holder
thereof as required by Section 2.6 hereof.

              The provisions of the "Operating Procedures of the Euroclear
System" and "Terms and Conditions Governing Use of Euroclear" and the
"Management Regulations" and "Instructions to Participants" of Cedel shall be
applicable to interests in the Regulation S Global Notes that are held by
Participants through Euroclear or Cedel. The Trustee shall have no obligation to
notify Holders of any such procedures or to monitor or enforce compliance with
the same.

              Except as set forth in Section 2.6 hereof, the Global Notes may be
transferred, in whole and not in part, only to another nominee of the Depository
or to a successor of the Depository or its nominee.



                                       27




<PAGE>   35



              (c) Book-Entry Provisions. This Section 2.1(c) shall apply only to
Global Notes deposited with or on behalf of the Depository.

              The Company shall execute and the Trustee shall, in accordance
with this Section 2.1(c), authenticate and deliver the Global Notes that (i)
shall be registered in the name of the Depository or the nominee of the
Depository and (ii) shall be delivered by the Trustee to the Depository or
pursuant to the Depository's instructions or held by the Senior Note Custodian.

              Participants shall have no rights either under this Indenture with
respect to any Global Note held on their behalf by the Depository or by the
Senior Note Custodian as custodian for the Depository or under such Global Note,
and the Depository may be treated by the Company, the Trustee and any agent of
the Company or the Trustee as the absolute owner of such Global Note for all
purposes whatsoever. Notwithstanding the foregoing, nothing herein shall prevent
the Company, the Trustee or any agent of the Company or the Trustee from giving
effect to any written certification, proxy or other authorization furnished by
the Depository or impair, as between the Depository and its Participants, the
operation of customary practices of such Depository governing the exercise of
the rights of an owner of a beneficial interest in any Global Note.

              (d) Certificated Senior Notes. Senior Notes issued in certificated
form shall be substantially in the form of Exhibit A attached hereto (but
without including the text referred to in footnotes 1, 3 and 4 thereto) and
shall be printed, typewritten, lithographed or engraved or produced by any
combination of these methods or may be produced by any other method permitted by
the rules of any securities exchange on which the Senior Notes may be listed, as
evidenced by the execution of such Senior Notes.

              (e) Provisions Applicable to Forms of Notes. The Senior Notes may
also have such additional provisions, omissions, variations or substitutions as
are not inconsistent with the provisions of this Indenture, and may have such
letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with this Indenture,
any applicable law or with any rules made pursuant thereto or with the rules of
any securities exchange or governmental agency or as may be determined
consistently herewith by the Officers of the Company executing such Senior
Notes, as conclusively evidenced by their execution of such Senior Notes. All
Senior Notes will be otherwise substantially identical except as provided
herein.

              Subject to the provisions of this Article 2, a Holder of a Global
Note may grant proxies and otherwise authorize any Person to take any action
that a Holder is entitled to take under this Indenture or the Senior Notes.



                                       28




<PAGE>   36



SECTION 2.2.  Execution and Authentication.

              One Officer shall sign the Senior Notes for the Company by manual
or facsimile signature.

              If an Officer whose signature is on a Senior Note no longer holds
that office at the time a Senior Note is authenticated, the Senior Note shall
nevertheless be valid.

              A Senior Note shall not be valid until authenticated by the manual
signature of the Trustee. The signature shall be conclusive evidence that the
Senior Note has been authenticated under this Indenture. The form of Trustee's
certificate of authentication to be borne by the Senior Notes shall be
substantially as set forth in Exhibit A hereto.

              The Trustee shall authenticate (i) Initial Senior Notes for
original issue in an aggregate principal amount not to exceed $75,000,000 and
(ii) Exchange Notes for issue only in the Exchange Offer pursuant to the
Exchange Offer Registration Statement for a like principal amount of Initial
Senior Notes exchanged in such Exchange Offer, in each case upon the receipt of
a Company Order directing the Trustee to authenticate such Senior Notes and
certifying that all conditions precedent to the issuance of the relevant Senior
Notes contained herein have been complied with. The aggregate principal amount
of Senior Notes outstanding at any time may not exceed $75,000,000, except as
provided in Section 2.8 hereof.

              The Trustee may appoint an authenticating agent acceptable to the
Company to authenticate Senior Notes. Unless limited by the terms of such
appointment, an authenticating agent may authenticate Senior Notes whenever the
Trustee may do so. Each reference in this Indenture to authentication by the
Trustee includes authentication by such agent. An authenticating agent has the
same rights as an Agent to deal with the Company or an Affiliate of the Company.



                                       29




<PAGE>   37



SECTION 2.3.  Registrar and Paying Agent.

              The Company shall maintain (i) an office or agency where Senior
Notes may be presented for registration of transfer or for exchange
("Registrar"), (ii) an office or agency where Senior Notes may be presented for
payment ("Paying Agent"), and (iii) and an office or agency where notices or
demands to or upon the Company and the Guarantors in respect of the Senior Notes
and this Indenture may be saved. The Registrar shall keep a register of the
Senior Notes and of their transfer and exchange (the "Securities Register"). The
Company may appoint one or more co-registrars and one or more additional paying
agents except as otherwise provided in this Indenture. The term "Registrar"
includes any co-registrar and the term "Paying Agent" includes any additional
paying agent. The Company may change any Paying Agent or Registrar without
notice to any Holder. The Company shall notify the Trustee in writing of the
name and address of any Agent not a party to this Indenture. If the Company
fails to appoint or maintain another entity as Registrar or Paying Agent, the
Trustee shall act as such. The Company or any of its Subsidiaries may act as
Paying Agent or Registrar.

              The Company initially appoints The Depository Trust Company
("DTC") to act as Depository with respect to the Global Notes.

              The Company initially appoints the Trustee (at the Corporate Trust
Office of the Trustee) to act as the Registrar and Paying Agent and to act as
Senior Note Custodian with respect to the Global Notes.

SECTION 2.4.  Paying Agent to Hold Money in Trust.

              The Company shall require each Paying Agent other than the Trustee
to agree in writing that the Paying Agent will hold in trust for the benefit of
Holders or the Trustee all money held by the Paying Agent for the payment of
principal of, premium, if any, on, interest on, and Special Interest, if any,
on, the Senior Notes, and shall notify the Trustee of any default by the Company
in making any such payment. While any such default continues, the Trustee may
require a Paying Agent to pay all money held by it to the Trustee. The Company
at any time may require a Paying Agent to pay all money held by it to the
Trustee. Upon payment over to the Trustee, the Paying Agent (if other than the
Company or a Subsidiary) shall have no further liability for the money. If the
Company or a Subsidiary acts as Paying Agent, it shall segregate and hold in a
separate trust fund for the benefit of the Holders all money held by it as
Paying Agent. Upon any bankruptcy or reorganization proceedings relating to the
Company, the Trustee shall serve as Paying Agent for the Senior Notes.



                                       30




<PAGE>   38



SECTION 2.5.  Computation of Interest.

              Interest on the Senior Notes shall be computed on the basis of a
360-day year comprised of twelve 30-day months.

SECTION 2.6.  Transfer and Exchange.

              (a) Transfer and Exchange of Global Notes. The transfer and
exchange of beneficial interests in Global Notes shall be effected through the
Depository, in accordance with this Indenture and the Applicable Procedures,
which shall include restrictions on transfer comparable to those set forth
herein to the extent required by the Securities Act. Beneficial interests in a
Global Note may be transferred to Persons who take delivery thereof in the form
of a beneficial interest in the same Global Note in accordance with the transfer
restrictions set forth in the legend in subsection (e) of this Section 2.6.
Transfers of beneficial interests in the Global Notes to Persons required to
take delivery thereof in the form of an interest in another Global Note shall be
permitted as follows:

              (i)   U.S. Global Note to Regulation S Global Note. Prior to the
                    expiration of the 40-day restricted period, an owner of a
                    beneficial interest in a U.S. Global Note deposited with the
                    Depository (or the Senior Note Custodian) will not be
                    permitted to transfer its interest to a Person who wishes to
                    take delivery thereof in the form of an interest in the
                    Regulation S Global Note. If, at any time after the
                    expiration of the 40-day restricted period, an owner of a
                    beneficial interest in a U.S. Global Note deposited with the
                    Depository (or the Senior Note Custodian) wishes to transfer
                    its beneficial interest in such U.S. Global Note to a Person
                    who is required or permitted to take delivery thereof in the
                    form of an interest in a Regulation S Global Note, such
                    owner shall, subject to the Applicable Procedures, exchange
                    or cause the exchange of such interest for an equivalent
                    beneficial interest in a Regulation S Global Note as
                    provided in this Section 2.6(a)(i). Upon receipt by the
                    Trustee of (1) instructions given in accordance with the
                    Applicable Procedures from a Participant directing the
                    Trustee to credit or cause to be credited a beneficial
                    interest in the Regulation S Global Note in an amount equal
                    to the beneficial interest in the U.S. Global Note to be
                    exchanged, (2) a written order given in accordance with the
                    Applicable Procedures containing information regarding the
                    Participant account of the Depository and the Euroclear or
                    Cedel account to be credited with such increase, and (3) a
                    certificate in the form of Exhibit B-1 hereto given by the
                    owner of such beneficial interest stating that the transfer
                    of such interest has been made in compliance with the
                    transfer restrictions applicable to the Global Notes and
                    pursuant to and in accordance with Rule 903 or Rule 904 of
                    Regulation S, then the Trustee, as Registrar, shall instruct
                    the Depository to reduce or cause to be reduced the
                    aggregate



                                       31




<PAGE>   39



                    principal amount at Maturity of the applicable U.S. Global
                    Note and to increase or cause to be increased the aggregate
                    principal amount at Maturity of the applicable Regulation S
                    Global Note by the principal amount at Maturity of the
                    beneficial interest in the U.S. Global Note to be exchanged
                    or transferred, to credit or cause to be credited to the
                    account of the Person specified in such instructions, a
                    beneficial interest in the Regulation S Global Note equal to
                    the reduction in the aggregate principal amount at Maturity
                    of the U.S. Global Note, and to debit, or cause to be
                    debited, from the account of the Person making such exchange
                    or transfer the beneficial interest in the U.S. Global Note
                    that is being exchanged or transferred.

              (ii)  Regulation S Global Note to U.S. Global Note. Prior to the
                    expiration of the 40-day restricted period, an owner of a
                    beneficial interest in a Regulation S Global Note deposited
                    with the Depository (or the Senior Note Custodian) will not
                    be permitted to transfer its interest to a Person who wishes
                    to take delivery thereof in the form of an interest in a
                    U.S. Global Note. If, at any time, after the expiration of
                    the 40-day restricted period, an owner of a beneficial
                    interest in a Regulation S Global Note deposited with the
                    Depository or with the Senior Note Custodian wishes to
                    transfer its beneficial interest in such Regulation S Global
                    Note to a Person who is required or permitted to take
                    delivery thereof in the form of an interest in a U.S. Global
                    Note, such owner shall, subject to the Applicable
                    Procedures, exchange or cause the exchange of such interest
                    for an equivalent beneficial interest in a U.S. Global Note
                    as provided in this Section 2.6(a)(ii). Upon receipt by the
                    Trustee of (1) instructions from Euroclear or Cedel, if
                    applicable, and the Depository, directing the Trustee, as
                    Registrar, to credit or cause to be credited a beneficial
                    interest in the U.S. Global Note equal to the beneficial
                    interest in the Regulation S Global Note to be exchanged,
                    such instructions to contain information regarding the
                    Participant account with the Depository to be credited with
                    such increase, (2) a written order given in accordance with
                    the Applicable Procedures containing information regarding
                    the participant account of the Depository and (3) a
                    certificate in the form of Exhibit B-2 attached hereto given
                    by the owner of such beneficial interest stating (A) if the
                    transfer is pursuant to Rule 144A, that the Person
                    transferring such interest in a Regulation S Global Note
                    reasonably believes that the Person acquiring such interest
                    in a U.S. Global Note is a QIB and is obtaining such
                    beneficial interest in a transaction meeting the
                    requirements of Rule 144A and any applicable blue sky or
                    securities laws of any state of the United States, (B) that
                    the transfer complies with the requirements of Rule 144
                    under the Securities Act or (C) if the transfer is pursuant
                    to any other exemption



                                       32




<PAGE>   40



                    from the registration requirements of the Securities Act,
                    that the transfer of such interest has been made in
                    compliance with the transfer restrictions applicable to the
                    Global Notes and pursuant to and in accordance with the
                    requirements of the exemption claimed, such statement to be
                    supported by an Opinion of Counsel from the transferee or
                    the transferor in form and substance reasonably acceptable
                    to the Company and to the Registrar and, in each case, in
                    accordance with any applicable securities laws of any state
                    of the United States or any other applicable jurisdiction,
                    then the Trustee, as Registrar, shall instruct the
                    Depository to reduce or cause to be reduced the aggregate
                    principal amount at maturity of such Regulation S Global
                    Note and to increase or cause to be increased the aggregate
                    principal amount at maturity of the applicable U.S. Global
                    Note by the principal amount at maturity of the beneficial
                    interest in the Regulation S Global Note to be exchanged or
                    transferred, and the Trustee, as Registrar, shall instruct
                    the Depository, concurrently with such redemption, to credit
                    or cause to be credited to the account of the Person
                    specified in such instructions a beneficial interest in the
                    applicable U.S. Global Note equal to the reduction in the
                    aggregate principal amount at maturity of such Regulation S
                    Global Note and to debit or cause to be debited from the
                    account of the Person making such transfer the beneficial
                    interest in the Regulation S Global Note that is being
                    exchanged or transferred.

         (b) Transfer and Exchange of Certificated Senior Notes. When
Certificated Senior Notes are presented by a Holder to the Registrar with a
request to register the transfer of the Certificated Senior Notes or to exchange
such Certificated Senior Notes for an equal principal amount of Certificated
Senior Notes of other authorized denominations, the Registrar shall register the
transfer or make the exchange as requested only if the Certificated Senior Notes
are presented or surrendered for registration of transfer or exchange, are
endorsed and contain a signature guarantee or are accompanied by a written
instrument of transfer in form satisfactory to the Registrar duly executed by
such Holder or by his attorney and contains a signature guarantee, duly
authorized in writing and the Registrar received the following documentation
(all of which may be submitted by facsimile):

                    in the case of Certificated Senior Notes that are Transfer
                    Restricted Senior Notes, such request shall be accompanied
                    by the following additional information and documents, as
                    applicable:

                    (A)  if such Transfer Restricted Senior Note is being
                         delivered to the Registrar by a Holder for registration
                         in the name of such Holder, without transfer, or such
                         Transfer Restricted Senior Note is being transferred to
                         the Company, a certification to that effect from such



                                       33




<PAGE>   41



                         Holder (in substantially the form of Exhibit B-3
                         hereto); or

                    (B)  if such Transfer Restricted Senior Note is being
                         transferred to a QIB in accordance with Rule 144A under
                         the Securities Act or pursuant to an exemption from
                         registration in accordance with Rule 144 under the
                         Securities Act or in an offshore transaction pursuant
                         to and in compliance with Rule 904 under the Securities
                         Act or pursuant to an effective registration statement
                         under the Securities Act, a certification to that
                         effect from such Holder (in substantially the form of
                         Exhibit B-3 hereto); or

                    (C)  if such Transfer Restricted Senior Note is being
                         transferred in reliance on any other exemption from the
                         registration requirements of the Securities Act, a
                         certification to that effect from such Holder (in
                         substantially the form of Exhibit B-3 hereto) and an
                         Opinion of Counsel from such Holder or the transferee
                         reasonably acceptable to the Company and to the
                         Registrar to the effect that such transfer is in
                         compliance with the Securities Act.

                (c)      Transfer of a Beneficial Interests in Global Notes for 
Certificated Senior Notes.

                (i)  The Global Notes that are Transfer Restricted Senior Notes
                     or the Exchange Global Notes, as the case may be, shall be
                     exchanged by the Company for one or more Certificated
                     Senior Notes representing Initial Senior Notes or Exchange
                     Notes, as the case may be, if (x) the Depositary (i) has
                     notified the Company that it is unwilling or unable to
                     continue as, or ceases to be, a "Clearing Agency"
                     registered under Section 17A of the Exchange Act and (ii) a
                     successor to the Depositary registered as a "Clearing
                     Agency" under Section 17A of the Exchange Act is not able
                     to be appointed by the Company within 90 calendar days or
                     (y) the Depositary is at any time unwilling or unable to
                     continue as Depositary and a successor to the Depositary is
                     not able to be appointed by the Company within 90 calendar
                     days or (iii) the Company, at its option, delivers a notice
                     in the form of an Officers' Certificate that it elects to
                     cause the issuance of Certificated Senior Notes. If an
                     Event of Default occurs and is continuing, the Company
                     shall, at the request of the Holder thereof, exchange all
                     or part of a Global Note that is a Transfer Restricted
                     Senior Note or an Exchange Global Note, as the case may be,
                     for one or more Certificated Senior Notes representing
                     Initial Senior Notes or Exchange Notes, as the case may be;
                     provided that the principal amount of each of such
                     Certificated Senior Notes, and such Global Note,



                                       34




<PAGE>   42



                     after such exchange, shall be $1,000 or an integral
                     multiple thereof. Whenever a Global Note is exchanged as a
                     whole for one or more Certificated Senior Notes, it shall
                     be surrendered by the Holder thereof to the Trustee for
                     cancellation. Whenever a Global Note is exchanged in part
                     for one or more Certificated Senior Notes, it shall be
                     surrendered by the Holder thereof to the Trustee and the
                     Trustee shall make the appropriate notations to Schedule A
                     thereof pursuant to Section 2.1 hereof. All Certificated
                     Senior Notes or Exchange Notes, as the case may be, issued
                     in exchange for a Global Note or any portion thereof shall
                     be registered in such names, and delivered, as the
                     Depositary shall instruct the Trustee. Any Certificated
                     Senior Notes issued pursuant to this Section 2.6(c)(i)
                     shall include the Private Placement Legend, except as
                     otherwise provided for by Section 2.6 hereof. Interests in
                     a Global Note may not be exchanged for Certificated Senior
                     Notes other than as provided in this Section 2.6. If a
                     beneficial interest in a Transfer Restricted Senior Note is
                     being transferred, the following additional documents and
                     information must be submitted (including by facsimile):

                     (A)  if such beneficial interest is being transferred to
                          the Person designated by the Depository as being the
                          beneficial owner, a certification to that effect from
                          such Person (in substantially the form of Exhibit B-4
                          hereto);

                     (B)  if such beneficial interest is being transferred to a
                          QIB in accordance with Rule 144A under the Securities
                          Act or pursuant to an exemption from registration in
                          accordance with Rule 144 under the Securities Act or
                          in an offshore transaction pursuant to and in
                          compliance with Rule 904 under the Securities Act or
                          pursuant to an effective registration statement under
                          the Securities Act, a certification to that effect
                          from the transferor (in substantially the form of
                          Exhibit B-4 hereto);

                     (C)  if such beneficial interest is being transferred in
                          reliance on any other exemption from the registration
                          requirements of the Securities Act, a certification to
                          that effect from the transferor (in substantially the
                          form of Exhibit B-4 hereto) and an Opinion of Counsel
                          from the transferee or the transferor reasonably
                          acceptable to the Company and to the Registrar to the
                          effect that such transfer is in compliance with the
                          Securities Act, in which case the Trustee or the
                          Senior Note Custodian, at the direction of the
                          Trustee, shall, in accordance with the standing
                          instructions and procedures existing between the
                          Depository and the Senior Note Custodian, cause the
                          aggregate



                                       35




<PAGE>   43



                          principal amount of U.S. Global Notes or Regulation S
                          Global Notes, as applicable, to be reduced accordingly
                          and, following such reduction, the Company shall
                          execute and, the Trustee shall authenticate and
                          deliver to the transferee a Certificated Senior Note
                          in the appropriate principal amount.

               (ii)   Certificated Senior Notes issued in exchange for a
                      beneficial interest in a U.S. Global Note or Regulation S
                      Global Note, as applicable, pursuant to this Section
                      2.6(c) shall be registered in such names and in such
                      authorized denominations as the Depository, pursuant to
                      instructions from its Participants or Indirect
                      Participants or otherwise, shall instruct the Trustee. The
                      Trustee shall deliver such Certificated Senior Notes to
                      the Persons in whose names such Senior Notes are so
                      registered. Following any such issuance of Certificated
                      Senior Notes, the Trustee, as Registrar, shall instruct
                      the Depository to reduce or cause to be reduced the
                      aggregate principal amount at maturity of the applicable
                      Global Note to reflect the transfer.

         (d) Restrictions on Transfer and Exchange of Global Notes.
Notwithstanding any other provision of this Indenture (other than the provisions
set forth in subsection (e) of this Section 2.6), a Global Note may not be
transferred as a whole except by the Depository to a nominee of the Depository
or by a nominee of the Depository to the Depository or another nominee of the
Depository or by the Depository or any such nominee to a successor Depository or
a nominee of such successor Depository. Any Holder of a beneficial interest in a
Global Note shall, by acceptance of such Global Note, agree that transfers of
beneficial interests in such Global Note may be effected only through a book
entry system maintained by the Holder of such Global Note (or its agent), and
that ownership of a beneficial interest in the Senior Notes represented hereby
shall be required to be reflected in book entry form. Interests of beneficial
owners in a Global Note may be transferred in accordance with the rules and
procedures of the Depositary (or its successors).

         (e)    Legends.

         (i)    Except as permitted by the following paragraphs (ii), (iii) and
                (iv), each Senior Note certificate evidencing Global Notes and
                Certificated Senior Notes (and all Senior Notes issued in
                exchange therefor or substitution thereof) shall bear a legend
                (the "Private Placement Legend") in substantially the following
                form:

                THIS SENIOR NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED
                UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE
                "SECURITIES ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED, SOLD,
                PLEDGED OR OTHERWISE



                                       36




<PAGE>   44



                TRANSFERRED WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT
                OR BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN THE SECOND
                SENTENCE HEREOF. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL
                INTEREST HEREIN, THE HOLDER (1) REPRESENTS THAT (A) IT IS A
                "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER
                THE SECURITIES ACT) (A "QIB"), OR (B) IT HAS ACQUIRED THIS
                SENIOR NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE WITH
                REGULATION S UNDER THE SECURITIES ACT, OR (2) AGREES THAT IT
                WILL NOT RESELL OR OTHERWISE TRANSFER THIS NOTE EXCEPT (A) TO
                THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) TO A PERSON WHOM THE
                SELLER REASONABLY BELIEVES IS A QIB PURCHASING FOR ITS OWN
                ACCOUNT OR FOR THE ACCOUNT OF A QIB IN A TRANSACTION MEETING THE
                REQUIREMENTS OF RULE 144A, (C) IN AN OFFSHORE TRANSACTION
                MEETING THE REQUIREMENTS OF RULE 903 OR 904 OF REGULATION S
                UNDER THE SECURITIES ACT, (D) IN A TRANSACTION MEETING THE
                REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (E) IN
                ACCORDANCE WITH ANOTHER EXEMPTION FROM THE REGISTRATION
                REQUIREMENTS OF THE SECURITIES ACT (AND BASED UPON AN OPINION OF
                COUNSEL ACCEPTABLE TO THE COMPANY) OR (F) PURSUANT TO AN
                EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN
                ACCORDANCE WITH THE APPLICABLE SECURITIES LAWS OF ANY STATE OF
                THE UNITED STATES OR ANY OTHER APPLICABLE JURISDICTION AND (3)
                AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS SENIOR
                NOTE OR AN INTEREST HEREIN IS TRANSFERRED A NOTICE SUBSTANTIALLY
                TO THE EFFECT OF THIS LEGEND. AS USED HEREIN, THE TERMS
                "OFFSHORE TRANSACTION" AND "UNITED STATES" HAVE THE MEANINGS
                GIVEN TO THEM BY RULE 902 OF REGULATION S UNDER THE SECURITIES
                ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO
                REFUSE TO REGISTER ANY TRANSFER OF THIS SENIOR NOTE IN VIOLATION
                OF THE FOREGOING.

          (ii)  Upon any sale or transfer of a Transfer Restricted Senior Note
                (including any Transfer Restricted Senior Note represented by a
                Global Note) pursuant to Rule 144 under the Securities Act or
                pursuant to an effective registration statement under the
                Securities Act:



                                       37




<PAGE>   45



                (A)   in the case of any Transfer Restricted Senior Note that is
                      a Certificated Senior Note, the Registrar shall permit the
                      Holder thereof to exchange such Transfer Restricted Senior
                      Note for a Certificated Senior Note that does not bear the
                      legend set forth in (i) above and rescind any restriction
                      on the transfer of such Transfer Restricted Senior Note
                      upon receipt of a certification from the transferring
                      Holder substantially in the form of Exhibit B-4 hereto;
                      and

                (B)   in the case of any Transfer Restricted Senior Note
                      represented by a Global Note, such Transfer Restricted
                      Senior Note shall not be required to bear the legend set
                      forth in (i) above, but shall continue to be subject to
                      the provisions of Section 2.6(a) and (b) hereof; provided,
                      however, that with respect to any request for an exchange
                      of a Transfer Restricted Senior Note that is represented
                      by a Global Note for a Certificated Senior Note that does
                      not bear the legend set forth in (i) above, which request
                      is made in reliance upon Rule 144, the Holder thereof
                      shall certify in writing to the Registrar that such
                      request is being made pursuant to Rule 144 (such
                      certification to be substantially in the form of Exhibit
                      B-4 hereto).

          (iii) Upon any sale or transfer of a Transfer Restricted Senior Note
                (including any Transfer Restricted Senior Note represented by a
                Global Note) in reliance on any exemption from the registration
                requirements of the Securities Act (other than exemptions
                pursuant to Rule 144A or Rule 144 under the Securities Act) in
                which the Holder or the transferee provides an Opinion of
                Counsel to the Company and the Registrar in form and substance
                reasonably acceptable to the Company and the Registrar (which
                Opinion of Counsel shall also state that the transfer
                restrictions contained in the legend are no longer applicable):

                (A)   in the case of any Transfer Restricted Senior Note that is
                      a Certificated Senior Note, the Registrar shall permit the
                      Holder thereof to exchange such Transfer Restricted Senior
                      Note for a Certificated Senior Note that does not bear the
                      legend set forth in (i) above and rescind any restriction
                      on the transfer of such Transfer Restricted Senior Note;
                      and

                (B)   in the case of any Transfer Restricted Senior Note
                      represented by a Global Note, such Transfer Restricted
                      Senior Note shall not be required to bear the legend set
                      forth in (i) above, but shall continue to be subject to
                      the provisions of Section 2.6(a) and (b) hereof.



                                       38




<PAGE>   46



          (iv)  By its acceptance of any Initial Senior Note represented by a
                certificate bearing the Private Placement Legend, each Holder
                of, and beneficial owner of an interest in, such Initial Senior
                Note acknowledges the restrictions on transfer of such Initial
                Senior Note set forth in the Private Placement Legend and under
                the heading "Notice to Investors" in the Offering Memorandum and
                agrees that it will transfer such Initial Senior Note only in
                accordance with the Private Placement Legend and the
                restrictions set forth under the heading "Notice to Investors"
                in the Offering Memorandum.

          (v)   Notwithstanding the foregoing, upon the occurrence of the
                Exchange Offer in accordance with the Registration Rights
                Agreement, the Company shall issue and, upon receipt of an
                authentication order in accordance with Section 2.2 hereof, the
                Trustee shall authenticate (i) one or more unrestricted Global
                Notes in aggregate principal amount equal to the principal
                amount of the restricted beneficial interests validly tendered
                and not properly withdrawn by Persons that certify in the letter
                of transmittal delivered in the Exchange Offer that they are not
                (x) broker-dealers, (y) Persons participating in the
                distribution of the Exchange Notes or (z) Persons who are
                affiliates (as defined in Rule 144 under the Securities Act) of
                the Company and accepted for exchange in the Exchange Offer and
                (ii) Certificated Senior Notes that do not bear the Private
                Placement Legend in an aggregate principal amount equal to the
                principal amount of the Certificated Senior Notes that are
                Transfer Restricted Senior Notes accepted for exchange in the
                Exchange Offer. Concurrently with the issuance of such Senior
                Notes, the Trustee shall cause the aggregate principal amount of
                the applicable Global Notes to be reduced accordingly and the
                Company shall execute and the Trustee shall authenticate and
                deliver to the Persons designated by the Holders of Certificated
                Senior Notes so accepted Certificated Senior Notes in the
                appropriate principal amount.

         (f)    Cancellation and/or Adjustment of Global Notes. At such time as
all beneficial interests in Global Notes have been exchanged for Certificated
Senior Notes, redeemed, repurchased or cancelled, all Global Notes shall be
returned to or retained and cancelled by the Trustee in accordance with Section
2.11 hereof. At any time prior to such cancellation, if any beneficial interest
in a Global Note is exchanged for Certificated Senior Notes, redeemed,
repurchased or cancelled, the principal amount of Senior Notes represented by
such Global Note shall be reduced accordingly and an endorsement shall be made
on such Global Note, by the Trustee or the Senior Notes Custodian, at the
direction of the Trustee, to reflect such reduction.

         (g)   General Provisions Relating to Transfers and Exchanges.



                                       39




<PAGE>   47



                  (i)      To permit registrations of transfers and exchanges,
                           the Company shall execute and the Trustee shall
                           authenticate Global Notes and Certificated Senior
                           Notes at the Registrar's request.

                  (ii)     No service charge shall be made to a Holder for any
                           registration of transfer or exchange, but the Company
                           may require payment of a sum sufficient to cover any
                           stamp or transfer tax or similar governmental charge
                           payable in connection therewith (other than any such
                           stamp or transfer taxes or similar governmental
                           charge payable upon exchange or transfer pursuant to
                           Sections 3.6, 4.7, 4.9 and 10.6 hereto).

                  (iii)    All Global Notes and Certificated Senior Notes issued
                           upon any registration of transfer or exchange of
                           Global Notes or Certificated Senior Notes shall be
                           the valid obligations of the Company, evidencing the
                           same debt, and entitled to the same benefits under
                           this Indenture, as the Global Notes or Certificated
                           Senior Notes surrendered upon such registration of
                           transfer or exchange.

                  (iv)     The Registrar shall not be required: (A) to issue, to
                           register the transfer of or to exchange Senior Notes
                           during a period beginning at the opening of fifteen
                           (15) Business Days before the day of any selection of
                           Senior Notes for redemption under Section 3.2 hereof
                           and ending at the close of business on the day of
                           selection, (B) to register the transfer of or to
                           exchange any Senior Note so selected for redemption
                           in whole or in part, except the unredeemed portion of
                           any Senior Note being redeemed in part, or (C) to
                           register the transfer of or to exchange a Senior Note
                           between a Record Date and the next succeeding
                           Interest Payment Date.

                  (v)      Prior to due presentment for the registration of a
                           transfer of any Senior Note, the Trustee, any Agent
                           and the Company may deem and treat the Person in
                           whose name any Senior Note is registered as the
                           absolute owner of such Senior Note for the purpose of
                           receiving payment of principal of and interest on
                           such Senior Notes and for all other purposes, and
                           neither the Trustee, any Agent nor the Company shall
                           be affected by notice to the contrary.

                  (vi)     The Trustee shall authenticate Global Notes and
                           Certificated Senior Notes in accordance with the
                           provisions of Section 2.2 hereof.



                                       40




<PAGE>   48



SECTION 2.7.  Holder Lists.

              The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
all Holders and shall otherwise comply with TIA ss. 312(a). If the Trustee is
not the Registrar, the Company shall furnish to the Trustee at least seven
Business Days before each Interest Payment Date and at such other times as the
Trustee may request in writing, a list in such form and as of such date as the
Trustee may reasonably require of the names and addresses of the Holders of
Senior Notes, and the Company shall otherwise comply with TIA ss. 312(a).

SECTION 2.8. Replacement of Senior Notes.

             If any mutilated Senior Note is surrendered to the Trustee, or the
Company and the Trustee receives evidence to its satisfaction of the
destruction, loss or theft of any Senior Note, the Company shall issue and the
Trustee, upon the written order of the Company signed by two Officers of the
Company, shall authenticate a replacement Senior Note if the Trustee's
requirements are met. If required by the Trustee or the Company, an indemnity
bond must be supplied by the Holder that is sufficient in the judgment of the
Trustee and the Company to protect the Company, the Guarantors, the Trustee, the
Paying Agent, the Registrar and any co-registrar from any loss which any of them
may suffer if a Senior Note is replaced. In case any such mutilated, destroyed,
lost or stolen Senior Note has become or is about to become due and payable, the
Company, in its discretion may, instead of issuing a new Senior Note, pay such
Senior Note.

SECTION 2.9.  Outstanding Senior Notes.

              The Senior Notes outstanding at any time are all the Senior Notes
authenticated by the Trustee except for those canceled by it, those delivered to
it for cancellation, those reductions in the interest in a Global Note effected
by the Trustee in accordance with the provisions hereof, and those described in
this Section as not outstanding. Except as set forth in Section 2.15 hereof, a
Senior Note does not cease to be outstanding because the Company or an Affiliate
of the Company holds the Senior Note.

              If a Senior Note is replaced pursuant to Section 2.8 hereof, it
ceases to be outstanding unless the Trustee receives proof satisfactory to it
that the replaced Senior Note is held by a bona fide purchaser.

              If the principal amount of any Senior Note is considered paid
under Section 4.1 hereof, it ceases to be outstanding and interest (including
Special Interest, if any) on it ceases to accrue.

              If the Paying Agent (other than the Company, a Guarantor, a
Subsidiary or an



                                       41




<PAGE>   49



Affiliate of any thereof) holds, on a Redemption Date or Maturity, money
sufficient to pay Senior Notes payable on that date, then on and after that date
such Senior Notes shall be deemed to be no longer outstanding and shall cease to
accrue interest (including Special Interest, if any).

SECTION 2.10. Reserved.

SECTION 2.11. Cancellation.

              The Company at any time may deliver Senior Notes to the Trustee
for cancellation. The Registrar and Paying Agent shall forward to the Trustee
any Senior Notes surrendered to them for registration of transfer, exchange or
payment. The Trustee and no one else shall cancel all Senior Notes surrendered
for registration of transfer, exchange, payment, replacement or cancellation and
shall upon the written request of the Company, return such canceled Senior Notes
to the Company. The Company may not issue new Senior Notes to replace Senior
Notes that it has paid or that have been delivered to the Trustee for
cancellation.

SECTION 2.12.  Payment of Interest; Interest Rights Preserved.

              Interest (including Special Interest, if any) on any Senior Note
which is payable, and is punctually paid or duly provided for, on any January 1
or July 1 (an "Interest Payment Date"), commencing on July 1, 1998, shall be
paid to the Person in whose name such Senior Note is registered at the close of
business on the Record Date for such interest payment, which shall be the
December 15 or June 15 (whether or not a Business Day) immediately preceding
such Interest Payment Date.

              Any interest on any Senior Note which is payable, but is not
punctually paid or duly provided for, on any Interest Payment Date (herein
called "Defaulted Interest") shall forthwith cease to be payable to the
registered Holder on the relevant Record Date, and, except as hereinafter
provided, such Defaulted Interest and any interest payable on such Defaulted
Interest may be paid by the Company, at its election, as provided in clause (a)
or (b) below:

              (a) The Company may elect to make payment of any Defaulted
Interest, and any interest payable on such Defaulted Interest, to the Persons in
whose names the Senior Notes are registered at the close of business on a
Special Record Date for the payment of such Defaulted Interest, which shall be
fixed in the following manner. The Company shall notify the Trustee in writing
of the amount of Defaulted Interest proposed to be paid on the Senior Notes and
the date of the proposed payment, and at the same time the Company shall deposit
with the Trustee an amount of money equal to the aggregate amount proposed to be
paid in respect of such Defaulted Interest (including Special Interest, if any)
or shall make arrangements satisfactory to the Trustee for such deposit prior to
the date of the proposed payment, such money when deposited to be held in trust
for the benefit of the Persons entitled to such Defaulted Interest as provided
in this clause (a).



                                       42




<PAGE>   50



Thereupon the Trustee shall fix a Special Record Date for the payment of such
Defaulted Interest which shall be not more than 15 calendar days and not less
than 10 calendar days prior to the date of the proposed payment and not less
than 10 calendar days after the receipt by the Trustee of the notice of the
proposed payment. The Trustee shall promptly notify the Company of such Special
Record Date and, in the name and at the expense of the Company, shall cause
notice of the proposed payment of such Defaulted Interest and the Special Record
Date therefor to be sent, first class mail, postage prepaid, to each Holder at
such Holder's address as it appears in the Senior Note Register, not less than
10 calendar days prior to such Special Record Date. Notice of the proposed
payment of such Defaulted Interest and the Special Record Date therefor having
been mailed as aforesaid, such Defaulted Interest shall be paid to the Persons
in whose names the Senior Notes are registered at the close of business on such
Special Record Date and shall no longer be payable pursuant to the following
clause (b).

              (b) The Company may make payment of any Defaulted Interest
(including Special Interest, if any), and any interest payable on such Defaulted
Interest, on the Senior Notes in any other lawful manner not inconsistent with
the requirements of any securities exchange on which the Senior Notes may be
listed, and upon such notice as may be required by such exchange, if, after
notice given by the Company to the Trustee of the proposed payment pursuant to
this clause, such manner of payment shall be deemed practicable by the Trustee.

              Subject to the foregoing provisions of this Section 2.12, each
Senior Note delivered under this Indenture upon registration of transfer of, or
in exchange for, or in lieu of, or in substitution for, any other Senior Note,
shall carry the rights to interest (and Special Interest, if any) accrued and
unpaid, and to accrue, which were carried by such other Senior Note.

SECTION 2.13.  Authorized Denominations.

              The Senior Notes shall be issuable in denominations of $1,000 and
any integral multiple thereof.

SECTION 2.14.  CUSIP Number.

              The Company in issuing the Senior Notes may use a "CUSIP" number,
and if it does so, the Trustee shall use the CUSIP number in notices of
redemption or exchange as a convenience to Holders; provided that any such
notice may state that no representation is made as to the correctness or
accuracy of the CUSIP number printed in the notice or on the Senior Notes and
that reliance may be placed only on the other identification numbers printed on
the Senior Notes. The Company shall promptly notify the Trustee of any change in
the CUSIP number.



                                       43




<PAGE>   51



SECTION 2.15. Treasury Senior Notes.

              In determining whether the Holders of the required principal
amount of Senior Notes have concurred in any direction, waiver or consent,
Senior Notes owned by the Company or any Guarantor, or by any Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with the Company or any Guarantor, shall be considered as though not
outstanding, except that for the purposes of determining whether the Trustee
shall be protected in relying on any such direction, waiver or consent, only
Senior Notes that a Responsible Officer knows are so owned shall be so
disregarded.

                                   ARTICLE 3.

                                   Redemption

SECTION 3.1.  Notices to Trustee.

              If the Company elects to redeem Senior Notes pursuant to Section
3.7 and paragraph 5 of the Senior Notes, it shall notify the Trustee in writing
of the Redemption Date, the principal amount of Senior Notes to be redeemed, the
Redemption Price and the Section of this Indenture and the paragraph of the
Senior Notes pursuant to which the redemption will occur.

              The Company shall give each notice to the Trustee provided for in
this Section at least 60 days before the Redemption Date unless the Trustee
consents to a shorter period. Such notice shall be accompanied by an Officers'
Certificate and an Opinion of Counsel from the Company to the effect that such
redemption will comply with the conditions herein and in the Senior Notes.



                                       44




<PAGE>   52



SECTION 3.2.  Selection of Senior Notes To Be Redeemed.

              If less than all the Senior Notes are to be redeemed at any time,
the Trustee shall select the Senior Notes to be redeemed on a pro rata basis, or
by any other method which the Trustee shall determine to be fair and appropriate
and which complies with any securities exchange and other applicable
requirements, provided that the Trustee may select for redemption in part only
Senior Notes in denominations larger than $1,000. In selecting Senior Notes to
be redeemed pursuant to this Section 3.2, the Trustee shall make such
adjustments, reallocations and eliminations as it shall deem proper so that the
principal amount at Stated Maturity of each Senior Note to be redeemed shall be
$1,000 or an integral multiple thereof, by increasing, decreasing or eliminating
any amount less than $1,000 which would be allocable to any Holder. If the Notes
to be redeemed are Certificated Senior Notes, the Certificated Senior Notes to
be redeemed shall be selected by the Trustee by prorating, as nearly as may be,
or by any other method which the Trustee shall determine to be fair and
appropriate and which complies with any securities exchange and other applicable
requirements, the principal amount of Certificated Senior Notes to be redeemed
among the Holders of Certificated Senior Notes registered in their respective
names. The Trustee in its discretion may determine the particular Senior Notes
(if there are more than one) registered in the name of any Holder which are to
be redeemed, in whole or in part. Provisions of this Indenture that apply to
Senior Notes called for redemption also apply to portions of Senior Notes called
for redemption. The Trustee shall notify the Company promptly of the Senior
Notes or portions of Senior Notes to be redeemed.

SECTION 3.3.  Notice of Redemption.

              At least 30 days but not more than 60 days before a date for
redemption of Senior Notes, the Company shall mail a notice of redemption by
first-class mail to each Holder of Senior Notes to be redeemed.

                  The notice shall identify the Senior Notes to be redeemed and
shall state:

                  (1)      the Redemption Date;

                  (2)      the Redemption Price;

                  (3)      the name and address of the Paying Agent;

                  (4) that Senior Notes called for redemption must be
         surrendered to the Paying Agent to collect the redemption price;

                  (5) if any Global Senior Note is being redeemed in part, the
         portion of the principal amount of such Senior Note to be redeemed and
         that, after the Redemption Date,



                                       45




<PAGE>   53



         the Global Senior Note, with a notation on Schedule A thereof adjusting
         the principal amount thereof to be equal to the unredeemed portion,
         will be returned to the Holder thereof;

                  (6) if any Certificated Senior Note is being redeemed in part,
         the portion of the principal amount of such Senior Note to be redeemed
         and that, after the Redemption Date, a new Certificated Senior Note or
         Certificated Senior Notes in principal amount equal to the unredeemed
         portion will be issued;

                  (7) if fewer than all the outstanding Senior Notes are to be
         redeemed, the identification and principal amounts of the particular
         Senior Notes to be redeemed;

                  (8) that, unless the Company defaults in making such
         redemption payment or the Paying Agent is prohibited from making such
         payment pursuant to the terms of this Indenture, interest on Senior
         Notes (or portion thereof) called for redemption ceases to accrue on
         and after the redemption date;

                  (9) that no representation is made as to the correctness or
         accuracy of the CUSIP number, if any, listed in such notice or printed
         on the Senior Notes;

                  (10) the paragraph of the Senior Notes and the Section of the
         Indenture pursuant to which the Senior Notes are being called for
         redemption; and

                  (11) any other information necessary to enable Holders to
         comply with the notice of redemption.

                  At the Company's request, the Trustee shall give the notice of
redemption in the Company's name and at the Company's expense. In such event,
the Company shall provide the Trustee with the information required by this
Section at least 45 days before the redemption date unless the Trustee consents
to a shorter period.

SECTION 3.4.      Effect of Notice of Redemption.

                  Once notice of redemption is mailed, Senior Notes called for
redemption become due and payable on the Redemption Date and at the Redemption
Price stated in the notice. Upon surrender to the Paying Agent, such Senior
Notes shall be paid at the Redemption Price stated in the notice, plus accrued
and unpaid interest to the Redemption Date. Failure to give notice or any defect
in the notice to any Holder shall not affect the validity of the notice to any
other Holder.



                                       46




<PAGE>   54



SECTION 3.5.  Deposit of Redemption Price.

              Prior to the Redemption Date, the Company shall deposit with the
Paying Agent (or, if the Company or a Subsidiary is the Paying Agent, shall
segregate and hold in trust) money sufficient to pay the Redemption Price of and
accrued and unpaid interest on all Senior Notes to be redeemed on that date
other than Senior Notes or portions of Senior Notes called for redemption which
have been delivered by the Company to the Trustee for cancellation.

              So long as the Company complies with the preceding paragraph and
the other provisions of this Article 3, interest on the Senior Notes to be
redeemed on the applicable Redemption Date shall cease to accrue from and after
such date and such Senior Notes or portions thereof shall be deemed not to be
entitled to any benefit under this Indenture except to receive payment of the
Redemption Price on the Redemption Date. If any Senior Note called for
redemption shall not be so paid upon surrender for redemption, then, from
Redemption Date until such principal is paid, interest shall be paid on the
unpaid principal and, to the extent permitted by law, on any accrued but unpaid
interest thereon, in each case at the rate prescribed therefor by this Indenture
and such Senior Notes.

SECTION 3.6.  Senior Notes Redeemed in Part.

              Upon surrender and cancellation of a Certificated Senior Note that
is redeemed in part, the Company shall issue and the Trustee shall authenticate
and deliver to the surrendering Holder (at the Company's expense) a new
Certificated Senior Note equal in principal amount to the unredeemed portion of
the Certificated Senior Note surrendered and canceled, provided that each such
Certificated Senior Note shall be in a principal amount at Stated Maturity of
$1,000 or an integral multiple thereof.

              Upon surrender of a Global Senior Note that is redeemed in part,
the Paying Agent shall forward such Global Senior Note to the Trustee who shall
make a notation on Schedule A thereof to reduce the principal amount of such
Global Senior Note to an amount equal to the unredeemed portion of such Global
Note.

SECTION 3.7.  Optional Redemption.

              (a) Except as set forth in subsection (b) of this Section 3.7, the
Company shall not have the option to redeem the Senior Notes prior to July 1,
2002. On or after such date, the Company shall have the option to redeem the
Senior Notes , in whole or in part upon not less than 30 days' nor more than 60
days' notice, at the Redemption Prices (expressed as percentages of principal
amount at Stated Maturity), if redeemed during the twelve month period beginning
July 1 of the years indicated below, in each case, together with any interest
accrued and unpaid to the Redemption Date:



                                       47




<PAGE>   55

<TABLE>
<CAPTION>


Year                                        Percentage
- ----                                        ----------
<S>                                         <C>

2002                                        104.4375%
2003                                        102.9580%
2004                                        101.4792%
2005 and thereafter                         100.0000%
</TABLE>

              (b) Notwithstanding the foregoing, at any time on or before June
27, 2000, the Company may, at its option, redeem up to a maximum of 30% of the
aggregate principal amount at Stated Maturity of the Senior Notes with the net
cash proceeds of one or more Qualified Equity Offerings at a Redemption Price
equal to 108.875% of the principal amount thereof, plus accrued and unpaid
interest thereon to the Redemption Date; provided that at least $50,000,000
aggregate principal amount at Stated Maturity of the Senior Notes shall remain
outstanding immediately after the occurrence of any such redemption; and
provided, further, that each such redemption shall occur within 90 days of the
closing of such Qualified Equity Offering.

              (c) Optional redemptions under this Indenture are subject to
Section 4.16 hereof.

                                   ARTICLE 4.

                                    Covenants

SECTION 4.1.  Payment of Senior Notes.

              The Company shall promptly pay the principal of, premium, if any,
on and interest on the Senior Notes on the dates and in the manner provided in
the Senior Notes and in this Indenture. Principal, premium and interest shall be
considered paid on the date due if on or before 10:00 a.m., Houston time, on
such date the Trustee or a Paying Agent, other than the Company or a Guarantor,
or an Affiliate of the Company or a Guarantor, holds in accordance with this
Indenture money sufficient to pay all principal, premium and interest then due
and the Trustee or the Paying Agent, as the case may be, is not prohibited from
paying such money to the Holders on that date pursuant to the terms of this
Indenture.

              The Company shall pay interest on overdue principal at the rate
specified therefor in the Senior Notes plus 1% per annum, and it shall pay
interest on overdue installments of interest (without regard to any applicable
grace period) at the same rate to the extent lawful.



                                       48




<PAGE>   56



SECTION 4.2.  Commission Reports.

              So long as any Senior Notes are outstanding, whether or not the
Company is subject to Section 13(a) or 15(d) of the Exchange Act, or any
successor provision thereto, the Company shall file with the Commission the
annual reports, quarterly reports and other documents which the Company would
have been required to file with the Commission pursuant to such Section 13(a) or
15(d) or any successor provision thereto if the Company were subject thereto,
such documents to be filed with the Commission on or prior to the respective
dates (the "Required Filing Dates") by which the Company would have been
required to file them. The Company shall also (whether or not it is required to
file reports with the Commission), within 30 days of each Required Filing Date,
(i) transmit by mail to all Holders of Senior Notes, as their names and
addresses appear in the Senior Note Register, without cost to such Holders or
Persons, and (ii) file with the Trustee, copies of the annual reports, quarterly
reports and other documents (without exhibits) which the Company has filed or
would have filed with the Commission pursuant to Section 13(a) or 15(d) of the
Exchange Act, any successor provisions thereto or this Section 4.2. The Company
shall not be required to file any report, document or other information with the
Commission if the Commission does not permit such filing.

SECTION 4.3.  Limitation on Indebtedness.

              The Company will not, and will not permit any of its Subsidiaries
to, directly or indirectly, incur any Indebtedness (including Acquired
Indebtedness) unless, after giving pro forma effect to the incurrence of such
Indebtedness, the Consolidated Interest Coverage Ratio for the Determination
Period would be at least 2.0 to 1.0 if such Indebtedness is incurred prior to
July 1, 1998 and at least 2.25 to 1.0 if such Indebtedness is incurred
thereafter. Notwithstanding the foregoing, the Company or any Subsidiary
(subject to the provisions of Sections 4.4 and 4.11) may incur Permitted
Indebtedness. Any Indebtedness of a Person existing at the time at which such
Person becomes a Subsidiary (whether by merger, consolidation, acquisition or
otherwise) shall be deemed incurred by such Subsidiary at the time at which it
becomes a Subsidiary.

SECTION 4.4.  Limitation on Subsidiary Indebtedness and Preferred Stock.

              The Company will not permit any Subsidiary to, directly or
indirectly, incur any Indebtedness or issue any Preferred Stock except:

         (i) Indebtedness or Preferred Stock issued to and held by the Company,
a Guarantor or a Wholly Owned Subsidiary, so long as any transfer of such
Indebtedness or Preferred Stock to a Person other than the Company, Guarantor or
a Wholly Owned Subsidiary will be deemed to constitute an incurrence of such
Indebtedness or Preferred Stock by the issuer thereof as of the date of such
transfer;



                                       49




<PAGE>   57



         (ii) Acquired Indebtedness or Preferred Stock of a Subsidiary issued
and outstanding prior to the date on which such Subsidiary was acquired by the
Company (other than Indebtedness or Preferred Stock issued in connection with or
in anticipation of such acquisition);

         (iii) Indebtedness or Preferred Stock outstanding on the Series A Issue
Date and listed in a schedule attached to the Series A Indenture;

         (iv) Indebtedness described in clauses (b), (c), (d), (e), (f), (g) and
(h) under the definition of "Permitted Indebtedness";

         (v)  Permitted Subsidiary Refinancing Indebtedness of such Subsidiary;

         (vi) Indebtedness or Preferred Stock issued in exchange for, or the
proceeds of which are used to refinance, repurchase or redeem, Indebtedness or
Preferred Stock described in clauses (i) and (iii) of this Section (the "Retired
Indebtedness or Stock"), provided that the Indebtedness or the Preferred Stock
so issued has (A) a principal amount or liquidation value, as the case may be,
not in excess of the principal amount or liquidation value of the Retired
Indebtedness or Stock plus related expenses for redemption and issuance, (B) a
final redemption date later than the stated maturity or final redemption date
(if any) of the Retired Indebtedness or Stock and (C) an Average Life at the
time of issuance of such Indebtedness or Preferred Stock that is greater than
the Average Life of the Retired Indebtedness or Stock;

         (vii) Indebtedness of a Subsidiary which represents the assumption by
such Subsidiary of Indebtedness of another Subsidiary in connection with a
merger of such Subsidiaries, provided that no Subsidiary or any successor (by
way of merger) thereto existing on the Series A Issue Date shall assume or
otherwise become responsible for any Indebtedness of an entity which was not a
Subsidiary on the Series A Issue Date, except to the extent that a Subsidiary
would be permitted to incur such Indebtedness under this Section; and

         (viii) Non-Recourse Indebtedness incurred by a foreign Subsidiary not
constituting a Guarantor.



                                       50




<PAGE>   58



SECTION 4.5.  Limitation on Restricted Payments.

              (a) The Company will not, and will not permit any of its
Subsidiaries to, make any Restricted Payment, unless at the time of and after
giving effect to the proposed Restricted Payment, (i) no Default shall have
occurred and be continuing (or would result therefrom), (ii) the Company could
incur at least $1.00 of additional Indebtedness under the tests described in the
first sentence of Section 4.3 of this Indenture and (iii) the aggregate amount
of all Restricted Payments declared or made on or after the Series A Issue Date
by the Company or any Subsidiary shall not exceed the sum of (A) 50% (or if such
Consolidated Net Income shall be a deficit, minus 100% of such deficit) of the
aggregate Consolidated Net Income accrued during the period beginning on the
first day of the fiscal quarter in which the Series A Issue Date occurred and
ending on the last day of the fiscal quarter ending immediately prior to the
date of such proposed Restricted Payment, minus 100% of the amount of any
writedowns, write-offs and other negative extraordinary charges not otherwise
reflected in Consolidated Net Income during such period, plus (B) an amount
equal to the aggregate net cash proceeds received by the Company, subsequent to
the Series A Issue Date, from the issuance or sale (other than to a Subsidiary)
of shares of its Capital Stock (excluding Redeemable Stock, but including
Capital Stock issued upon the exercise of options, warrants or rights to
purchase Capital Stock (other than Redeemable Stock) of the Company) and the
liability (expressed as a positive number) as expressed on the face of a balance
sheet in accordance with GAAP in respect of any Indebtedness of the Company or
any of its Subsidiaries, or the carrying value of Redeemable Stock, which has
been converted into, exchanged for or satisfied by the issuance of shares of
Capital Stock (other than Redeemable Stock) of the Company, subsequent to the
Series A Issue Date, plus (C) 100% of the net reduction in Restricted
Investments, subsequent to the Series A Issue Date, in any Person, resulting
from payments of interest on Indebtedness, dividends, repayments of loans or
advances, or other transfers of Property (but only to the extent such interest,
dividends, repayments or other transfers of Property are not included in the
calculation of Consolidated Net Income), in each case to the Company or any
Subsidiary from any Person (including, without limitation, from Unrestricted
Subsidiaries) or from redesignations of Unrestricted Subsidiaries as
Subsidiaries (valued in each case as provided in the definition of
"Investments"), not to exceed in the case of any Person the amount of Restricted
Investments previously made by the Company or any Subsidiary in such Person and
in each such case which was treated as a Restricted Payment.

              (b) The foregoing provisions will not prevent (i) the payment of
any dividend on Capital Stock of any class within 60 days after the date of its
declaration if at the date of declaration such payment would be permitted by
this Indenture; (ii) any repurchase or redemption of Capital Stock or
Subordinated Indebtedness of the Company or a Subsidiary made by exchange for
Capital Stock of the Company (other than Redeemable Stock), or out of the net
cash proceeds from the substantially concurrent issuance or sale (other than to
a Subsidiary) of Capital Stock of the Company (other than Redeemable Stock),
provided that the net cash proceeds from such sale are



                                       51




<PAGE>   59



excluded from computations under Section 4.5(a)(iii)(B) above to the extent that
such proceeds are applied to purchase or redeem such Capital Stock or
Subordinated Indebtedness; (iii) so long as no Default shall have occurred and
be continuing or should occur as a consequence thereof, any repurchase or
redemption of Subordinated Indebtedness of the Company or a Subsidiary solely in
exchange for, or out of the net cash proceeds from the substantially concurrent
sale of, new Subordinated Indebtedness of the Company or a Subsidiary, so long
as such Subordinated Indebtedness is permitted under Section 4.3 of this
Indenture and (1) is subordinated to the Senior Notes at least to the same
extent as the Subordinated Indebtedness so exchanged, purchased or redeemed, (2)
has a stated maturity later than the stated maturity of the Subordinated
Indebtedness so exchanged, purchased or redeemed and (3) has an Average Life at
the time incurred that is greater than the remaining Average Life of the
Subordinated Indebtedness so exchanged, purchased or redeemed; (iv) Investments
subsequent to the Series A Issue Date in any Joint Ventures, foreign
Subsidiaries not constituting Guarantors and Indrillers in an aggregate amount
not to exceed $10,000,000 and (v) redemptions subsequent to the Series A Issue
Date of the Series A Preferred Stock issued and outstanding on the Series A
Issue Date for an aggregate redemption price of not more than $1,000,000.
Notwithstanding the foregoing, the amount available for Investments in Joint
Ventures and foreign Subsidiaries pursuant to clause (iv) of the preceding
sentence may be increased by the aggregate amount received by the Company and
its Subsidiaries subsequent to the Series A Issue Date from a Joint Venture or a
foreign Subsidiary on or before the date of such proposed Investment resulting
from payments of interest on Indebtedness, dividends, repayments of loans or
advances or other transfers of Property made to such Joint Venture or foreign
Subsidiary (but only to the extent such interest dividends, repayments or other
transfers of Property are not included in the calculation of Consolidated Net
Income). Restricted Payments permitted to be made as described in the first
sentence of this Section 4.5(b) will be excluded in calculating the amount of
Restricted Payments thereafter, except that any such Restricted Payments
permitted to be made pursuant to clause (iv) will be included in calculating the
amount of Restricted Payments made pursuant to such clause (iv) thereafter.

              (c) For purposes of this Section 4.5, if a particular Restricted
Payment involves a non-cash payment, including a distribution of assets, then
such Restricted Payment shall be deemed to be an amount equal to the cash
portion of such Restricted Payment, if any, plus an amount equal to the Fair
Market Value of the non-cash portion of such Restricted Payment.



                                       52




<PAGE>   60



SECTION 4.6.  Limitations on Dividends and Other Payment Restrictions Affecting
Subsidiaries.


              The Company will not, and will not permit any Subsidiary, directly
or indirectly, to create, enter into any agreement with any Person or otherwise
cause or suffer to exist or become effective any consensual encumbrance or
restriction of any kind which by its terms restricts the ability of any
Subsidiary to (a) pay dividends, in cash or otherwise, or make any other
distributions on its Capital Stock to the Company or any Subsidiary, (b) pay any
Indebtedness owed to the Company or any Subsidiary, (c) make loans or advances
to the Company or any Subsidiary or (d) transfer any of its Property or assets
to the Company or any Subsidiary except any encumbrance or restriction contained
in any agreement or instrument:

                           (i) existing on the Issue Date (including those under
         the Series A Indenture);

                           (ii) relating to any Property or assets acquired
         after the Series A Issue Date, so long as such encumbrance or
         restriction relates only to the Property or assets so acquired and is
         not and was not created in anticipation of such acquisition;

                           (iii) relating to any Acquired Indebtedness of any
         Subsidiary at the date on which such Subsidiary was acquired by the
         Company or any Subsidiary (other than Indebtedness incurred in
         anticipation of such acquisition);

                           (iv) effecting a refinancing of Indebtedness incurred
         pursuant to an agreement referred to in the foregoing clauses (i)
         through (iii), so long as the encumbrances and restrictions contained
         in any such refinancing agreement are no more restrictive than the
         encumbrances and restrictions contained in such agreements;

                           (v) constituting customary provisions restricting
         subletting or assignment of any lease of the Company or any Subsidiary
         or provisions in license agreements or similar agreements that restrict
         the assignment of such agreement or any rights thereunder;

                           (vi) constituting restrictions on the sale or other
         disposition of any Property securing Indebtedness as a result of a
         Permitted Lien on such Property; or

                           (vii) constituting any temporary encumbrance or
         restriction with respect to a Subsidiary pursuant to an agreement that
         has been entered into for the sale or disposition of all or
         substantially all of the Capital Stock of, or Property and assets of,
         such Subsidiary.



                                       53




<PAGE>   61



SECTION 4.7.  Limitation on Asset Sales.

              (a) The Company will not engage in, and will not permit any
Subsidiary to engage in, any Asset Sale unless (a) except in the case of (i) an
Asset Sale resulting from the requisition of title to, seizure or forfeiture of
any Property or assets or any actual or constructive total loss or an agreed or
compromised total loss or (ii) a Bargain Purchase Contract, the Company or such
Subsidiary, as the case may be, receives consideration at the time of such Asset
Sale at least equal to the Fair Market Value of the Property; (b) at least 75%
of such consideration consists of Cash Proceeds (or the assumption of
Indebtedness of the Company or such Subsidiary relating to the Capital Stock or
Property or asset that was the subject of such Asset Sale and the unconditional
release of the Company or such Subsidiary from such Indebtedness); (c) after
giving effect to such Asset Sale, the total non-cash consideration held by the
Company from all such Asset Sales made after the Series A Issue Date does not
exceed $10,000,000; and (d) the Company delivers to the Trustee an Officers'
Certificate certifying that such Asset Sale complies with clauses (a), (b) and
(c). The Company or such Subsidiary, as the case may be, may apply the Net
Available Proceeds from each Asset Sale (x) to the acquisition of one or more
Replacement Assets, or (y) to repurchase or repay Senior Debt (with a permanent
reduction of availability in the case of revolving credit borrowings); provided
that such acquisition or such repurchase or repayment shall be made within 270
days after the consummation of the relevant Asset Sale.

              (b) Any Net Available Proceeds from any Asset Sale made after the
Series A Issue Date that are not used to so acquire Replacement Assets or to
repurchase or repay Senior Debt within 270 days after consummation of the
relevant Asset Sale constitute "Excess Proceeds." When the aggregate amount of
Excess Proceeds exceeds $15,000,000, the Company shall within 30 days thereafter
(or at any time after receipt of Excess Proceeds but prior to there being
$15,000,000 of Excess Proceeds, the Company may, at its option) make a pro rata
offer (an "Asset Sale Offer") to purchase from all holders of Senior Notes and
all holders of other Senior Debt containing provisions similar to those set
forth herein with respect to offers to purchase or redeem such Indebtedness with
the proceeds of sales of assets (including, without limitation, the Series A
Notes) (collectively, "Asset Sale Senior Debt") an aggregate principal amount of
Indebtedness equal to the Excess Proceeds, at a price in cash (the "Asset Sale
Offer Purchase Price") equal to 100% of the outstanding principal amount at
Stated Maturity thereof plus accrued interest, if any, to the Asset Sale
Purchase Date, in accordance with the procedures set forth in Section 4.7(c).
Upon completion of such Asset Sale Offer, the amount of Excess Proceeds shall be
reset to zero and the Company may use any remaining amount for general corporate
purposes.

              Notwithstanding the foregoing, the Company may, at its option,
elect to limit the Asset Sale Offer referred to above to Asset Sale Senior Debt
other than the Series A Notes. In such event, the Company shall (i) allocate the
Excess Proceeds pro rata among all Asset Sale Senior Debt (for this purpose,
including, without limitation, the Series A Notes), (ii) make the Asset Sale
Offer only with respect to that portion of the Excess Proceeds allocated to the
Asset Sale Senior Debt other



                                       54




<PAGE>   62



than the Series A Notes, and (iii) retain the portion of the Excess Proceeds
allocated to the Series A Notes and use such funds to make an "Asset Sale Offer"
as defined in the Series A Indenture.

              (c) Within 30 days of the date that the amount of Excess Proceeds
exceeds $15,000,000, the Company, or the Trustee at the request and expense of
the Company, shall send to each Holder by first class mail, postage prepaid, a
notice prepared by the Company stating:

                           (i) that an Asset Sale Offer is being made pursuant
         to this Section 4.7 and that all Senior Notes properly tendered will be
         accepted for payment, subject to proration in the event that the amount
         of Excess Proceeds is less than the aggregate Asset Sale Offer Purchase
         Price of all Senior Notes properly tendered pursuant to the Asset Sale
         Offer;

                           (ii) the Asset Sale Offer Purchase Price, the amount
         of Excess Proceeds that are available to be applied to purchase
         tendered Senior Notes, and the date Senior Notes are to be purchased
         pursuant to the Asset Sale Offer (the "Asset Sale Offer Purchase
         Date"), which date shall be a date no earlier than 30 days and not
         later than 40 days subsequent to the date such notice is mailed;

                           (iii) that any Senior Notes or portions thereof not
         properly tendered or accepted for payment will continue to accrue
         interest;

                           (iv) that, unless the Company defaults in the payment
         of the Asset Sale Offer Purchase Price with respect thereto, all Senior
         Notes or portions thereof accepted for payment pursuant to the Asset
         Sale Offer shall cease to accrue interest from and after the Asset Sale
         Offer Purchase Date;

                           (v) that any Holder electing to have any Senior Notes
         or portions thereof purchased pursuant to the Asset Sale Offer will be
         required to surrender such Senior Notes, with the form entitled "Option
         of Holder to Elect Purchase" on the reverse of such Senior Notes
         completed, to the Paying Agent at the address specified in the notice,
         prior to the close of business on the third Business Day preceding the
         Asset Sale Offer Purchase Date;

                           (vi) that any Holder shall be entitled to withdraw
         such election if the Paying Agent receives, not later than the close of
         business on the second Business Day preceding the Asset Sale Offer
         Purchase Date, a telegram, telex, facsimile transmission or letter,
         setting forth the name of the Holder, the principal amount of Senior
         Notes delivered for purchase, and a statement that such Holder is
         withdrawing such Holder's election to have such Senior Notes or
         portions thereof purchased pursuant to the Asset Sale Offer;

                           (vii) that any Holder electing to have Senior Notes
         purchased pursuant to the Asset Sale Offer must specify the principal
         amount at Stated Maturity that is being



                                       55




<PAGE>   63



         tendered for purchase, which principal amount at Stated Maturity must 
         be $1,000 or an integral multiple thereof;

                           (viii) if Certificated Senior Notes have been issued
         pursuant to Section 2.6(a), that any Holder of Certificated Senior
         Notes whose Certificated Senior Notes are being purchased only in part
         will be issued new Certificated Senior Notes equal in principal amount
         at Stated Maturity to the unpurchased portion of the Certificated
         Senior Note or Senior Notes surrendered, which unpurchased portion will
         be equal in principal amount at Stated Maturity to $1,000 or an
         integral multiple thereof;

                           (ix) that the Trustee will return to the Holder of a
         Global Senior Note that is being purchased in part, such Global Senior
         Note with a notation on Schedule A thereof adjusting the principal
         amount at Stated Maturity thereof to be equal to the unpurchased
         portion of such Global Senior Note; and

                           (x) the instructions and any other information
         necessary to enable any Holder to tender Senior Notes and to have such
         Senior Notes purchased, or to withdraw such tender, pursuant to this
         Section 4.7.

              (d) If the aggregate Asset Sale Offer Purchase Price of the Senior
Notes surrendered by Holders exceeds the amount of Excess Proceeds as indicated
in the notice required by Section 4.7(c) hereof, the Trustee shall select the
Senior Notes to be purchased on a pro rata basis based on the principal amount
of the Senior Notes tendered, with such adjustments as may be deemed appropriate
by the Trustee and to comply with any securities exchange and other applicable
requirements, so that only Senior Notes in denominations of $1,000 or integral
multiples thereof shall be purchased.

              (e) On or before the Asset Sale Offer Purchase Date, the Company
shall (i) accept for payment any Senior Notes or portions thereof properly
tendered and selected for purchase pursuant to the Asset Sale and Section 4.7(d)
hereof; (ii) irrevocably deposit with the Paying Agent, by 10:00 a.m., New York
City time, on such date, in immediately available funds, an amount equal to the
Asset Sale Offer Purchase Price in respect of all Senior Notes or portions
thereof so accepted; and (iii) deliver, or cause to be delivered, to the Trustee
the Senior Notes so accepted together with an Officers' Certificate listing the
Senior Notes or portions thereof tendered to the Company and accepted for
payment. The Paying Agent shall promptly send by first class mail, postage
prepaid, to each Holder of Senior Notes or portions thereof so accepted for
payment, payment in an amount equal to the Asset Sale Offer Purchase Price for
such Senior Notes or portions thereof. The Company shall publicly announce the
results of the Asset Sale Offer on or as soon as practicable after the Asset
Sale Offer Purchase Date. For purposes of this Section 4.7, the Trustee shall
act as the Paying Agent.



                                       56




<PAGE>   64



              (f) Upon surrender and cancellation of a Certificated Senior Note
that is purchased in part, the Company shall promptly issue and the Trustee
shall authenticate and deliver to the surrendering Holder of such Certificated
Senior Note a new Certificated Senior Note equal in principal amount to the
unpurchased portion of such surrendered Certificated Senior Note; provided that
each such new Certificated Senior Note shall be in a principal amount at Stated
Maturity of $1,000 or an integral multiple thereof.

              (g) Upon surrender of a Global Senior Note that is purchased in
part pursuant to an Asset Sale Offer, the Paying Agent shall forward such Global
Senior Note to the Trustee who shall make a notation on Schedule A thereof to
reduce the principal amount of such Global Senior Note to an amount equal to the
unpurchased portion of such Global Senior Note, as provided in Section 2.6
hereof.

              (h) Upon completion of an Asset Sale Offer (including payment of
the Asset Sale Offer Purchase Price for accepted Senior Notes), any surplus
Excess Proceeds that were subject to such offer shall cease to be Excess
Proceeds, the amount of Excess Proceeds shall be reset to zero and the Company
may use any remaining amount for general corporate purposes.

              (i) The Company shall comply with any applicable tender offer
rules (including, without limitation, any applicable requirements of Rule 14e-1
under the Exchange Act) in the event that an Asset Sale Offer is required under
the circumstances described herein.

              (j) Asset Sale Offers are subject to Section 4.16 hereof.



                                       57




<PAGE>   65



SECTION 4.8.  Limitation on Transactions with Affiliates.

              (a) Subsequent to the Issue Date, the Company will not, and will
not permit any Subsidiary to, directly or indirectly, enter into or permit to
exist any transaction or series of related transaction (including, but not
limited to, the purchase, sale or exchange of Property, the making of any
Investment, the giving of any guarantee or the rendering of any service with any
Affiliate of the Company, other than transactions among the Company and any
Guarantors or any Wholly Owned Subsidiaries) unless (i) such transaction or
series of related transactions is on terms no less favorable to the Company or
such Subsidiary than those that could be obtained in a comparable arm's length
transaction with a Person that is not such an Affiliate and (ii) (A) with
respect to a transaction or series of related transactions that has a Fair
Market Value in excess of $2,000,000 but less than $5,000,000, the Company
delivers an Officers' Certificate to the Trustee certifying that such
transaction or series of related transactions complies with clause (i) above; or
(B) with respect to a transaction or series of related transactions that has a
Fair Market Value equal to or in excess of $5,000,000, the transaction or series
of related transactions is approved by a majority of the Board of Directors of
the Company (including a majority of the disinterested directors), which
approval is set forth in a Board Resolution certifying that such transaction or
series of transactions complies with clause (i) above.

              (b) The foregoing provisions shall not be applicable to (i)
reasonable and customary compensation, indemnification and other benefits paid
or made available to an officer, director or employee of the Company or a
Subsidiary for services rendered in such person's capacity as an officer,
director or employee (including reimbursement or advancement of reasonable
out-of-pocket expenses and provisions of directors' and officers' liability
insurance) or (ii) the making of any Restricted Payment otherwise permitted by
this Indenture.

SECTION 4.9.  Change of Control.

              (a) Upon the occurrence of a Change of Control, each Holder will
have the right to require the Company to repurchase all of such Holder's Senior
Notes in whole or in part (the "Change of Control Offer") at a purchase price
(the "Change of Control Purchase Price") in cash equal to 101% of the aggregate
principal amount at Stated Maturity thereof, plus accrued and unpaid interest
thereon, if any, to the Change of Control Payment Date on the terms described
below.

              (b) Within 30 days following any Change of Control, the Company or
the Trustee (at the expense of the Company) will mail a notice to each Holder
and to the Trustee stating,

                           (i) that a Change of Control has occurred and a
         Change of Control Offer is being made pursuant to this Section 4.9, and
         that, although Holders are not required to tender their Senior Notes,
         all Senior Notes that are timely tendered will be accepted for payment;



                                       58




<PAGE>   66



                           (ii) the Change of Control Purchase Price and the
         repurchase date, which will be no earlier than 30 days and no later
         than 60 days after the date such notice is mailed (the "Change of
         Control Payment Date");

                           (iii) that any Senior Note or portion thereof
         accepted for payment pursuant to the Change of Control Offer (and duly
         paid for on the Change of Control Payment Date) will cease to accrue
         interest after the Change of Control Payment Date;

                           (iv) that any Senior Note or portion thereof not
         properly tendered will continue to accrue interest;

                           (v) that any Holder electing to have any Senior Notes
         or portions thereof purchased pursuant to a Change of Control Offer
         will be required to surrender such Senior Notes, with the form entitled
         "Option of Holder to Elect Purchase" on the reverse of such Senior
         Notes completed, to the Paying Agent at the address specified in the
         notice, prior to the close of business on the third Business day
         preceding the Change of Control Date;

                           (vi) that any Holder shall be entitled to withdraw
         such election if the Paying Agent receives, not later than the close of
         business on the second Business Day preceding the Change of Control
         Payment Date, a telegram, telex, facsimile transmission or letter,
         setting forth the name of the Holder, the principal amount of Senior
         Notes delivered for purchase, and a statement that such Holder is
         withdrawing such Holder's election to have such Senior Notes or
         portions thereof purchased pursuant to the Change of Control Offer;

                           (vii) that any Holder electing to have Senior Notes
         purchased pursuant to the Change of Control Offer must specify the
         principal amount at Stated Maturity that is being tendered for
         purchase, which principal amount at Stated Maturity must be $1,000 or
         an integral multiple thereof;

                           (viii) if Certificated Senior Notes have been issued
         pursuant to Section 2.6(a), that any Holder of Certificated Senior
         Notes whose Certificated Notes are being purchased only in part will be
         issued new Certificated Senior Notes equal in principal amount at
         Stated Maturity to the unpurchased portion of the Certificated Senior
         Note or Securities surrendered, which unpurchased portion will be equal
         in principal amount at Stated Maturity to $1,000 or an integral
         multiple thereof;

                           (ix) that the Trustee will return to the Holder of a
         Global Senior Note that is being purchased in part, such Senior Note
         with a notation on Schedule A thereof adjusting the principal amount at
         Stated Maturity thereof to be equal to the unpurchased portion of such
         Global Senior Note;



                                       59




<PAGE>   67



                           (x) the instructions and any other information
         necessary to enable any Holder to accept a Change of Control Offer or
         effect withdrawal of such acceptance; and

                           (xi) the instructions and any other information
         necessary to enable Holders to tender their Senior Notes and have such
         Senior Notes purchased pursuant to the Change of Control Offer.

                  (c) On or before the Change of Control Payment Date, the
Company shall (i) accept for payment any Senior Notes or portions thereof
properly tendered pursuant to the Change of Control Offer; (ii) irrevocably
deposit with the Paying Agent, by 10:00 a.m., New York City time, on such date,
in immediately available funds, an amount equal to the Change of Control
Purchase Price in respect of all Senior Notes or portions thereof so accepted,
including interest, if applicable; and (iii) deliver, or cause to be delivered,
to the Trustee the Senior Notes so accepted together with an Officers'
Certificate listing the Senior Notes or portions thereof tendered to the Company
and accepted for payment. The Paying Agent shall promptly send by first class
mail, postage prepaid, to each Holder of Senior Notes or portions thereof so
accepted for payment, payment in an amount equal to the Change of Control
Purchase Price for such Senior Notes or portions thereof. The Company shall
publicly announce the results of the Change of Control Offer on or as soon as
practicable after the Change of Control Payment Date. For purposes of this
Section 4.9, the Trustee shall act as the Paying Agent.

                  (d) Upon surrender and cancellation of a Certificated Senior
Note that is purchased in part pursuant to the Change of Control Offer, the
Company shall promptly issue and the Trustee shall authenticate and deliver to
the surrendering Holder of such Certificated Senior Note, a new Certificated
Note equal in principal amount at Stated Maturity to the unpurchased portion of
such surrendered Certificated Note; provided that each such new Certificated
Senior Note shall be in a principal amount of $1,000 at Stated Maturity or an
integral multiple thereof.

                  Upon surrender of a Global Senior Note that is purchased in
part pursuant to a Change of Control Offer, the Paying Agent shall forward such
Global Senior Note to the Trustee who shall make a notation on Schedule A
thereof to reduce the principal amount at Stated Maturity of such Global Note to
an amount equal to the unpurchased portion of such Global Senior Note, as
provided in Section 2.6 hereof.

                  (e) The Company will not be required to make a Change of
Control Offer upon a Change of Control if a third party makes the Change of
Control Offer in the manner, at the times and otherwise in compliance with the
requirements set forth in this Indenture applicable to a Change of Control Offer
made by the Company and repurchases all Senior Notes validly tendered and not
withdrawn under such Change of Control Offer.

                  (f) The Company will comply with any applicable tender offer
rules (including,



                                       60




<PAGE>   68



without limitation, any applicable requirements of Rule 14e-1 under the Exchange
Act) in the event that the Change of Control Offer is triggered under the
circumstances described herein.

              (g) Change of Control Offers are subject to Section 4.16 hereof.

SECTION 4.10.  Limitation on Liens.

              The Company will not, and will not permit any Subsidiary to,
directly or indirectly, create, affirm, incur, assume or suffer to exist any
Liens of any kind other than Permitted Liens on or with respect to any Property
or assets of the Company or such Subsidiary or any interest therein or any
income or profits therefrom, whether owned at the Series A Issue Date or
thereafter acquired, without effectively providing that the Senior Notes shall
be secured equally and ratably with (or prior to) the Indebtedness so secured
for so long as such obligations are so secured.

SECTION 4.11.  Limitation on Guarantees by Guarantors.

              The Company will not permit any Guarantor to guarantee the payment
of any Subordinated Indebtedness of the Company unless such guarantee shall be
subordinated to such Guarantor's Guarantee at least to the same extent as such
Subordinated Indebtedness is subordinated to the Senior Notes; provided that
this covenant will not be applicable to any guarantee of any Guarantor that (i)
existed at the time at which such Person became a Subsidiary of the Company and
(ii) was not incurred in connection with, or in contemplation of, such Person
becoming a Subsidiary of the Company.

SECTION 4.12.  Unrestricted Subsidiaries.

              (a) The Company may designate a subsidiary (including a newly
formed or newly acquired subsidiary) of the Company or any of its Subsidiaries
as an Unrestricted Subsidiary; provided that (i) immediately after giving effect
to the transaction, the Company could incur $1.00 of additional Indebtedness
pursuant to the first sentence of Section 4.3 and (ii) such designation is at
the time permitted under Section 4.5. Notwithstanding any provisions of this
covenant all subsidiaries of an Unrestricted Subsidiary will be Unrestricted
Subsidiaries.

              (b) The Company will not, and will not permit any of its
Subsidiaries to, take any action or enter into any transaction or series of
transactions that would result in a Person (other than a newly formed subsidiary
having no outstanding Indebtedness (other than Indebtedness to the Company or a
Subsidiary) at the date of determination) becoming a Subsidiary (whether through
an acquisition, the redesignation of an Unrestricted Subsidiary or otherwise)
unless, after giving effect to such action, transaction or series of
transactions on a pro forma basis, (i) the Company could incur at least $1.00 of
additional Indebtedness pursuant to the first sentence of Section 4.3 and (ii)
no Default or Event of Default would occur.



                                       61




<PAGE>   69



              (c) Subject to Sections 4.12(a) and (b), an Unrestricted
Subsidiary may be redesignated as a Subsidiary. The designation of a subsidiary
as an Unrestricted Subsidiary or the designation of an Unrestricted Subsidiary
as a Subsidiary in compliance with this Section 4.12 shall be made by the Board
of Directors pursuant to a Board Resolution delivered to the Trustee and shall
be effective as of the date specified in such Board Resolution, which shall not
be prior to the date such Board Resolution is delivered to the Trustee. Any
Unrestricted Subsidiary shall become a Subsidiary if it incurs any Indebtedness
other than Non-Recourse Indebtedness. If at any time Indebtedness of an
Unrestricted Subsidiary which was Non-Recourse Indebtedness no longer so
qualifies, such Indebtedness shall be deemed to have been incurred when such
Non-Recourse Indebtedness becomes Indebtedness.

SECTION 4.13.  Limitation on Sale and Lease-Back Transactions.

              The Company will not, and will not permit any Subsidiary to,
directly or indirectly, enter into, assume, guarantee or otherwise become liable
with respect to any Sale and Lease-Back Transaction unless (i) the proceeds from
such Sale and Lease-Back Transaction are at least equal to the Fair Market Value
of such Property being transferred and (ii) the Company or such Subsidiary would
have been permitted to enter into such transaction under the provisions of
Sections 4.3, 4.4 and 4.10.

SECTION 4.14.  Limitation on Line of Business.

              None of the Company or any of its Subsidiaries will directly or
indirectly engage to any substantial extent in any line or lines of business
activity other than a Related Business.

SECTION 4.15.  Limitation on Restrictive Covenants.

              The restrictive covenants set forth herein, including, without
limitation, those set forth in Sections 4.5, 4.7 and 4.8, shall be and shall be
deemed limited to the extent necessary so that the creation, existence and
effectiveness of such restrictive covenants shall not result in a breach of
Section 4.6 of the Series A Indenture.



                                       62




<PAGE>   70



SECTION 4.16. Limitation on Redemptions and Other Repayments of Notes and Series
A Notes.

              The Company will not optionally make any principal payment on, or
redeem, repurchase, defease (including in-substance or legal defeasance) or
otherwise acquire or retire for value (including pursuant to mandatory
repurchase covenants), prior to any scheduled principal payment, scheduled
sinking fund payment or other stated maturity (collectively, for purposes of
this covenant only, "redeem," and such action being a "redemption") the Senior
Notes unless, substantially concurrently with such redemption, the Company
redeems (or, if such redemption requires the consent of the holders of the
Series A Notes, offers to redeem) an aggregate principal amount of the Series A
Notes (rounded to the nearest integral multiple of $1,000) equal to the product
of (i) a fraction, the numerator of which is the aggregate principal amount of
the Senior Notes to be so redeemed (or for which such offer to redeem will be
made) and the denominator of which is the aggregate principal amount of the
Senior Notes outstanding immediately prior to such proposed redemption and (ii)
the aggregate principal amount of the Series A Notes outstanding immediately
prior to such proposed redemption.

              The Company will not optionally redeem the Series A Notes unless,
substantially concurrently with such redemption, the Company redeems (or, if
such redemption requires the consent of the holders of the Senior Notes, offers
to redeem) an aggregate principal amount of the Senior Notes (rounded to the
nearest integral multiple of $1,000) equal to the product of (i) a fraction, the
numerator of which is the aggregate principal amount of the Series A Notes to be
so redeemed (or for which such offer to redeem will be made) and the denominator
of which is the aggregate principal amount of the Series A Notes outstanding
immediately prior to such proposed redemption and (ii) the aggregate principal
amount of the Senior Notes outstanding immediately prior to such proposed
redemption.

SECTION 4.17.  Maintenance of Office or Agency.

              The Company shall maintain in The City of New York, an office or
agency where Senior Notes may be presented or surrendered for payment, where
Senior Notes may be surrendered for registration of transfer or exchange and
where notices and demands to or upon the Company in respect of the Senior Notes
and this Indenture may be served. Unless otherwise designated by the Company by
written notice to the Trustee such office or agency shall be the office of the
Trustee's agent, Chase Trust Company of New York, which is located at 55 Water
Street, North Building, Room 234, Windows 20 and 21, New York, New York 10041,
Attention: Vice President, Global Trust Services. The Company shall give prompt
written notice to the Trustee of the location, and any change in the location,
of such office or agency. If at any time the Company shall fail to maintain any
such required office or agency or shall fail to furnish the Trustee with the
address thereof, such presentations, surrenders, notices and demands may be made
or served at the Corporate Trust Office of the Trustee, and the Company hereby
appoints the Trustee its agent to receive all presentations, surrenders, notices
and demands.



                                       63




<PAGE>   71



              The Company may also from time to time designate one or more other
offices or agencies (in or outside of The City of New York) where the Senior
Notes may be presented or surrendered for any or all of such purposes, and may
from time to time rescind such designations; provided that no such designation
or rescission shall in any manner relieve the Company of its obligation to
maintain an office or agency in The City of New York, for such purposes. The
Company shall give prompt written notice to the Trustee of any such designation
and any change in the location of any such other office or agency.

SECTION 4.18.  Money for the Senior Note Payments to be Held in Trust.

              If the Company, any Subsidiary of the Company or any of their
respective Affiliates shall at any time act as Paying Agent with respect to the
Senior Notes, such Paying Agent shall, on or before each due date of the
principal of (and premium, if any) or interest on any of the Senior Notes,
segregate and hold in trust for the benefit of the Persons entitled thereto
money sufficient to pay the principal (and premium, if any) or interest so
becoming due until such money shall be paid to such Persons or otherwise
disposed of as herein provided, and shall promptly notify the Trustee of its
action or failure so to act.

              Whenever the Company shall have one or more Paying Agents with
respect to the Senior Notes, it shall, prior to or on each due date of the
principal of (and premium, if any) or interest on any of the Senior Notes,
deposit with a Paying Agent a sum sufficient to pay the principal (and premium,
if any) or interest so becoming due, such sum to be held in trust for the
benefit of the Persons entitled to such principal, premium or interest, and
(unless such Paying Agent is the Trustee) the Paying Agent shall promptly notify
the Trustee of the Company's action or failure so to act.

SECTION 4.19.  Corporate Existence.

              The Company will, and will cause each of its Subsidiaries to,
preserve and keep in full force and effect its corporate existence in accordance
with applicable law, except as permitted in Sections 5.1 and 5.2; provided,
however, that the Company may terminate the corporate existence of any
Subsidiary if, in the good faith judgment of the Board of Directors of the
Company, such termination is desirable in the conduct of the business of the
Company and its Subsidiaries and is not disadvantageous in any material respect
to the Holders of the Senior Notes.



                                       64




<PAGE>   72



SECTION 4.20.  Maintenance of Property.

              The Company shall cause all Property used in the conduct of its
business or the business of any of its Subsidiaries to be maintained and kept in
good condition, repair and working order (reasonable wear and tear excepted) and
supplied with all necessary equipment and shall cause to be made all necessary
repairs, renewals, replacements, betterments and improvements thereof, all as,
in the judgment of the Company, may be necessary so that the business carried on
in connection therewith may be properly and advantageously conducted at all
times; provided that nothing in this Section 4.20 shall prevent the Company from
discontinuing the operation or maintenance of any of such Property if such
discontinuance is, in the judgment of the Company, desirable in the conduct of
its business or the business of any of its Subsidiaries and not disadvantageous
in any material respect to the Holders of the Senior Notes.

SECTION 4.21.  Payment of Taxes and Other Claims.

              The Company shall pay or discharge or cause to be paid or
discharged, before the same shall become delinquent, (a) all material taxes,
assessments and governmental charges levied or imposed upon the Company or any
of its Subsidiaries or upon the income, profits or property of the Company or
any of its Subsidiaries and (b) all material lawful claims for labor, materials
and supplies which, if unpaid, might by law become a Lien upon the Property or
assets of the Company or any of its Subsidiaries; provided that the Company
shall not be required to pay or discharge or cause to be paid or discharged any
such tax, assessment, charge or claim whose amount, applicability or validity is
being contested in good faith by appropriate proceedings and for which adequate
reserves in accordance with GAAP or other appropriate provision has been made.

SECTION 4.22.  Compliance Certificate; Notice of Default or Event of Default.

              (a) The Company shall deliver to the Trustee within 120 days after
the end of each fiscal year of the Company ending after the date hereof, an
Officers' Certificate (which shall be signed by officers satisfying the
requirements of Section 314 of the Trust Indenture Act) stating whether or not,
to the best knowledge of such officers, the Company has complied with all
conditions and covenants under this Indenture, and, if the Company shall be in
Default, specifying all such Defaults and the nature thereof of which such
officer may have knowledge.

              (b) The year-end financial statements delivered pursuant to
Section 4.2 above shall be accompanied by a written statement of the Company's
independent public accountants (who shall be a firm of established national
reputation reasonably satisfactory to the Trustee) that in making the
examination necessary for certification of such financial statements nothing has
come to their attention which would lead them to believe that the Company or any
of its Subsidiaries has violated the provisions of Section 4.1, 4.3, 4.4, 4.5,
4.7, 4.9 or 4.19 hereof or of Article 5 of this Indenture or, if any such
violation has occurred, specifying the nature and period of existence



                                       65




<PAGE>   73



thereof, it being understood that such accountants shall not be liable directly
or indirectly to any person for any failure to obtain knowledge of any such
violation, and it being further understood that such statement may not be
provided to the extent contrary to the then current recommendations of the
accountants' governing body.

              (c) The Company will, so long as any of the Senior Notes are
outstanding, deliver to the Trustee, within 5 days of any Officer becoming aware
of (i) any Default or Event of Default or (ii) any event of default under any
other mortgage, indenture or instrument referred to in Section 6.1(e), an
Officers' Certificate specifying such Default, Event of Default or other event
of default and what action the Company or applicable Subsidiary is taking or
proposes to take with respect thereto.

SECTION 4.23.  Further Instruments and Acts.

              Upon request of the Trustee, the Company will execute and deliver
such further instruments and do such further acts as may be reasonably necessary
or proper to carry out more effectively the purpose of this Indenture.

SECTION 4.24. Prohibition on Company and Guarantors Becoming Investment
Companies.

              None of the Company or the Guarantors shall become an "investment
company" as defined in the Investment Company Act of 1940, as amended.

SECTION 4.25. Stay, Extension and Usury Laws.

              The Company and each of the Guarantors covenant (to the extent
that it may lawfully do so) that it shall not at any time insist upon, plead, or
in any manner whatsoever claim or take the benefit of advantage of, any stay,
extension or usury law wherever enacted, now or at any time hereafter in force,
that may affect the covenants or the performance of this Indenture; and the
Company and each of the Guarantors (to the extent that it may lawfully do so)
hereby expressly waive all benefit or advantage of any such law, and covenants
that it shall not, by resort to any such law, hinder, delay or impede the
execution of any power herein granted to the Trustee, but shall suffer and
permit the execution of every such power as though no such law has been enacted.



                                       66




<PAGE>   74



                                    ARTICLE 5

              Consolidation, Merger, Conveyance, Lease or Transfer

SECTION 5.1. Consolidation, Merger, Conveyance, Lease or Transfer.

              (a) The Company will not, in any transaction or series of
transactions, consolidate with or merge into any other Person (other than a
merger of a Subsidiary into the Company in which the Company is the continuing
corporation), or continue in any new jurisdiction, or sell, convey, assign,
transfer, lease or otherwise dispose of all or substantially all of the Property
and assets of the Company and the Subsidiaries, taken as a whole, to any Person,
unless

                           (i) either (A) the Company shall be the continuing
                  corporation or (B) the corporation (if other than the Company)
                  formed by such consolidation or into which the Company is
                  merged, or the Person which acquires, by sale, assignment,
                  conveyance, transfer, lease or disposition, all or
                  substantially all of the Property and assets of the Company
                  and the Subsidiaries, taken as a whole (such corporation or
                  Person, the "Surviving Entity"), shall be a corporation
                  organized and validly existing under the laws of the United
                  States of America, any political subdivision thereof or any
                  state thereof or the District of Columbia, and shall expressly
                  assume, by a supplemental indenture, the due and punctual
                  payment of the principal of (and premium, if any) and interest
                  on all the Senior Notes and the performance of the Company's
                  covenants and obligations under this Indenture;

                           (ii) immediately before and after giving effect to
                  such transaction or series of transactions on a pro forma
                  basis (including, without limitation, any Indebtedness
                  incurred or anticipated to be incurred in connection with or
                  in respect of such transaction or series of transactions), no
                  Event of Default or Default shall have occurred and be
                  continuing or would result therefrom;

                           (iii) immediately after giving effect to such
                  transaction or series of transactions on a pro forma basis
                  (including, without limitation, any Indebtedness incurred or
                  anticipated to be incurred in connection with or in respect of
                  such transaction or series of transactions), the Company (or
                  the Surviving Entity if the Company is not continuing) shall
                  have a Consolidated Net Worth equal to or greater than the
                  Consolidated Net Worth of the Company immediately prior to
                  such transactions; and

                           (iv) immediately after giving effect to any such
                  transaction or series of transactions on a pro forma basis as
                  if such transaction or series of transactions had occurred on
                  the first day of the Determination Period, the Company (or the
                  Surviving



                                       67




<PAGE>   75



                  Entity if the Company is not continuing) would be permitted to
                  incur $1.00 of additional Indebtedness pursuant to the
                  provisions of the first sentence of Section 4.3.

                  (b) The provision of Section 5.1(a)(iv) above shall not apply
to any merger or consolidation into or with, or any such transfer of all or
substantially all of the Property and assets of the Company and the Subsidiaries
taken as a whole into, the Company.

SECTION 5.2. Officers' Certificate and Opinion of Counsel.

              In connection with any consolidation, merger, continuance,
transfer of assets or other transactions contemplated by Section 5.1, the
Company shall deliver, or cause to be delivered, to the Trustee, in form and
substance reasonably satisfactory to the Trustee, an Officers' Certificate and
an Opinion of Counsel, each stating that such consolidation, merger,
continuance, sale, assignment, conveyance or transfer and the supplemental
indenture in respect thereto comply with the provisions of this Indenture and
that all conditions precedent in this Indenture relating to such transactions
have been complied with.

SECTION 5.3. Substitution of Surviving Entity.

              Upon any transaction or series of transactions that are of the
type described in, and are effected in accordance with, this Article 5, the
Surviving Entity shall succeed to, and be substituted for, and may exercise
every right and power of, the Company under this Indenture and the Senior Notes
with the same effect as if such Surviving Entity had been named as the Company
in this Indenture; and when a Surviving Person duly assumes all of the
obligations and covenants of the Company pursuant to this Indenture and the
Senior Notes, except in the case of a lease, the predecessor Person shall be
relieved of all such obligations.

              If such Surviving Entity shall have succeeded to and been
substituted for the Company, such Surviving Entity may cause to be signed,, and
may issue either in its own name or in the name of the Company prior to such
succession any or all of the Senior Notes delivered to the Trustee; and, upon
the order of such Surviving Entity, instead of the Company, and subject to all
the terms, conditions and limitations in this Indenture prescribed, the Trustee
shall authenticate and shall deliver any Senior Notes which previously shall
have been signed and delivered by the officers of the Company to the Trustee for
authentication, and any Senior Notes which such Surviving Entity thereafter
shall cause to be signed and delivered to the Trustee for that purpose (in each
instance with endorsements of Guarantees thereon by the Guarantors). All of the
Senior Notes so issued and so endorsed shall in all respects have the same legal
rank and benefit under this Indenture as the Senior Notes theretofore or
thereafter issued and endorsed in accordance with the terms of this Indenture
and the Guarantee as though all of such Senior Notes had been issued and
endorsed at the date of the execution hereof.



                                       68




<PAGE>   76



              In case of any such consolidation, merger, continuance, sale,
transfer, conveyance or other disposal, such changes in phraseology and form
(but not in substance) may be made in the Senior Notes thereafter to be issued
or the Guarantees to be endorsed thereon as may be appropriate.

              For all purposes of this Indenture and the Senior Notes,
Subsidiaries of any Surviving Entity will, upon such transaction or series of
transactions, become Subsidiaries or Unrestricted Subsidiaries as provided
pursuant to this Indenture and all Indebtedness, and all Liens on Property or
assets, of the Surviving Entity and its Subsidiaries immediately prior to such
transaction or series of transactions shall be deemed to have been incurred upon
such transaction or series of transactions.

                                    ARTICLE 6

                              Defaults and Remedies

SECTION 6.1.  Events of Default.

              Whenever used herein, an "Event of Default" means any one of the
following events (whatever the reason for such Event of Default and whether it
shall be voluntary or involuntary or be effected by operation of law or pursuant
to any judgment, decree or order of any court or any order, rule or regulation
of any administrative or governmental body):

              (a) default in the payment of interest on any Senior Note pursuant
to this Indenture when the same becomes due and payable, and the continuance of
such Default for a period of 30 days;

              (b) default in the payment of principal of (or premium, if any,
on) any Senior Note when the same becomes due and payable, whether upon
Maturity, upon optional redemption, required repurchase (including pursuant to a
Change of Control Offer or an Asset Sale Offer) or otherwise or the failure to
make an offer to purchase any such Senior Note as required pursuant to the
provisions of the Senior Notes and this Indenture;

              (c) the Company fails to comply with any of its covenants or
agreements contained in Sections 4.3, 4.4, 4.5, 4.7, 4.9, 4.13 and 5.1 of this
Indenture;

              (d) the Company defaults in the performance, or breach, of any
covenant or warranty of the Company in this Indenture (other than a covenant or
warranty addressed in clause (a), (b) or (c) above) and continuance of such
Default or breach for a period of 30 days after written notice thereof has been
given to the Company by the Trustee or to the Company and the Trustee by Holders
of at least 25% of the aggregate principal amount at Stated Maturity of the
outstanding Senior Notes;

              (e) Indebtedness of the Company or any Subsidiary is not paid when
due within



                                       69




<PAGE>   77



the applicable grace period, if any, or is accelerated by the holders thereof
and, in either case, the principal amount of such unpaid or accelerated
Indebtedness exceeds $10,000,000;

              (f) the entry by a court of competent jurisdiction of one or more
final judgments against the Company or any Subsidiary in an uninsured or
unindemnified aggregate amount in excess of $5,000,000 which is not discharged,
waived, appealed, stayed, bonded or satisfied for a period of 60 consecutive
days;

              (g) the entry by a court having jurisdiction in the premises of
(i) a decree or order for relief in respect of the Company or any Significant
Subsidiary in an involuntary case or proceeding under U.S. bankruptcy laws, as
now or hereafter constituted, or any other applicable Federal, state, or foreign
bankruptcy, insolvency, or other similar law or (ii) a decree or order adjudging
the Company or any Significant Subsidiary a bankrupt or insolvent, or approving
as properly filed a petition seeking reorganization, arrangement, adjustment or
composition of or in respect of the Company or any Significant Subsidiary under
U.S. bankruptcy laws, as now or hereafter constituted, or any other applicable
Federal, state or foreign bankruptcy, insolvency, or similar law, or appointing
a custodian, receiver, liquidator, assignee, trustee, sequestrator or other
similar official of the Company or any Significant Subsidiary or of any
substantial part of the Property or assets of the Company or any Significant
Subsidiary, or ordering the winding up or liquidation of the affairs of the
Company or any Significant Subsidiary, and the continuance of any such decree or
order for relief or any such other decree or order unstayed and in effect for a
period of 60 consecutive days;

              (h) (i) the commencement by the Company or any Significant
Subsidiary of a voluntary case or proceeding under U.S. bankruptcy laws, as now
or hereafter constituted, or any other applicable Federal, state or foreign
bankruptcy, insolvency or other similar law or of any other case or proceeding
to be adjudicated a bankrupt or insolvent; or (ii) the consent by the Company or
any Significant Subsidiary to the entry of a decree or order for relief in
respect of the Company or any Significant Subsidiary in an involuntary case or
proceeding under U.S. bankruptcy laws, as now or hereafter constituted, or any
other applicable Federal, state, or foreign bankruptcy, insolvency or other
similar law or to the commencement of any bankruptcy or insolvency case or
proceeding against the Company or any Significant Subsidiary; or (iii) the
filing by the Company or any Significant Subsidiary of a petition or answer or
consent seeking reorganization or relief under U.S. bankruptcy laws, as now or
hereafter constituted, or any other applicable Federal, state or foreign
bankruptcy, insolvency or other similar law; or (iv) the consent by the Company
or any Significant Subsidiary to the filing of such petition or to the
appointment of or taking possession by a custodian, receiver, liquidator,
assignee, trustee, sequestrator or similar official of the Company or any
Significant Subsidiary or of any substantial part of the Property or assets of
the Company or any Significant Subsidiary or of any substantial part of the
Property or assets of the Company or any Significant Subsidiary, or the making
by the Company or any Significant Subsidiary of an assignment for the benefit of
creditors; or (v) the admission by the Company or any Significant



                                       70




<PAGE>   78



Subsidiary in writing of its inability to pay its debts generally as they become
due; or (vi) the taking of corporate action by the Company or any Significant
Subsidiary in furtherance of any such action; or

              (i) any Guarantee shall for any reason cease to be, or be asserted
by the Company or any Guarantor, as applicable, not to be, in full force and
effect (except pursuant to the release of any such Guarantee in accordance with
the provisions of this Indenture).

SECTION 6.2.  Acceleration.

              If an Event of Default (other than an Event of Default described
in clause (g) or (h) of Section 6.1) occurs and shall be continuing, then in
each and every case the Trustee or the Holders of not less than 25% of the
outstanding aggregate principal amount at Stated Maturity of the Senior Notes
may declare the principal amount at Stated Maturity of the Senior Notes to be
due and payable immediately by a notice in writing to the Company (and to the
Trustee if given by Holders of such Senior Notes), and upon any such declaration
the principal amount at Stated Maturity of, premium, if any, on, any accrued and
unpaid interest on, and any other amounts payable in respect of, the Senior
Notes then outstanding will become and be immediately due and payable. If any
Event of Default specified in clause (g) or (h) of Section 6.1 occurs, the
principal amount at Stated Maturity of, premium, if any, and any accrued and
unpaid interest on, and any other amount payable in respect of, the Senior Notes
then outstanding shall become immediately due and payable without any
declaration or other act on the part of the Trustee or any Holder of such Senior
Notes. In the event of a declaration of acceleration because an Event of Default
set forth in Section 6.1(e) above has occurred and is continuing, such
declaration of acceleration shall be automatically rescinded and annulled if the
event of default triggering such Event of Default pursuant to Section 6.1(e)
shall be remedied or cured or waived by the holders of the relevant Indebtedness
within 30 days after such event of default; provided that no judgment or decree
for the payment of the money due on the Senior Notes has been obtained by the
Trustee as provided in this Indenture.

              After any such acceleration, but before a judgment or decree based
on acceleration, the Holders of a majority in aggregate principal amount at
Stated Maturity of the Senior Notes at the time outstanding may rescind and
annul such acceleration if

              (a) the Company or any Guarantor has paid or deposited with the
Trustee a sum sufficient to pay

                  (i) all money paid or advanced by the Trustee hereunder and 
         the reasonable compensation, expenses, disbursement and advances of 
         the Trustee, its agents and counsel,

                  (ii) all overdue installments of interest on any other 
         amounts due in



                                       71




<PAGE>   79



         respect of all Senior Notes;
                  
                  (iii) the principal of (and premium, if any, on ) any Senior 
         Notes that have become due otherwise than by such declaration of
         acceleration and interest thereon at the rate or rates prescribed
         therefor in the Senior Notes and this Indenture; and

                  (iv) to the extent that payment of such interest is lawful, 
         interest upon Defaulted Interest at the rate or rates
         prescribed therefor in the Senior Notes and this Indenture;

              (b) all Events of Default, other than the nonpayment of principal
of Senior Notes which have become due solely by such declaration of
acceleration, have been cured or waived as provided in Section 6.4;

              (c) the annulment of such acceleration would not conflict with any
judgment or decree of a court of competent jurisdiction; and

              (d) the Company has delivered an Officers' Certificate to the
Trustee to the effect of clauses (b) and (c) of this sentence.

              No such rescission shall affect any subsequent Default or impair
any right consequent thereto.

SECTION 6.3.  Other Remedies.

              If an Event of Default occurs and is continuing, the Trustee may
pursue any available remedy to collect the payment of principal (and premium, if
any) of or interest on, and any other amounts then due in respect of, the Senior
Notes or to enforce the performance of any provision of the Senior Notes or this
Indenture.

              The Trustee may maintain a proceeding even if it does not possess
any of the Senior Notes or does not produce any of them in the proceeding. A
delay or omission by the Trustee or any Holder in exercising any right or remedy
accruing upon an Event of Default shall not impair the right or remedy or
constitute a waiver of or acquiescence in the Event of Default. No remedy is
exclusive of any other remedy. All available remedies are cumulative.



                                       72




<PAGE>   80



SECTION 6.4.  Waiver of Past Defaults.

              The Holders of a majority in principal amount at Stated Maturity
of the Senior Notes then outstanding by notice to the Trustee may waive an
existing Default and its consequences except (i) a Default in the payment of the
principal of or interest on a Senior Note or (ii) a Default in respect of a
provision that under Section 9.2 cannot be amended without the consent of each
Holder affected. When a Default is waived, it is deemed cured, but no such
waiver shall extend to any subsequent or other Default or impair any consequent
right.

SECTION 6.5.  Control by Majority.

              The Holders of a majority in principal amount at Stated Maturity
of the Senior Notes then outstanding may direct the time, method and place of
conducting any proceeding for any remedy available to the Trustee or of
exercising any trust or power conferred on the Trustee. However, the Trustee may
refuse to follow any direction that conflicts with law or this Indenture or,
subject to Section 7.1, that the Trustee determines is unduly prejudicial to the
rights of other Holders, it being understood that the Trustee shall have no duty
to ascertain whether or not such actions or forbearances are unduly prejudiced
to such Holders, or would involve the Trustee in personal liability; provided
that the Trustee may take any other action deemed proper by the Trustee that is
not inconsistent with such direction. Prior to taking any action hereunder, the
Trustee shall be entitled to indemnification satisfactory to it in its sole
discretion against all losses and expenses caused by taking or not taking such
action.

SECTION 6.6.  Limitation on Suits.

              No Holder of any Senior Notes shall have any right to institute
any proceeding, judicial or otherwise, with respect to this Indenture, or for
the appointment of a receiver or a trustee, or for any other remedy hereunder,
unless:

                           (i) such Holder has previously given to the Trustee
         written notice of a continuing Event of Default with respect to the
         Senior Notes;

                           (ii) the Holders of at least 25% in aggregate
         principal amount at Stated Maturity of the Senior Notes then
         outstanding have made written request, and such Holder or Holders have
         offered reasonable indemnity, to the Trustee to institute such
         proceeding as trustee; and

                           (iii) the Trustee has failed to institute such
         proceeding, and has not received from the Holders of a majority in
         aggregate principal amount at Stated Maturity of the Senior Notes then
         outstanding a direction inconsistent with such request, within 60 days
         after such notice, request and offer.



                                       73




<PAGE>   81



                  A Holder may not use this Indenture to prejudice the rights of
another Holder or to obtain a preference or priority over another Holder.

SECTION 6.7.  Rights of Holders to Receive Payment.

              Notwithstanding any other provision of this Indenture, the right
of any Holder to receive payment of principal of and interest on the Senior
Notes held by such Holder, on or after the respective due dates expressed in the
Senior Notes, or to bring suit for the enforcement of any such payment on or
after such respective dates, shall not be impaired or affected without the
consent of such Holder.

SECTION 6.8.  Collection Suit by Trustee.

              If an Event of Default specified in Section 6.1(a) or (b) occurs
and is continuing, the Trustee may recover judgment in its own name and as
trustee of an express trust against the Company for the whole amount then due
and owing (together with interest on any unpaid interest to the extent lawful)
and the amounts provided for in Section 7.7.

SECTION 6.9.  Trustee May File Proofs of Claim.

              The Trustee shall be entitled and empowered, without regard to
whether the Trustee or any Holder shall have made any demand or performed any
other act pursuant to the provisions of this Article and without regard to
whether the principal of the Senior Notes shall then be due and payable as
therein expressed or by declaration or otherwise, by intervention in any
proceedings relative to the Company or any Obligor upon the Senior Notes, or to
the creditors or Property or assets of the Company, any Guarantor or any other
Obligor or otherwise, to take any and all actions authorized under the Trust
Indenture Act in order to have claims of the Holders and the Trustee allowed in
any such proceeding. In particular, the Trustee shall be entitled and empowered
in such instances:

              (a) to file and prove a claim or claims for the whole amount of
principal (and premium, if any), interest and any other amounts owing and unpaid
in respect of the Senior Notes, and to file such other papers or documents as
may be necessary or advisable in order to have the claims of the Trustee
(including all amounts owing to the Trustee and each predecessor Trustee
pursuant to Section 7.7 hereof) and of the Holders allowed in any judicial
proceedings relative to the Company or other obligor upon the Senior Notes, or
to the creditors or property of the Company, any Guarantor, or any such other
Obligor,

              (b) unless prohibited by applicable law and regulations, to vote
on behalf of the Holders of the Senior Notes in any election of a trustee or a
standby trustee in arrangement, reorganization, liquidation or other bankruptcy
or insolvency proceedings or Person performing



                                       74




<PAGE>   82



similar functions in comparable proceedings, and

              (c) to collect and receive any moneys or other Property or assets
payable or deliverable on any such claims, and to distribute all amounts
received with respect to the claims of the Holders and of the Trustee on their
behalf; and any trustee, receiver, or liquidator, custodian or other similar
official is hereby authorized by each of the Holders to make payments to the
Trustee, and, in the event that the Trustee shall consent to the making of
payments directly to the Holders, to pay to the Trustee such amounts as shall be
sufficient to cover all amounts owing to the Trustee and each predecessor
Trustee pursuant to Section 7.7.

              Nothing herein contained shall be deemed to authorize the Trustee
to authorize or consent to or vote for or accept or adopt on behalf of any
Holder any plan of reorganization, arrangement, adjustment or composition
affecting the Senior Notes or the rights of any Holder thereof, or to authorize
the Trustee to vote in respect of the claim of any Holder in any such proceeding
except, as aforesaid, to vote for the election of a trustee in bankruptcy or
similar person.

              In any proceedings brought by the Trustee (and also any
proceedings involving the interpretation of any provision of this Indenture to
which the Trustee shall be a party), the Trustee shall be held to represent all
the Holders of the Senior Notes, and it shall not be necessary to make any
Holders of the Senior Notes parties to any such proceedings.

SECTION 6.10.  Priorities.

              If the Trustee collects any money or property pursuant to this
Article 6, it shall pay out the money or property in the following order:

              FIRST: to the Trustee for amounts due under Section 7.7;

              SECOND: to Holders for amounts due and unpaid on the Senior Notes
      for principal and interest, ratably, without preference or priority of any
      kind, according to the amounts due and payable on the Senior Notes for
      principal (premium, if any) and interest, respectively; and

              THIRD: to the Company or the Guarantors or to such other party as
      a court of competent jurisdiction shall direct.

              The Trustee may fix a record date and payment date for any payment
to Holders pursuant to this Section. At least 15 days before such record date,
the Company shall mail to each Holder and the Trustee a notice that states the
record date, the payment date and amount to be paid. The Trustee may mail such
notice in the name and at the expense of the Company.



                                       75




<PAGE>   83



SECTION 6.11.  Undertaking for Costs.

              In any suit for the enforcement of any right or remedy under this
Indenture or in any suit against the Trustee for any action taken or omitted by
it as Trustee, a court in its discretion may require the filing by any party
litigant in the suit of an undertaking to pay the costs of the suit, and the
court in its discretion may assess reasonable costs, including reasonable
attorneys' fees, against any party litigant in the suit, having due regard to
the merits and good faith of the claims or defenses made by the party litigant.
This Section does not apply to a suit by the Trustee, a suit by a Holder
pursuant to Section 6.7 or a suit by Holders of more than 10% in principal
amount at Stated Maturity of the Senior Notes.

SECTION 6.12. Restoration of Rights and Remedies.

              If the Trustee or any Holder of Senior Notes has instituted any
proceeding to enforce any right or remedy under this Indenture and such
proceeding has been discontinued or abandoned for any reason, or has been
determined adversely to the Trustee or to such Holder, then and in every such
case the Company, the Trustee and the Holders shall, subject to any
determination in such proceeding, be restored severally and respectively to
their former positions hereunder, and thereafter all rights and remedies of the
Trustee and the Holders shall continue as though no such proceeding has been
instituted.

SECTION 6.13. Rights and Remedies Cumulative.

              No right or remedy conferred herein, upon or reserved to the
Trustee or to the Holders is intended to be exclusive of any other right or
remedy, and every right and remedy shall, to the extent permitted by law, be
cumulative and in addition to every other right and remedy given hereunder or
now or hereafter existing at law or in equity or otherwise. The assertion or
employment of any right or remedy hereunder, or otherwise, shall not prevent the
concurrent assertion or employment of any other appropriate right or remedy.

SECTION 6.14. Delay or Omission Not Waiver.

              No delay or omission of the Trustee or of any Holder of any Senior
Note to exercise any right or remedy accruing upon any Event of Default shall
impair any such right or remedy or constitute a waiver of any such Event of
Default or an acquiescence therein. Every right and remedy given by this Article
6 or by law to the Trustee or to the Holders may be exercised from time to time,
and as often as may be deemed expedient, by the Trustee or by the Holders, as
the case may be.



                                       76




<PAGE>   84



                                    ARTICLE 7

                                     Trustee

SECTION 7.1.  Duties of Trustee.

              (a) If an Event of Default has occurred and is continuing, the
Trustee shall exercise the rights and powers vested in it by this Indenture and
use the same degree of care and skill in their exercise as a prudent Person
would exercise or use under the circumstances in the conduct of such Person's
own affairs.

              (b) Except during the continuance of an Event of Default:

                  (1)   the Trustee undertakes to perform such duties and only
                        such duties as are specifically set forth in this
                        Indenture and no implied covenants or obligations shall
                        be read into this Indenture against the Trustee; and

                  (2)   in the absence of bad faith on its part, the Trustee may
                        conclusively rely, as to the truth of the statements and
                        the correctness of the opinions expressed therein, upon
                        certificates or opinions furnished to the Trustee and
                        conforming to the requirements of this Indenture.
                        However, the Trustee shall examine the certificates and
                        opinions to determine whether or not they conform to the
                        requirements of this Indenture.

              (c) The Trustee may not be relieved from liability for its own
negligent action, its own negligent failure to act or its own willful
misconduct, except that:

                  (1)   this subsection does not limit the effect of subsection
                        (b) of this Section;

                  (2)   the Trustee shall not be liable for any error of
                        judgment made in good faith by a Trust Officer unless it
                        is proved that the Trustee was negligent in ascertaining
                        the pertinent facts; and

                  (3)   the Trustee shall not be liable with respect to any
                        action it takes or omits to take in good faith in
                        accordance with a direction received by it pursuant to
                        Section 6.5.

              (d) Every provision of this Indenture that in any way relates to
the Trustee is subject to subsections (a), (b) and (c) of this Section.



                                       77




<PAGE>   85



              (e) The Trustee shall not be liable for interest on any money
received by it except as the Trustee may agree in writing with the Company.

              (f) Money held in trust by the Trustee need not be segregated from
other funds except to the extent required by law.

              (g) No provision of this Indenture shall require the Trustee to
expend or risk its own funds or otherwise incur financial liability in the
performance of any of its duties hereunder or in the exercise of any of its
rights or powers, if it shall have reasonable grounds to believe that repayment
of such funds or adequate indemnity against such risk or liability is not
reasonably assured to it.

              (h) Every provision of this Indenture relating to the conduct or
affecting the liability of or affording protection to the Trustee shall be
subject to the provisions of this Section and to the provisions of the Trust
Indenture Act.

SECTION 7.2. Rights of Trustee.

              (a) Subject to the provisions of Section 7.1(a) hereof, the
Trustee may rely on any document believed by it to be genuine and to have been
signed or presented by the proper Person. The Trustee need not investigate any
fact or matter stated in the document.

              (b) Before the Trustee acts or refrains from acting, it may
require an Officers' Certificate or an Opinion of Counsel. The Trustee shall not
be liable for any action it takes or omits to take in good faith in reliance on
the Officers' Certificate or Opinion of Counsel.

              (c) The Trustee may act through agents and shall not be
responsible for the misconduct or negligence of any agent appointed with due
care.

              (d) The Trustee shall not be liable for any action it takes or
omits to take in good faith which it believes to be authorized or within its
rights or powers; provided, however, that the Trustee's conduct does not
constitute willful misconduct or negligence.

              (e) The Trustee may consult with counsel, and the advice or
opinion of counsel with respect to legal matters relating to this Indenture and
the Senior Notes shall be full and complete authorization and protection from
liability in respect to any action taken, omitted or suffered by it hereunder in
good faith and in accordance with the advice or opinion of such counsel.

              (f) Prior to the occurrence of an Event of Default hereunder and
after the curing or waiving of all Events of Default, the Trustee shall not be
bound to make any investigation into the facts or matters stated in any
resolution, Officer's Certificate, or other certificate, statement, instrument,
opinion, report, notice, request, consent, order, approval, appraisal, bond,
debenture,



                                       78




<PAGE>   86



note, coupon, security, or other paper or document unless requested in writing
to do so by the Holders of not less than a majority in aggregate principal
amount of the Senior Notes then outstanding; provided that if the payment within
a reasonable time to the Trustee of the costs, expenses or liabilities likely to
be incurred by it in the making of such investigation is, in the opinion of the
Trustee, not reasonably assured to the Trustee by the security afforded to it by
the terms of this Indenture, the Trustee may require reasonable indemnity
against such expenses or liabilities as a condition to proceeding; the
reasonable expenses of every such examination shall be paid by the Company or,
if advanced by the Trustee, shall be repaid by the Company upon demand.

              (g) The Trustee shall not be required to give any bond or surety
in respect of the performance of its powers and duties hereunder.

              (h) The Trustee shall not be bound to ascertain or inquire as to
the performance or observance of any covenants, conditions, or agreements on the
part of the Company, except as otherwise set forth herein, but the Trustee may
require of the Company full information and advice as to the performance of the
covenants, conditions and agreements contained herein and shall be entitled in
connection herewith to examine the books, records and premises of the Company.

              (i) The permissive rights of the Trustee to do things enumerated
in this Indenture shall not be construed as a duty.

              (j) Except for (i) a default under Section 6.1(a) or (b), or (ii)
any other event of which the Trustee has "actual knowledge" and which event,
with the giving of notice or the passage of time or both, would constitute an
Event of Default under this Indenture, the Trustee shall not be deemed to have
notice of any Default or Event of Default unless specifically notified in
writing of such event by the Company or the Holders of not less than 25% in
aggregate principal amount at Stated Maturity of the Senior Notes then
outstanding; provided that the Trustee shall comply with the "automatic stay"
provisions contained in the U.S. bankruptcy laws, if applicable; and as used
herein, the term "actual knowledge" means the actual fact or statement of
knowing by a Responsible Officer, without any duty to make any investigation
with regard thereto.

SECTION 7.3. Individual Rights of Trustee.

              The Trustee in its individual or any other capacity may become the
owner or pledgee of Senior Notes and may otherwise deal with the Company or its
Affiliates with the same rights it would have if it were not Trustee. Any Paying
Agent, Registrar, co-registrar or co-paying agent may do the same with like
rights. However, the Trustee must comply with Sections 7.10 and 7.11.



                                       79




<PAGE>   87



SECTION 7.4. Trustee's Disclaimer.

              The Trustee shall not be responsible for and makes no
representation as to the validity or adequacy of this Indenture or the Senior
Notes, it shall not be accountable for the Company's use of the proceeds from
the Senior Notes, and it shall not be responsible for any statement of the
Company in this Indenture or in any document issued in connection with the sale
of the Senior Notes or in the Senior Notes other than the Trustee's certificate
of authentication.

SECTION 7.5.  Notice of Defaults.

              If a Default occurs and is continuing and if it is known to the
Trustee, the Trustee shall mail to each Holder notice of the Default within 90
days after it occurs. Except in the case of a Default in payment of principal of
(or premium, if any) or interest on any Senior Note (including payments pursuant
to the mandatory repurchase provisions of such Senior Note, if any), the Trustee
may withhold the notice if and so long as the Trustee in good faith determines
that withholding the notice is in the interests of Holders.

SECTION 7.6.  Reports by Trustee to Holders.

              As promptly as practicable after May 15 beginning with the May 15
following the date of this Indenture, and in any event prior to August 15 in
each year, the Trustee shall mail to each Holder a brief report dated as of such
date that complies with TIA Section 313(a) if and to the extent required by TIA
Section 313(a). The Trustee also shall comply with TIA Sections 313(b) and
313(c).

              A copy of each report at the time of its mailing to Holders shall
be filed with the Commission and each stock exchange (if any) on which the
Senior Notes are listed. The Company agrees to notify promptly the Trustee
whenever the Senior Notes become listed on any stock exchange and of any
delisting thereof.



                                       80




<PAGE>   88



SECTION 7.7.  Compensation and Indemnity.

              The Company shall pay to the Trustee promptly upon request from
time to time the compensation for its services as agreed to by the Trustee and
the Company. The Trustee's compensation shall not be limited by any law on
compensation of a trustee of an express trust. The Company shall reimburse the
Trustee promptly upon request for all reasonable out-of-pocket expenses incurred
or made by it, including costs of collection, in addition to the compensation
for its services. Such expenses shall include the reasonable compensation and
expenses, disbursements and advances of the Trustee's agents, counsel,
accountants and experts. The Company shall indemnify the Trustee against any and
all loss, liability or reasonable expense (including reasonable attorneys' fees)
incurred by it in connection with the acceptance and administration of this
trust and the performance of its duties hereunder. The Trustee shall notify the
Company promptly of any claim for which it may seek indemnity. Failure by the
Trustee to so notify the Company shall not relieve the Company of its
obligations hereunder. The Company shall defend the claim and the Trustee may
have separate counsel and the Company shall pay the fees and expenses of such
counsel. The Company need not reimburse any expense or indemnify against any
loss, liability or expense incurred by the Trustee through the Trustee's own
willful misconduct, negligence or bad faith. The Company need not pay for any
settlement made by the Trustee without the Company's consent, such consent not
to be unreasonably withheld.

              To secure the Company's payment obligations in this Section, the
Trustee shall have a Lien prior to the Senior Notes on all money or property
held or collected by the Trustee other than money or property held in trust to
pay principal of and interest on particular Senior Notes.

              The Company's payment obligations pursuant to this Section shall
survive the discharge of this Indenture. When the Trustee incurs expenses after
the occurrence of a Default specified in Section 6.1(g) or (h) with respect to
the Company, the expenses are intended to constitute expenses of administration
under any applicable bankruptcy laws.

SECTION 7.8.  Replacement of Trustee.

              The Trustee may resign at any time by so notifying the Company.
The Holders of a majority in principal amount at Stated Maturity of the Senior
Notes may remove the Trustee by so notifying the Trustee and may appoint a
successor Trustee. If at any time:

                           (i) the Trustee shall fail to comply with Section
         310(b) of the Trust Indenture Act after written request thereof by the
         Company or by any Holder who has been a bona fide Holder of a Senior
         Note for at least six months, unless the Trustee's duty to resign is
         stayed in accordance with the provisions of TIA Section 310(b); or

                           (ii) the Trustee shall cease to be eligible under
         Section 7.10 hereof and



                                       81




<PAGE>   89



         shall fail to resign after written request therefor by the Company or 
         by any Holder; or

                           (iii) the Trustee shall become incapable of acting or
         a decree or order for relief by a court having jurisdiction in the
         premises shall have been entered in respect of the Trustee in an
         involuntary case under the United States bankruptcy laws, as now or
         hereafter constituted, or any other applicable federal or state
         bankruptcy, insolvency or similar law, or a decree or order by a court
         having jurisdiction in the premises shall have been entered for the
         appointment of a receiver, custodian, liquidator, assignee, trustee,
         sequestrator (or other similar official) of the Trustee or of its
         Property and assets or affairs, or any public officer shall take charge
         or control of the Trustee or of its Property and assets or affairs for
         the purpose of rehabilitation, conservation, winding-up or liquidation;
         or

                           (iv) the Trustee shall commence a voluntary case
         under the United States bankruptcy laws, as now or hereafter
         constituted, or any other applicable federal or state bankruptcy,
         insolvency or similar law or shall consent to the appointment of or
         taking possession by a receiver, custodian, liquidator, assignee,
         trustee, sequestrator (or other similar official) of the Trustee or of
         its Property and assets or affairs, or shall make an assignment for the
         benefit of creditors, or shall admit in writing its inability to pay
         its debts generally as they become due, or shall take corporate action
         in furtherance of any such action,

then, in any such case, (i) the Company by a Board Resolution may remove the
Trustee with respect to the Senior Notes, or (ii) subject to Section 6.11
hereof, any Holder who has been a bona fide Holder of a Note for at least six
months may, on behalf of such Holder and all others similarly situated, petition
any court of competent jurisdiction for the removal of the Trustee and the
appointment of a successor Trustee for the Senior Notes.

              If the Trustee resigns, is removed by the Company or by the
Holders of a majority in principal amount at Stated Maturity of the Senior Notes
and such Holders do not reasonably promptly appoint a successor Trustee, or if a
vacancy exists in the office of Trustee for any reason (the Trustee in such
event being referred to herein as the retiring Trustee), the Company shall
promptly appoint a successor Trustee.

              A successor Trustee shall deliver a written acceptance of its
appointment to the retiring Trustee and to the Company. Thereupon the
resignation or removal of the retiring Trustee shall become effective, and the
successor Trustee shall have all the rights, powers and duties of the Trustee
under this Indenture. The successor Trustee shall mail a notice of its
succession to Holders. The retiring Trustee shall promptly transfer all property
held by it as Trustee to the successor Trustee, subject to the Lien provided for
in Section 7.7.

              If a successor Trustee does not take office within 60 days after 
the retiring Trustee



                                       82




<PAGE>   90



resigns or is removed, the retiring Trustee or the Holders of 10% in principal
amount at Stated Maturity of the Senior Notes may petition any court of
competent jurisdiction for the appointment of a successor Trustee.

              If the Trustee fails to comply with Section 7.10, any Holder may
petition any court of competent jurisdiction for the removal of the Trustee and
the appointment of a successor Trustee.

              Notwithstanding the replacement of the Trustee pursuant to this
Section, the Company's obligations under Section 7.7 shall continue for the
benefit of the retiring Trustee.

SECTION 7.9.  Successor Trustee by Merger.

              If the Trustee consolidates with, merges or converts into, or
transfers all or substantially all its corporate trust business or assets to,
another corporation or banking association, the resulting, surviving or
transferee corporation without any further act shall be the successor Trustee.

              In case at the time such successor or successors by merger,
conversion or consolidation to the Trustee shall succeed to the trusts created
by this Indenture any of the Senior Notes shall have been authenticated but not
delivered, any such successor to the Trustee may adopt the certificate of
authentication of any predecessor trustee, and deliver such Senior Notes so
authenticated; and in case at that time any of the Senior Notes shall not have
been authenticated, any successor to the Trustee may authenticate such Senior
Notes either in the name of any predecessor hereunder or in the name of the
successor to the Trustee; and in all such cases such certificates shall have the
full force which it is anywhere in the Senior Notes or in this Indenture
provided that the certificate of the Trustee shall have.

SECTION 7.10. Eligibility; Disqualification.

              The Trustee shall at all times satisfy the requirements of TIA
Section 310(a). The Trustee shall have a combined capital and surplus of at
least $100,000,000 as set forth in its most recent published annual report of
condition. The Trustee shall comply with TIA Section 310(b); provided, however,
that there shall be excluded from the operation of TIA Section 310(b)(1) any
indenture or indentures under which other securities or certificates of interest
or participation in other securities of the Company are outstanding if the
requirements for such exclusion set forth in TIA Section 310(b)(1) are met.



                                       83




<PAGE>   91



SECTION 7.11. Preferential Collection of Claims Against Company.

              The Trustee shall comply with TIA Section 311(a), excluding any
creditor relationship listed in TIA Section 311(b). A Trustee who has resigned
or been removed shall be subject to TIA Section 311(a) to the extent indicated
therein.

                                    ARTICLE 8

                           Satisfaction and Discharge

SECTION 8.1.  Satisfaction and Discharge.

              This Indenture shall upon the request of the Company cease to be
of further effect (except as to surviving rights of registration of transfer or
exchange of Senior Notes herein expressly provided for, the Company's
obligations under Sections 7.7 and 8.4 hereof, and the Company's, the Trustee's
and the Paying Agent's obligations under Section 8.3 hereof) and the Trustee, at
the expense of the Company, shall execute proper instruments acknowledging
satisfaction and discharge of this Indenture when

                  (a)      either

                           (i) all Senior Notes therefore authenticated and
         delivered (other than (A) Senior Notes which have been destroyed, lost
         or stolen and which have been replaced or paid as provided in Section
         2.8 and (B) Senior Notes for whose payment money has been deposited in
         trust with the Trustee or any Paying Agent and thereafter paid to the
         Company or discharged from such trust) have been delivered to the
         Trustee for cancellation; or

                           (ii) all such Senior Notes not theretofore delivered 
         to the Trustee for cancellation

                           (A)  have become due and payable, or

                           (B)  will become due and payable at their Stated
                  Maturity within one year, or

                           (C)  are to be called for redemption within one year
                  under irrevocable arrangements satisfactory to the Trustee for
                  the giving of notice of redemption by the Trustee in the name,
                  and at the expense, of the Company,

         and the Company, in the case of clause (A), (B) or (C) above, has
         irrevocably deposited or caused to be deposited with the Trustee as
         trust funds in trust for such purpose money or U.S. Government
         Obligations in an amount sufficient (as certified by an independent
         public



                                       84




<PAGE>   92



         accountant designated by the Company) to pay and discharge the entire
         indebtedness of such Senior Notes not theretofore delivered to the
         Trustee for cancellation, for principal (and premium, if any, on) and
         interest, if any, to the date of such deposit (in the case of Senior
         Notes which have become due and payable) or the Stated Maturity or
         Redemption Date, as the case may be;

                  (b) the Company has paid or caused to be paid all other sums
then due and payable hereunder by the Company;

                  (c) no Default or Event of Default with respect to the Senior
Notes shall have occurred and be continuing on the date of such deposit and
after giving effect to such deposit; and

                  (d) the Company has delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent herein provided for relating to the satisfaction and discharge of this
Indenture have been complied with.

                  Notwithstanding the satisfaction and discharge of this
Indenture, the Company's obligations in Sections 2.3, 2.4, 2.6, 2.8, 2.11, 7.7,
7.8, 8.2, 8.3 and 8.4, and the Trustee's and Paying Agent's obligations in
Section 8.3 shall survive until the Senior Notes are no longer outstanding.
Thereafter, only the Company's obligations in Sections 7.7, 8.3 and 8.4 and the
Trustee's and Paying Agent's obligations in Section 8.3 shall survive.

                  In order to have money available on a payment date to pay
principal (and premium, if any, on) or interest on the Senior Notes, the U.S.
Government Obligations shall be payable as to principal (and premium, if any) or
interest at least one Business Day before such payment date in such amounts as
will provide the necessary money. U.S. Government Obligations shall not be
callable at the issuer's option.

SECTION 8.2.  Application of Trust Money.

              All money deposited with the Trustee pursuant to Section 8.1 shall
be held in trust and, at the written direction of the Company, be invested prior
to maturity in U.S. Government Obligations, and applied by the Trustee in
accordance with the provisions of the Senior Notes and this Indenture, to the
payment, either directly or through any Paying Agent as the Trustee may
determine, to the Persons entitled thereto, of the principal (and premium, if
any) and interest for the payment of which money has been deposited with the
Trustee; but such money need not be segregated from other funds except to the
extent required by law.



                                       85




<PAGE>   93



SECTION 8.3.  Repayment to the Company.

              The Trustee and the Paying Agent shall promptly pay to the Company
upon written request any excess money or securities held by them at any time.

              The Trustee and the Paying Agent shall pay to the Company upon
written request any money held by them for the payment of principal or interest
that remains unclaimed for two years after the date upon which such payment
shall have become due; provided that the Company shall have either caused notice
of such payment to be mailed to each Senior Noteholder entitled thereto no less
than 30 days prior to such repayment or within such period shall have published
such notice in a financial newspaper of widespread circulation published in The
City of New York, including, without limitation, The Wall Street Journal. After
payment to the Company, Holders entitled to the money must look to the Company
for payment as general creditors unless an applicable abandoned property law
designates another Person, and all liability of the Trustee and such Paying
Agent with respect to such money shall cease.

SECTION 8.4.  Reinstatement.

              If the Trustee or Paying Agent is unable to apply any money or
U.S. Government Obligations in accordance with Section 8.1 by reason of any
legal proceeding or by reason of any order or judgment of any court of
governmental authority enjoining, restraining or otherwise prohibiting such
application, the Company's and Guarantors' obligations under this Indenture, the
Senior Notes and the Guarantees shall be revived and reinstated as though no
deposit has occurred pursuant to Section 8.1 until such time as the Trustee or
Paying Agent is permitted to apply all such money or U.S. Government Obligations
in accordance with Section 8.2; provided, however, that if the Company or the
Guarantors have made any payment of interest on or principal of any Senior Notes
because of the reinstatement of their Obligations, the Company or such
Guarantors shall be subrogated to the rights of the Holders of such Senior Notes
to receive such payment from the money or U.S. Government Obligations held by
the Trustee or Paying Agent.

                                    ARTICLE 9

                                   Defeasance

SECTION 9.1.  Company's Option to Effect Defeasance or Covenant Defeasance.

              The Company may elect, at its option, at any time, to have Section
9.2 or Section 9.3 hereof applied to the outstanding Senior Notes (in whole and
not in part) upon compliance with the conditions set forth below in this Article
9, such election to be evidenced by a Board Resolution delivered to the Trustee.



                                       86




<PAGE>   94



SECTION 9.2.  Defeasance and Discharge.

              Upon the Company's exercise of its option to have this Section 9.2
applied to the outstanding Senior Notes (in whole and not in part), the Company
shall be deemed to have been discharged from its Obligations with respect to
such Senior Notes as provided in this Section 9.2 on and after the date on which
the conditions set forth in Section 9.4 hereof are satisfied (hereinafter called
"Defeasance"). For this purpose, Defeasance means that the Company shall be
deemed to have paid and discharged the entire indebtedness represented by such
Senior Notes and the Company and the Guarantors shall be deemed to have
satisfied all of their other obligations under such Senior Notes, this Indenture
and the Guarantees (and the Trustee, at the expense of the Company, shall
execute proper instruments acknowledging the same), subject to the following
which shall survive until otherwise terminated or discharged hereunder:

              (a) the rights of Holders of such Senior Notes to receive, solely
from the trust fund described in Section 9.4 hereof and as more fully set forth
in Section 9.4, payments in respect of the principal of and any premium and
interest on such Senior Notes when payments are due,

              (b) the Company's obligations with respect to such Senior Notes
under Sections 2.6, 2.8, 4.17, 4.18 and 4.19 hereof,

              (c) the rights, powers, trusts, duties and immunities of the
Trustee under this Indenture,

              (d) Article 3 hereof, and

              (e) this Article 9.

              Subject to compliance with this Article 9, the Company may
exercise its option to have this Section 9.2 applied to the outstanding Senior
Notes notwithstanding the prior exercise of its option to have Section 9.3
hereof applied to such Senior Notes.



                                       87




<PAGE>   95



SECTION 9.3.  Covenant Defeasance.

              Upon the Company's exercise of its option to have this Section 9.3
applied to the outstanding Senior Notes (in whole and not in part), (i) the
Company and the Guarantors shall be released from their respective obligations
under Sections 5.1 and 5.2, Sections 4.2 through 4.14, inclusive, Sections 4.20,
4.21 and 4.22 and any covenant added to this Indenture subsequent to the Issue
Date pursuant to Section 10.1 hereof, and (ii) the occurrence of any event
specified in Section 6.1(c) or 6.1(d) hereof, with respect to any of Section 5.1
and 5.2, Sections 4.3 through 4.14, inclusive, Sections 4.20, 4.21 and 4.22, and
any covenant added to this Indenture subsequent to the Issue Date pursuant to
Section 10.1 hereof, shall be deemed not to be or result in an Event of Default,
in each case with respect to such Senior Notes as provided in this Section 9.3
on and after the date on which the conditions set forth in Section 9.4 hereof
are satisfied (hereinafter called "Covenant Defeasance"). For this purpose,
Covenant Defeasance means that, with respect to such Senior Notes, the Company
and the Guarantors may omit to comply with and shall have no liability in
respect of any term, condition or limitation set forth in any such specified
Section (to the extent so specified in the case of Section 6.1(c) and 6.1(d)
hereof), whether directly or indirectly by reason of any reference elsewhere
herein to any such Section or by reason of any reference in any such Section to
any other provisions herein or in any other document; but the remainder of this
Indenture, the Guarantees and such Senior Notes shall be unaffected thereby.

SECTION 9.4.  Conditions to Defeasance or Covenant Defeasance.

              The following shall be the conditions to the application of
Section 9.3 or Section 9.4 hereof to the outstanding Senior Notes:

              (a) The Company shall irrevocably have deposited or caused to be
deposited with the Trustee as trust funds in trust for the purpose of making the
following payments, specifically pledged as security for, and dedicated solely
to the benefits of the Holders of such Senior Notes, (i) money in an amount, or
(ii) U.S. Government Obligations which through the scheduled payment of
principal and interest in respect thereof in accordance with their terms will
provide, not later than one Business Day before the due date of any payment,
money in an amount, or (iii) a combination thereof, in each case sufficient, in
the opinion of a nationally recognized firm of independent public accountants
expressed in a written certification thereof delivered to the Trustee, to pay
and discharge the principal of (premium, if any on) and any installment of
interest on such Senior Notes on the Stated Maturity thereof, in accordance with
the terms of this Indenture and such Senior Notes.

              (b) In the event of an election to have Section 9.2 hereof apply
to the outstanding Senior Notes, the Company shall have delivered to the Trustee
an Opinion of Counsel stating that (i) the Company has received from, or there
has been published by, the Internal Revenue Service a ruling or (ii) since the
date of this Indenture, there has been a change in the applicable United States
federal income tax law, in either case (i) or (ii) to the effect that, and based
thereon such opinion



                                       88




<PAGE>   96



shall confirm that, the Holders of such Senior Notes will not recognize gain or
loss for United States federal income tax purposes as a result of the deposit,
Defeasance and discharge to be effected with respect to such Senior Notes and
will be subject to United States federal income tax in the same amount, in the
same manner and at the same times as would be the case if such deposit,
Defeasance and discharge were not to occur.

              (c) In the event of an election to have Section 9.3 hereof apply
to the outstanding Senior Notes, the Company shall have delivered to the Trustee
an Opinion of Counsel to the effect that the Holders of such Senior Notes will
not recognize gain or loss for United States federal income tax purposes as a
result of the deposit and Covenant Defeasance to be effected with respect to
such Senior Notes and will be subject to United States federal income tax in the
same amount, in the same manner and at the same times as would be the case if
such deposit, Covenant Defeasance and discharge were not to occur.

              (d) No Default or Event of Default with respect to the outstanding
Senior Notes shall have occurred and be continuing at the time of such deposit
after giving effect thereto or and no Default or Event of Default under Section
6.1(g) or 6.1(h) shall have occurred at any time on or prior to the 91st day
after the date of such deposit and be continuing on such 91st day (it being
understood that this condition shall not be deemed satisfied until after such
91st day).

              (e) Such Defeasance or Covenant Defeasance shall not cause the
Trustee to have a conflicting interest within the meaning of the Trust Indenture
Act (assuming for the purpose of this clause (e) that all Senior Notes are in
default within the meaning of such Act).

              (f) Such Defeasance or Covenant Defeasance shall not result in a
breach or violation of, or constitute a default under, any other agreement or
instrument to which the Company or the Guarantor is a party or by which it is
bound.

              (g) Such Defeasance or Covenant Defeasance shall not result in the
trust arising from such deposit constituting an investment company within the
meaning of the Investment Company Act of 1940, as amended, unless such trust
shall be registered under such Act or exempt from registration thereunder.

              (h) The Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent with respect to such Defeasance or Covenant Defeasance have been
complied with.



                                       89




<PAGE>   97



SECTION 9.5. Deposited Money and U. S. Government Obligations to be Held in
Trust; Miscellaneous Provisions.

              Subject to Section 9.6 hereof, all money and U.S. Government
Obligations (including the proceeds thereof) deposited with the Trustee pursuant
to Section 9.4 hereof in respect of the outstanding Senior Notes shall be held
in trust and applied by the Trustee, in accordance with the provisions of such
Senior Notes and this Indenture, to the payment, either directly or through any
such Paying Agent as the Trustee may determine, to the Holders of such Senior
Notes, of all sums due and to become due thereon in respect of principal and any
premium and interest, but money so held in trust need not be segregated upon
other funds except to the extent required by law. The Company shall pay and
indemnity the Trustee against any tax, fee or other charge imposed on or
assessed against the U.S. Government Obligations deposited pursuant to Section
9.4 hereof or the principal and interest received in respect thereof other than
such tax, fee or other charge imposed on or assessed against the U.S. Government
Obligations deposited pursuant to Section 9.4 hereof or the principal and
interest received in respect thereof other than any such tax, fee or other
charge which by law is for the account of the Holders of outstanding Senior
Notes.

              Anything in this Article 9 to the contrary notwithstanding, the
Trustee shall deliver or pay to the Company from time to time upon Company Order
any money or U.S. Government Obligations held by it as provided in Section 9.4
hereof which, in the opinion of a nationally recognized firm of independent
public accountants expressed in a written certification thereof delivered to the
Trustee, are in excess of the amount thereof that would then be required to be
deposited to effect the Defeasance or Covenant Defeasance, as the case may be,
with respect to the outstanding Senior Notes.

SECTION 9.6.  Repayment to Company.

              Any money deposited with the Trustee or any Paying Agent, or then
held by the Company, in trust for the payment of the principal of, premium, if
any, or interest, if any, on any Senior Note and remaining unclaimed for two
years after such principal, premium, if any, or interest, if any, have become
due and payable shall be paid to the Company on its request or (if then held by
the Company) shall be discharged from such trust; and the Holder of such Senior
Note shall thereafter, as an unsecured general creditor, look only to the
Company for payment thereof, and all liability of the Company as trustee
thereof, shall thereupon cease; provided that the Trustee or such Paying Agent,
before being required to make any such repayment, may at the expense of the
Company cause to be published once, in the New York Times and The Wall Street
Journal (national edition), notice that such money remains unclaimed and that,
after a date specified therein, which shall not be less than 30 days from the
date of such notification or publication, any unclaimed balance of such money
then remaining will be repaid to the Company.



                                       90




<PAGE>   98



SECTION 9.7.  Reinstatement.

              If the Trustee or Paying Agent is unable to apply any money in
accordance with this Article 9 with respect to any Notes by reason of any order
or judgment of any court or governmental authority enjoining, restraining or
otherwise prohibiting such application, then the obligations under this
Indenture, the Guarantees and such Senior Notes from which the Company or the
Guarantors have been discharged or released pursuant to Section 9.2 or 9.3
hereof shall be revived and reinstated as though no deposit had occurred
pursuant to this Article 9 with respect to such Senior Notes, until such time as
the Trustee or Paying Agent is permitted to apply all money held in trust
pursuant to Section 9.5 hereof with respect to such Senior Notes in accordance
with this Article 9; provided that if the Company or any Guarantor makes any
payment of principal of, premium, if any, or interest on any such Senior Note
following such reinstatement of its obligations, the Company or such Guarantor,
as the case may be, shall be subrogated to the Holders of such Senior Notes to
receive such payment from the money so held in trust.

                                   ARTICLE 10

                                   Amendments

SECTION 10.1.  Without Consent of Holders.

              (a) The Company, the Guarantors and the Trustee may at any time
and from time to time, without notice to or consent of any Holder, enter into
one or more indentures supplemental hereto, in form satisfactory to the Trustee,
for any of the following purposes:

                  (i) to evidence the succession of another Person to the 
         Company and the Guarantors and the assumption by such successor of
         the covenants and Obligations of the Company under this Indenture and
         contained in the Senior Notes and the Guarantors contained in this
         Indenture and the Guarantees;

                  (ii) to add to the covenants of the Company, for the 
         benefit of the Holders, or to surrender any right or power conferred
         upon the Company or the Guarantors by this Indenture;

                  (iii) to add any additional Events of Default;

                  (iv)  to provide for uncertificated Senior Notes in addition 
         to or in place of Certificated Senior Notes;

                  (v)  to evidence and provide for the acceptance of 
         appointment under this Indenture by the successor Trustee;



                                       91




<PAGE>   99



                    (vi)  to secure the Senior Notes and/or the Guarantees;

                    (vii) to cure any ambiguity, to correct or supplement
         any provision in this Indenture which may be inconsistent with any
         other provision therein or to add any other provisions with respect to
         matters or questions arising under this Indenture, provided that such
         actions will not adversely affect the interests of the Holders in any
         material respect; or

                    (viii) to add or release any Guarantor pursuant to the 
         terms of this Indenture.

SECTION 10.2.  With Consent of Holders.

              With the consent of the Holders of at least a majority of the
principal amount at Stated Maturity of the outstanding Senior Notes (including
consents obtained in connection with a tender offer or an exchange offer for the
Senior Notes), by Act delivered to the Company, the Guarantors and the Trustee,
the Company, the Guarantors and the Trustee may enter into one or more
indentures supplemental hereto for the purpose of adding any provisions to or
changing or eliminating any of the provisions of this Indenture or modifying the
rights of the Holders of the Senior Notes, provided that no such supplemental
indenture, without the consent of the Holder of each outstanding Senior Note
affected thereby, will:

              (a) change the Stated Maturity of the principal of, or any
installment of interest on, any Senior Note, or reduce the principal amount
thereof (or any premium, if any), or the interest thereon, that would be due and
payable upon Maturity thereof, or change the place of payment where, or the coin
or currency in which, any Senior Note or any premium or interest thereon is
payable, or impair the right to institute suit for the enforcement of any such
payment on or after the Stated Maturity thereof; or

              (b) reduce the percentage in principal amount at Stated Maturity
of the outstanding Senior Notes, the consent of whose Holders is required for
any such supplemental indenture or required for any waiver of compliance with
the provisions of this Indenture; or

              (c) modify any of the provisions of Section 6.4 hereof, except to
increase the percentage set forth therein or to provide that certain other
provisions of this Indenture cannot be amended or waived without the consent of
the Holder of each outstanding Senior Note affected thereby; or

              (d) subordinate in right of payment, or otherwise subordinate, the
Senior Notes or the Guarantees to any other Indebtedness; or

              (e) modify any provision of this Indenture relating to the
obligations of the Company to make offers to purchase Senior Notes upon a Change
of Control or from the proceeds



                                       92




<PAGE>   100



of an Asset Sale; or

              (f) modify any of the provisions of this Section 10.2 except to
increase any percentage set forth herein or to provide that certain other
provisions of this Indenture cannot be modified or waived without the consent of
the Holders of each outstanding Senior Note affected thereby; or

              (g) amend, supplement or otherwise modify the provisions of this
Indenture relating to the Guarantees.

              It shall not be necessary for any Act of Holders under this
Section 10.2 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such Act shall approve the substance
thereof.

SECTION 10.3.  Effect of Supplemental Indentures.

              Upon the execution of any supplemental indenture under this
Article 10, this Indenture shall be modified in accordance therewith, and such
supplemental indenture shall form a part of this Indenture for all purposes; and
every Holder of Senior Notes theretofore or thereafter authenticated and
delivered hereunder shall be bound thereby. After a supplemental indenture
becomes effective, the Company shall mail to Holders a notice briefly describing
such amendment. The failure to give such notice to all Holders, or any defect
therein, shall not impair or affect the validity of an amendment under this
Section.

SECTION 10.4.  Compliance with Trust Indenture Act.

              Every amendment to this Indenture or the Senior Notes shall comply
with the Trust Indenture Act as then in effect.

SECTION 10.5.  Revocation and Effect of Consents and Waivers.

              (a) A consent to an amendment or a waiver by a Holder of a Senior
Note shall bind the Holder and every subsequent Holder of that Senior Note or
portion of the Senior Note that evidences the same debt as the consenting
Holder's Senior Note, even if notation of the consent or waiver is not made on
the Senior Note. However, any such Holder or subsequent Holder may revoke the
consent or waiver as to such Holder's Senior Note or portion of the Senior Note
if the Trustee receives the notice of revocation before the date the amendment
or waiver becomes effective. After an amendment or waiver becomes effective, it
shall bind every Holder. An amendment or waiver becomes effective upon the
execution of a supplemental indenture containing such amendment or waiver by the
Trustee.

              (b) The Company may, but shall not be obligated to, fix a record
date for the



                                       93




<PAGE>   101



purpose of determining the Holders entitled to give their consent or take any
other action described above or required or permitted to be taken pursuant to
this Indenture. If a record date is fixed, then notwithstanding the immediately
preceding subsection, those Persons who were Holders at such record date (or
their duly designated proxies), and only those Persons, shall be entitled to
give such consent or to revoke any consent previously given or to take any such
action, whether or not such Persons continue to be Holders after such record
date. No such consent shall be valid or effective for more than 120 days after
such record date.

SECTION 10.6. Notation on or Exchange of Senior Notes.

              If an amendment changes the terms of a Senior Note, the Trustee
may require the Holder of the Senior Note to deliver it to the Trustee. The
Trustee may place an appropriate notation on the Senior Note regarding the
changed terms and return it to the Holder. Alternatively, if the Company or the
Trustee so determines, the Company in exchange for the Senior Note shall issue
and the Trustee shall authenticate a new Senior Note that reflects the changed
terms. Failure to make the appropriate notation or to issue a new Senior Note
shall not affect the validity of such amendment.

SECTION 10.7. Trustee To Execute Supplemental Indentures.

              The Trustee shall execute any supplemental indenture authorized
pursuant to this Article 10 if such supplemental indenture does not adversely
affect the rights, duties, liabilities or immunities of the Trustee. If it does,
the Trustee may, but shall not be required to, execute such supplemental
indenture. In executing any supplemental indenture, the Trustee shall be
entitled to receive indemnity reasonably satisfactory to it and to receive, and
(subject to Section 7.1 hereof) shall be fully protected in relying upon, an
Officers' Certificate (which need only cover the matters set forth in clause (a)
below) and an Opinion of Counsel provided by the Company stating that:

              (a) such supplemental indenture is authorized or permitted by this
Indenture and that all conditions precedent to the execution, delivery and
performance of such supplemental indenture have been satisfied:

              (b) the Company and the Guarantors have all necessary corporate
power and authority to execute and deliver the supplemental indenture and that
the execution, delivery and performance of such supplemental indenture has been
duly authorized by all necessary corporate action of the Company and the
Guarantors;

              (c) the execution, delivery and performance of the supplemental
indenture do not conflict with, or result in the breach of or constitute a
default under any of the terms, conditions or provisions of (i) this Indenture,
(ii) the charter documents and by-laws of the Company or any Guarantor, or (iii)
any material agreement or instrument to which the Company or any Guarantor is



                                       94




<PAGE>   102



subject and of which such counsel is aware;

              (d) to the knowledge of legal counsel writing such Opinion of
Counsel, the execution, delivery and performance of the supplemental indenture
do not conflict with, or result in the breach of any of the terms, conditions or
provisions of (i) any law or regulation applicable to the company or any
Guarantor, or (ii) any material order, writ, injunction or decree of any court
or governmental instrumentality applicable to the Company or any Guarantor;

              (e) such supplemental indenture has been duly and validly executed
and delivered by the Company and the Guarantors, and the Indenture together with
such supplemental indenture constitutes a legal, valid and binding obligations
of the Company and the Guarantors enforceable against the Company and the
Guarantors, as applicable, in accordance with its terms, except as such
enforceability may be limited by applicable bankruptcy, insolvency, or similar
laws affecting the enforcement of creditors' rights generally and general
equitable principles; and

              (f) the Indenture together with such amendment or supplement
complies with the Trust Indenture Act.

SECTION 10.8. Payment for Consent.

              Neither the Company nor any Affiliate of the Company shall,
directly or indirectly, pay or cause to be paid any consideration, whether by
way of interest, fee or otherwise, to any Holder for or as an inducement to any
consent, waiver or amendment of any of the terms or provisions of this Indenture
or the Senior Notes unless such consideration is offered to be paid to all
Holders that so consent, waive or agree to amend in the time frame set forth in
solicitation documents relating to such consent, waiver or agreement.



                                       95




<PAGE>   103



                                   ARTICLE 11

                                   Guarantees

SECTION 11.1. Guarantees.

              (a) For good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, each of the Guarantors, hereby
jointly and severally and irrevocably and unconditionally guarantees to the
Trustee and to each Holder of a Senior Note authenticated and delivered by the
Trustee irrespective of the validity or enforceability of this Indenture or the
Senior Notes or the Obligations of the Company and the Guarantors under this
Indenture, that: (i) the principal of, premium, if any, and any interest, on the
Senior Notes (including, without limitation, any interest that accrues after the
filing of a proceeding of the type described in Sections 6.1(g) and (h)) and any
fees, expenses and other amounts owing under this Indenture will be duly and
punctually paid in full when due, whether at Stated Maturity, by acceleration,
call for redemption, upon a Change of Control Offer, Asset Sale Offer, purchase
or otherwise, and interest on the overdue principal and (to the extent permitted
by law) interest, if any, on the Senior Notes and any other amounts due in
respect of the Senior Notes, and all other Obligations of the Company and the
Guarantors to the Holders of the Senior Notes under this Indenture and the
Senior Notes, whether now or hereafter existing, will be promptly paid in full
or performed, all strictly in accordance with the terms hereof and of the Senior
Notes; and (ii) in case of any extension of time of payment or renewal of any
Senior Notes or any of such other Obligations, the same will be promptly paid in
full when due or performed in accordance with the terms of the extension or
renewal, whether at Stated Maturity, by acceleration, call for redemption, upon
Change of Control Offer, Asset Sale Offer, purchase or otherwise. If payment is
not made when due of any amount so guaranteed for whatever reason, each
Guarantor shall be jointly and severally obligated to pay the same individually
whether or not such failure to pay has become an Event of Default which could
cause acceleration pursuant to Sction 6.2. Each Guarantor agrees that this is a
guarantee of payment and not a guarantee of collection. An Event of Default
under this Indenture or the Senior Notes shall constitute an Event of Default
under this Guarantee, and shall entitle the Holders to accelerate the
Obligations of each Guarantor hereunder in the same manner and to the same
extent as the Obligations of the Company. This Guarantee is intended to be
superior to or pari passu in right of payment with all Indebtedness of the
Guarantors and each Guarantor's Obligations are independent of any Obligation of
the Company or any other Guarantor.

              (b) Each Guarantor waives presentation to, demand of, payment from
and protest to the Company of any of the Obligations under this Indenture or the
Senior Notes and also waives notice of protest for nonpayment. Each Guarantor
waives notice of any default under the Senior Notes or the Obligations. The
Obligations of each Guarantor hereunder shall not be affected by (a) the failure
of any Holder or the Trustee to assert any claim or demand or to enforce any
right or remedy against the Company or any other Person under this Indenture,
the Senior Notes or any other



                                       96




<PAGE>   104



agreement or otherwise; (b) any extension or renewal of any thereof; (c) any
rescission, waiver, amendment or modification of any of the terms or provisions
of this Indenture, the Senior Notes or any other agreement; (d) the release of
any security held by any Holder or the Trustee for the Obligations or any of
them; (e) the failure of any Holder or the Trustee to exercise any right or
remedy against any other guarantor of the Obligations; or (f) any change in the
ownership of such Guarantor.

              (c) The Obligations of each Guarantor hereunder shall not be
subject to any reduction, limitation, impairment or termination for any reason,
including any claim of waiver, release, surrender, alteration or compromise, and
shall not be subject to any defense of setoff, counterclaim, recoupment or
termination whatsoever or by reason of the invalidity, illegality or
unenforceability of the Obligations of the Company or otherwise. Without
limiting the generality of the foregoing, the Obligations of each Guarantor
herein shall not be discharged or impaired or otherwise affected by the failure
of any Holder or the Trustee to assert any claim or demand or to enforce any
remedy under this Indenture, the Senior Notes or any other agreement, by any
waiver or modification of any thereof, by any default, failure or delay, willful
or otherwise, in the performance of the Obligations of the Company, or by any
other act or thing or omission or delay to do any other act or thing which may
or might in any manner or to any extent vary the risk of such Guarantor or would
otherwise operate as a discharge of such Guarantor as a matter of law or equity.

              (d) Each Guarantor further agrees that its Guarantee herein shall
continue to be effective or be reinstated, as the case may be, if at any time
payment, or any part thereof, of principal of, premium, if any, on or interest
on any Obligation of the Company is rescinded or must otherwise be restored by
any Holder or the Trustee upon the bankruptcy or reorganization of the Company
or otherwise.

              (e) In furtherance of the foregoing and not in limitation of any
other right which any Holder or the Trustee has at law or in equity against any
Guarantor by virtue hereof, upon the failure of the Company to pay the principal
of, premium, if any, on or interest on any Obligation when and as the same shall
become due, whether at maturity, by acceleration, by redemption or otherwise, or
to perform or comply with any other Obligation, each Guarantor hereby promises
to and will, upon receipt of written demand by the Trustee, forthwith pay, or
cause to be paid, in cash, to the Holders or the Trustee an amount equal to the
sum of (i) the unpaid amount of such Obligations, (ii) accrued and unpaid
interest on such Obligations (but only to the extent not prohibited by law) and
(iii) all other monetary Obligations of the Company to the Holders and the
Trustee.

              (f) Until such time as the Senior Notes and the other Obligations
of the Company guaranteed hereby have been satisfied in full, each Guarantor
hereby irrevocably waives any claim or other rights that it may now or hereafter
acquire against the Company or any other Guarantor that arise from the
existence, payment, performance or enforcement of such Guarantor's Obligations



                                       97




<PAGE>   105



under this Guarantee, including, without limitation, any right of subrogation,
reimbursement, exoneration, contribution or indemnification and any right to
participate in any claim or remedy of the Holders or the Trustee against the
Company or any other Guarantor or any security, whether or not such claim,
remedy or right arises in equity or under contract, statute or common law,
including, without limitation, the right to take or receive from the Company or
any other Guarantor, directly or indirectly, in cash or other property or by
set-off or in any other manner, payment or security on account of such claim,
remedy or right. If any amount shall be paid to such Guarantor in violation of
the preceding sentence at any time prior to the later of the payments in full of
the Senior Notes and all other amounts payable under this Indenture, this
Guarantee and the Stated Maturity of the Notes, such amount shall be held in
trust for the benefit of the Holders and the Trustee and shall forthwith be paid
to the Trustee to be credited and applied to the Notes and all other amounts
payable under this Guarantee, whether matured or unmatured, in accordance with
the terms of this Indenture, or to be held as security for any Obligations or
other amounts payable under this Guarantee thereafter arising.

              (g) Each Guarantor acknowledges that it will receive direct and
indirect benefits from the financing arrangements contemplated by this Indenture
and that the waiver set forth in this Section 11.1 is knowingly made in
contemplation of such benefits. Each Guarantor further agrees that, as between
it, on the one hand, and the Holders and the Trustee, on the other hand, (x)
subject to this Article 11, the maturity of the Obligations guaranteed hereby
may be accelerated as provided in Article 6 for the purposes of this Guarantee,
notwithstanding any stay, injunction or other prohibition preventing such
acceleration in respect of the Obligations guaranteed hereby, and (y) in the
event of any acceleration of such Obligations guaranteed hereby as provided in
Article 6, such Obligations (whether or not due and payable) shall further then
become due and payable by the Guarantors for the purposes of this Guarantee.

              (h) A Guarantor that makes a distribution or payment under a
Guarantee shall be entitled to contribution from each other Guarantor in a pro
rata amount based on the Adjusted Net Assets of each such other Guarantor for
all payments, damages and expenses incurred by that Guarantor in discharging the
Company's obligations with respect to the Senior Notes and this Indenture or any
other Guarantor with respect to its Guarantee, so long as the exercise of such
right does not impair the rights of the Holders of the Senior Notes under the
Guarantees.

              (i) Each Guarantor also agrees to pay any and all costs and
expenses (including reasonable attorneys' fees) incurred by the Trustee or any
Holder in enforcing any rights under this Section.



                                       98




<PAGE>   106



SECTION 11.2. Limitation on Liability.

              Any term or provision of this Indenture to the contrary
notwithstanding, the maximum aggregate amount of the Obligations guaranteed
hereunder by any Guarantor shall not exceed the maximum amount that can be
hereby guaranteed without rendering this Indenture, as it relates to such
Guarantor, void, voidable or unenforceable under applicable law relating to
fraudulent conveyance or fraudulent transfer or similar laws affecting the
rights of creditors generally. To effectuate the foregoing intention, the
Obligations of each Guarantor shall be limited to the maximum amount as will,
after giving effect to all other contingent and fixed liabilities of such
Guarantor and after giving effect to any collections from or payments made by or
on behalf of any other Guarantor in respect of the Obligations of such other
Guarantor under its Guarantee or pursuant to its contribution Obligations
hereunder, result in the Obligations of such Guarantor under its Guarantee not
constituting a fraudulent conveyance or fraudulent transfer under federal, state
or foreign law. Each Guarantor that makes a payment or distribution under a
Guarantee shall be entitled to a contribution from each other Guarantor in a pro
rata amount based on the Adjusted Net Assets of each Guarantor.

SECTION 11.3. Execution and Delivery of Guarantees.

              To further evidence its Guarantee set forth in Section 11.1
hereof, each Guarantor hereby agrees that notation of such Guarantee shall be
endorsed on each Senior Note authenticated and delivered by the Trustee and
executed by either manual or facsimile signature of an authorized officer of
such Guarantor. Each Guarantor hereby agrees that its Guarantee set forth in
Section 11.1 hereof shall remain in full force and effect notwithstanding any
failure to endorse on each Note a notation of such Guarantee. If an officer of a
Guarantor whose signature is on this Indenture or a Senior Note no longer holds
that office at the time the Trustee authenticates such Senior Note or at any
time thereafter, such Guarantor's Guarantee of such Senior Note shall be valid
nevertheless. The delivery of any Senior Note by the Trustee, after the
authentication thereof hereunder, shall constitute due delivery of any Guarantee
set forth in this Indenture on behalf of the Guarantor.



                                       99




<PAGE>   107



SECTION 11.4. When a Guarantor May Merge, etc.

              No Guarantor shall consolidate with or merge with or into (whether
or not such Guarantor is the surviving person) another corporation, Person or
entity whether or not affiliated with such Guarantor (but excluding any
consolidation, amalgamation or merger if the surviving corporation is no longer
a Subsidiary) unless (i) subject to the provisions of Section 11.7 hereof, the
Person formed by or surviving any such consolidation or merger (if other than
such Guarantor) assumes all the Obligations of such Guarantor pursuant to a
supplemental indenture in form reasonably satisfactory to the Trustee under the
Senior Notes and this Indenture and (ii) immediately after giving effect to such
transaction, no Default or Event of Default exists. In connection with any such
consolidation or merger, the Trustee shall be entitled to receive an Officers'
Certificate and an Opinion of Counsel stating that such consolidation or merger
is permitted by this Section 11.4.

SECTION 11.5. No Waiver.

              Neither a failure nor a delay on the part of either the Trustee or
the Holders in exercising any right, power or privilege under this Article 11
shall operate as a waiver thereof, nor shall a single or partial exercise
thereof preclude any other or further exercise of any right, power or privilege.
The rights, remedies and benefits of the Trustee and the Holders herein
expressly specified are cumulative and not exclusive of any other rights,
remedies or benefits which either may have under this Article 11 at law, in
equity, by statute or otherwise.

SECTION 11.6. Modification.

              No modification, amendment or waiver of any provision of this
Article 11, nor the consent to any departure by any Guarantor therefrom, shall
in any event be effective unless the same shall be in writing and signed by the
Trustee, and then such waiver or consent shall be effective only in the specific
instance and for the purpose for which given. No notice to or demand on any
Guarantor in any case shall entitle such Guarantor to any other or further
notice or demand in the same, similar or other circumstances.



                                       100




<PAGE>   108



SECTION 11.7. Release of Guarantor.

              Upon the sale or other transfer of all of the Capital Stock of a
Guarantor to any Person that is not an Affiliate of the Company in compliance
with the terms of this Indenture (including, without limitation, Section 4.7
hereof) and in a transaction that does not result in a Default or an Event of
Default being in existence or continuing immediately thereafter, such Guarantor
shall be deemed automatically and unconditionally released and discharged from
all obligations under this Indenture without any further action required on the
part of the Trustee or any Holder; provided that the Net Available Proceeds of
such sale or other disposition are applied in accordance with Section 4.7 of
this Indenture as if such sale or disposition were an Asset Sale and in
accordance with the applicable provisions of this Indenture. The Trustee shall
deliver at the expense of the Company an appropriate instrument or instruments
evidencing such release upon receipt of a request of the Company accompanied by
an Officers' Certificate and Opinion of Counsel certifying as to the compliance
with this Section 11.7 and the other applicable provisions of this Indenture.

SECTION 11.8. Execution of Supplemental Indentures for Future Guarantors.

              Any Wholly Owned Subsidiary that is a domestic Subsidiary or any
other Subsidiary that guarantees any Indebtedness of an Obligor is required to
become a Guarantor and the Company shall cause each such Subsidiary to promptly
execute and deliver to the Trustee a supplemental indenture in the form of
Exhibit C hereto pursuant to which such Subsidiary shall become a Guarantor
under this Article 11 and shall guarantee the Obligations of the Company under
the Senior Notes and this Indenture. Concurrently with the execution and
delivery of such supplemental indenture, the Company shall deliver to the
Trustee an Opinion of Counsel to the effect that such supplemental indenture has
been duly authorized, executed and delivered by such Subsidiary and that,
subject to the application of bankruptcy, insolvency, moratorium, fraudulent
conveyance or transfer and other similar laws relating to creditors' rights
generally and to the principles of equity, whether considered in a proceeding at
law or in equity, the Guarantee of such Guarantor is a legal, valid and binding
obligation of such Guarantor, enforceable against such Guarantor in accordance
with its terms, and as to any such other matters as the Trustee may reasonably
request.



                                       101




<PAGE>   109



                                   ARTICLE 12

                                  Miscellaneous

SECTION 12.1. Compliance Certificates and Opinions.

              Upon any application or request by the Company or the Guarantors
to the Trustee to take any action under any provision of this Indenture, the
Company and the Guarantors, as applicable, shall furnish to the Trustee, to the
extent required by the TIA or this Indenture, (i) an Officers' Certificate
stating that all conditions precedent, if any, provided for in this Indenture
(including any covenant, compliance with which constitutes a condition
precedent) relating to the proposed action have been complied with and (ii) an
Opinion of Counsel stating that in the opinion of such counsel all such
conditions precedent, if any, have been complied with, except that in the case
of any such application or request as to which the furnishing of such documents
is specifically required by any provision of this Indenture relating to such
particular application or request, no additional certificate or opinion need be
furnished.

              Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include:

              (1)   a statement that each individual signing such certificate or
                    opinion has read such covenant or condition and the
                    definitions herein relating thereto;

              (2)   a brief statement as to the nature and scope of the
                    examination or investigation upon which the statements or
                    opinions contained in such certificate or opinion are based;

              (3)   a statement that, in the opinion of each such individual, he
                    has made such examination or investigation as is necessary
                    to enable him to express an informed opinion as to whether
                    or not such covenant or condition has been complied with;
                    and

              (4)   a statement as to whether or not, in the opinion of each
                    such individual, such condition or covenant has been
                    complied with.



                                       102




<PAGE>   110



SECTION 12.2. Form of Documents Delivered to Trustee.

              In any case where several matters are required to be certified by,
or covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

              Any certificate or opinion of an officer of the Company or any
Guarantor may be based, insofar as it relates to legal matters, upon a
certificate or opinion of, or representations by, counsel, unless such officer
knows, or in the exercise of reasonable care should know, that the certificate
or opinion or representations with respect to the matters upon which his
certificate or opinion is based are erroneous. Any such certificate or opinion
of counsel may be based, and may state that it is so based, insofar as it
relates to factual matters, upon a certificate or opinion of, or representations
by, an officer or officers of the Company or such Guarantor stating that the
information with respect to such factual matters is in the possession of the
Company or such Guarantor, unless such counsel knows, or in the exercise of
reasonable care should know, that the certificate of opinion or representations
with respect to such matters are erroneous.

              Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

SECTION 12.3. Acts of Holders.

              (a) Any request, demand, authorization, direction, notice,
consent, waiver or other action provided by this Indenture to be given or taken
by a specified percentage of Holders may be embodied in and evidenced by one or
more instruments of substantially similar tenor signed by such specified
percentage of Holders in person or by agents duly appointed in writing; and,
except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments are received by the Trustee and,
where it is hereby expressly required, to the Company and the Guarantors. Such
instrument or instruments (and the action embodied therein and evidenced
thereby) are herein sometimes referred to as the "Act" of the Holders signing
such instrument or instruments. Proof of execution of any such instrument or of
a writing appointing any such agent shall be sufficient for any purpose of this
Indenture and (subject to Sections 7.1 and 7.2) conclusive in favor of the
Trustee, the Company and the Guarantors, if made in the manner provided in this
Section.

              (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary



                                       103




<PAGE>   111



public or other officer authorized by law to take acknowledgments of deeds,
certifying that the individual signing such instrument or writing acknowledged
to him the execution thereof. Where such execution is by a signer acting in a
capacity other than his individual capacity, such certificate or affidavit shall
also constitute sufficient proof of authority. The fact and date of the
execution of any such instrument or writing, or the authority of the Person
executing the same, may also be proved in any other manner which the Trustee
deems sufficient, including the execution of such instrument or writing without
more.

              (c) The ownership, principal amount and serial numbers of Senior
Notes held by any Person, and the date of holding the same, shall be proved by
the Senior Note Register.

              (d) If the Company shall solicit from the Holders of Senior Notes
any request, demand, authorization, direction, notice, consent, waiver or other
Act, the Company may, at its option, by or pursuant to Board Resolution, fix in
advance a record date for the determination of Holders entitled to give such
request, demand, authorization, direction, notice, consent, waiver or other Act,
but the Company shall have no obligation to do so. Such record date shall be the
record date specified in or pursuant to such Board Resolution, which shall be a
date not earlier than the date 30 days prior to the first solicitation is
completed. If such a record date is fixed, such request, demand, authorization,
direction, notice, consent, waiver or other Act may be given before or after
such record date, but only the Holders of record at the close of business on
such record date shall be deemed to be Holders for the purposes of determining
whether Holders of the requisite proportion of outstanding Senior Notes have
authorized or agreed or consented to such request, demand, authorization,
direction, notice, consent, waiver or other Act, and for that purpose the
outstanding Senior Notes shall be computed as of such record date; provided that
no such authorization, agreement or consent by the Holders on such record date
shall be deemed effective unless it shall become effective pursuant to the
provisions of this Indenture not later than eleven months after the record date.

              (e) Except to the extent otherwise expressly provided in this
Indenture, any request, demand, authorization, direction, notice, consent,
waiver or other Act of the Holder of any Senior Note shall bind every future
Holder of the same Senior Note and the Holder of every Senior Note issued upon
the registration of transfer thereof or in exchange therefor or in lieu thereof
in respect of anything done, omitted or suffered to be done by the Trustee or
the Company in reliance thereon, whether or not notation of such action is made
upon such Senior Note.

              (f) Without limiting the foregoing, a Holder entitled hereunder to
give or take any action with regard to any particular Senior Note may do so with
regard to all or any part of the principal amount of such Senior Note or by one
or more duly appointed agents each of which may do so pursuant to such
appointment with regard to all or any different part of such principal amount.



                                       104




<PAGE>   112



SECTION 12.4. Trust Indenture Act Controls.

              If any provision of this Indenture limits, qualifies or conflicts
with another provision which is required to be included in this Indenture by
Sections 310 to 318, inclusive, of the Trust Indenture Act, the required
provision shall control. If any provision of this Indenture modifies or excludes
any provision of the TIA that may be so modified or excluded, the latter
provision shall be deemed to apply to this Indenture as so modified or excluded,
as the case may be.



                                       105




<PAGE>   113



SECTION 12.5. Notices.

              Any notice or communication shall be in writing and delivered in
person, or sent by registered or certified mail, by air courier guaranteeing
overnight delivery or by fax (promptly confirmed by telephone) and addressed as
follows:


                  if to the Company or any Guarantor:

                           Grey Wolf, Inc.
                           10370 Richmond Avenue
                           Suite 600
                           Houston, Texas  77042
                           Attn:  Chief Financial Officer
                           Phone: (281) 435-6100
                           Fax:   (281) 435-6171

                  if to the Trustee:

                           Chase Bank of Texas, National Association
                           600 Travis Street, Suite 1150
                           Houston, Texas  77002
                           Attention:  Corporate Trust Division
                           Phone: (713) 216-5811
                           Fax:   (713) 216-5476

                  with a copy to the Trustee's Dallas Payment Office:

                           Chase Bank of Texas, National Association
                           1201 Main Street
                           Dallas, Texas  75202
                           Attn:  Corporate Trust Services

              The Company, the Guarantors or the Trustee by notice to the others
may designate additional or different addresses for subsequent notices or
communications.

              Any notice or communication mailed to a Holder shall be sent to
the Holder by first class mail, postage prepaid, at the Holder's address as it
appears in the Senior Note Register and shall be given if so sent within the
time prescribed. Failure to mail a notice or communications to a Holder or any
default in it shall not affect its sufficiency with respect to other Holders. If
a notice or communication is mailed or faxed to the Company, the Guarantors, the
Trustee or a Holder in the manner provided above, it is duly given, whether or
not the addressee receives it but shall not be



                                       106




<PAGE>   114



effective unless in the case of the Company, the Guarantors or the Trustee
actually received. In case by reason of the suspension of regular mail service
or by reason or any other cause it shall be impracticable to give notice by mail
to Holders, then such notification as shall be made with the approval of the
Trustee shall constitute a sufficient notification for every purpose hereunder.

SECTION 12.6. Communication by Holders with Other Holders.

              Holders may communicate pursuant to TIA Section 312(b) with other
Holders with respect to their rights under this Indenture or the Senior Notes.
The Company, the Guarantors, the Trustee, the Registrar and anyone else shall
have the protection of TIA Section 312(c).

SECTION 12.7. Rules by Trustee, Paying Agent and Registrar.

              The Trustee may make reasonable rules for action by or a meeting
of Holders. The Registrar and the Paying Agent may make reasonable rules for
their functions.

SECTION 12.8. Payments on Business Days.

              If a payment hereunder is scheduled to be made on a date that is
not a Business Day, payment shall be made on the next succeeding day that is a
Business Day, and no interest shall accrue with respect to that payment during
the intervening period. If a regular Record Date is not a Business Day, such
Record Date shall not be affected.

SECTION 12.9. GOVERNING LAW.

              THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

SECTION 12.10. No Recourse Against Others.

              A director, officer, employee or stockholder, as such, of the
Company or any Guarantor shall not have any liability for any obligations of the
Company or a Guarantor under the Senior Notes, the Guarantees or this Indenture
or for any claim based on, in respect of or by reason of such obligations or
their creation. By accepting a Senior Note, each Holder shall waive and release
all such liability. The waiver and release shall be part of the consideration
for the issue of the Senior Notes.



                                       107




<PAGE>   115



SECTION 12.11. Submission to Jurisdiction; Appointment of Agent for Service of
Process; Waiver of Immunities.

              (a) The Company and each Guarantor hereby irrevocably, to the
fullest extent it may do so under applicable law, submits to the jurisdiction of
any New York State or federal court sitting in the Borough of Manhattan, The
City of New York and to the courts of its own corporate domicile with respect to
all actions brought against it as a defendant in respect of any suit, action or
proceeding or arbitral award arising out or relating to this Indenture, the
Senior Notes or any transaction contemplated hereby or thereby (a "Proceeding"),
and irrevocably accepts for itself and in respect of its property, generally and
unconditionally, the jurisdiction of the aforesaid courts, to the fullest extent
it may do so under applicable law. The Company and each Guarantor irrevocably
waives, to the fullest extent it may do so under applicable law, trial by jury
and any objection which it may now or hereafter have to the laying of the venue
of any such Proceeding brought in any such court and any claim that any such
Proceeding brought in any such court has been brought in an inconvenient forum.
The Company and each Guarantor acknowledges that it has, by separate written
instrument, irrevocably appointed CT Corporation System (the "Process Agent"),
with an office at 1633 Broadway, New York, New York 10019, as its authorized
agent to receive on behalf of the Company and each Guarantor and its property
service of copies of the summons and complaint and any other process which may
be served in any Proceeding, and that the Process Agent has accepted such
appointment. If for any reason such Process Agent shall cease to be such agent
for service of process, the Company and each Guarantor shall forthwith appoint a
new agent of recognized standing for service of process in the State of New
York, United States and deliver to the Trustee a copy of the new agent's
acceptance of that appointment within 30 days. Nothing herein shall affect the
right of the Trustee, any Paying Agent or any Holder to serve process in any
other manner permitted by law or to commence legal proceedings or otherwise
proceed against the Company or the Guarantors in any other court of competent
jurisdiction.

              (b) Service may be made by delivering by hand a copy of such
process to the Company or the Guarantors, as the case may be, in care of the
Process Agent at the address specified above. The Company and the Guarantors
hereby irrevocably authorize and direct the Process Agent to accept such service
on their behalf. Failure of the Process Agent to give notice to the Company or
the Guarantors or failure of the Company or the Guarantors to receive notice of
such service of process shall not affect in any way the validity of such service
on the Process Agent or the Company or the Guarantors. As an alternative method
of service, the Company and the Guarantors also irrevocably consent to the
service of any and all process in any such proceeding by the delivery by hand of
copies of such process to the Company or the Guarantors, as the case may be, at
the applicable address specified in Section 12.5 hereof or at the address most
recently furnished in writing by the Company or the Guarantors to the Trustee.
The Company and the Guarantors covenant and agree that they shall take any and
all reasonable action, including the execution and filing of any and all
documents, that may be necessary to continue the designation of the Process



                                       108




<PAGE>   116



Agent specified above in full force and effect during the term of the Senior
Notes, and to cause the Process Agent to continue to act as such.

              (c) The Company and the Guarantors irrevocably agree that, in any
Proceedings anywhere (whether for an injunction, specific performance or
otherwise), no immunity (to the extent that it may at any time exist, whether on
the grounds of sovereignty or otherwise) from such Proceedings, from attachment
(whether in aid of execution, before judgment or otherwise) of their assets or
from execution of judgment shall be claimed by them or on their behalf or with
respect to their assets, except to the extent required by applicable law, any
such immunity being irrevocably waived, to the fullest extent permitted by
applicable law. The Company and the Guarantors irrevocably agree that, where
permitted by applicable law, they and their assets are, and shall be, subject to
such Proceedings, attachment or execution in respect of their obligations under
this Indenture or the Senior Notes.

SECTION 12.12. Successors.

              All agreements of the Company in this Indenture and the Senior
Notes shall bind its successors. All agreements of the Trustee in this Indenture
shall bind its successors.

SECTION 12.13. Multiple Originals.

              The parties may sign any number of copies of this Indenture. Each
signed copy shall be an original, but all of them together represent the same
agreement. One signed copy is enough to prove this Indenture. This Indenture may
be executed in any number of counterparts, each of which shall be deemed an
original, but all such counterparts shall together constitute but one and the
same instrument.

SECTION 12.14. Table of Contents; Headings.

              The table of contents, cross-reference sheet and headings of the
Articles and Sections of this Indenture have been inserted for convenience of
reference only, are not intended to be considered a part hereof and shall not
modify or restrict any of the terms or provisions hereof.





                                       109




<PAGE>   117






                  IN WITNESS WHEREOF, the parties have caused this Indenture to
be duly executed as of the date first above written.



                           COMPANY:

                           GREY WOLF, INC.



                           By:/s/  DAVID W. WEHLMANN
                              --------------------------------------------------
                           Name:  David W. Wehlmann
                           Title: Sr. Vice President and Chief Financial Officer



                           GUARANTORS:

                           GREY WOLF DRILLING COMPANY



                           By:/s/ DAVID W. WEHLMANN
                              --------------------------------------------------
                           Name:  David W. Wehlmann
                           Title: Sr. Vice President and Chief Financial Officer



                           GREY WOLF INTERNATIONAL, INC.



                           By:/s/ DAVID W. WEHLMANN
                              --------------------------------------------------
                           Name: David W. Wehlmann
                           Title: Sr. Vice President and Chief Financial Officer



                           DI ENERGY, INC.



                           By: /s/ DAVID W. WEHLMANN
                              --------------------------------------------------
                           Name: David W. Wehlmann
                           Title: Sr. Vice President and Chief Financial Officer





<PAGE>   118








                           MURCO DRILLING CORPORATION



                           By: /s/DAVID W. WEHLMANN
                              --------------------------------------------------
                           Name: David W. Wehlmann
                           Title: Secretary



                           TRUSTEE:

                           CHASE BANK OF TEXAS,
                           NATIONAL ASSOCIATION



                           By:/s/ MAURI J. COWEN
                              --------------------------------------------------
                           Name: Mauri J. Cowen
                           Title: Vice President and Trust Officer










<PAGE>   119






                                                                       EXHIBIT A



                              (Face of Senior Note)

[THIS SENIOR NOTE IS A GLOBAL NOTE WITHIN THE MEANING OF THE INDENTURE
REFERRED TO ON THE REVERSE THEREOF.

UNLESS THIS SENIOR NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), NEW YORK, NEW YORK, TO
GREY WOLF, INC. (THE "COMPANY") OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY NOTE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO.
OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND
ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC) ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED
OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN
PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE
AND TRANSFERS OF PORTIONS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS MADE
IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN SECTION 2.6 OF THE INDENTURE
REFERRED TO ON THE REVERSE HEREOF.

THIS GLOBAL NOTE IS EXCHANGEABLE FOR A SENIOR NOTE IN DEFINITIVE, FULLY
REGISTERED FORM, WITHOUT INTEREST COUPONS, IF (A) DTC NOTIFIES THE COMPANY THAT
IT IS UNWILLING OR UNABLE TO CONTINUE AS DEPOSITORY FOR THIS GLOBAL NOTE OR IF
AT ANY TIME DTC CEASES TO BE A "CLEARING AGENCY" REGISTERED UNDER THE SECURITIES
EXCHANGE ACT OF 1934, AS AMENDED, AND A SUCCESSOR DEPOSITORY IS NOT APPOINTED BY
THE COMPANY WITHIN 90 DAYS OF SUCH NOTICE, (B) THE COMPANY EXECUTES AND DELIVERS
TO THE TRUSTEE A NOTICE THAT THIS GLOBAL NOTE SHALL BE SO TRANSFERABLE,
REGISTRABLE, AND EXCHANGEABLE, AND SUCH TRANSFER SHALL BE SO REGISTRABLE, OR (C)
AN EVENT OF DEFAULT (AS HEREINAFTER DEFINED) HAS OCCURRED AND IS CONTINUING WITH
RESPECT TO THE SENIOR NOTE.1]


[THIS SENIOR NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER THE
U.S. SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND,
ACCORDINGLY, MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE
TRANSFERRED WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN THE SECOND SENTENCE

                                       A-1



<PAGE>   120






HEREOF. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST HEREIN, THE HOLDER
(1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN
RULE 144A UNDER THE SECURITIES ACT) (A "QIB"), OR (B) IT IS ACQUIRING THIS
SENIOR NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE WITH REGULATION S UNDER THE
SECURITIES ACT, (2) AGREES THAT IT WILL NOT RESELL OR OTHERWISE TRANSFER THIS
NOTE EXCEPT (A) TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) TO A PERSON WHOM
THE SELLER REASONABLY BELIEVES IS A QIB PURCHASING FOR ITS OWN ACCOUNT OR FOR
THE ACCOUNT OF A QIB IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (C)
IN AN OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR 904 OF THE
SECURITIES ACT, (D) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER
THE SECURITIES ACT, (E) IN ACCORDANCE WITH ANOTHER EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND BASED UPON AN OPINION OF
COUNSEL ACCEPTABLE TO THE COMPANY) OR (F) PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT AND, IN EACH CASE, IN ACCORDANCE WITH THE APPLICABLE SECURITIES LAWS
OF ANY STATE OF THE UNITED STATES OR ANY OTHER APPLICABLE JURISDICTION AND (3)
AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS SENIOR NOTE OR AN
INTEREST HEREIN IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS
LEGEND. AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION" AND "UNITED STATES"
HAVE THE MEANINGS GIVEN TO THEM BY RULE 902 OF REGULATION S UNDER THE SECURITIES
ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO REFUSE TO
REGISTER ANY TRANSFER OF THIS SENIOR NOTE IN VIOLATION OF THE FOREGOING.](1)




- -----------
(1) This paragraph should be removed upon the exchange of Initial Senior Notes
for Exchange Notes in the Exchange Offer or upon the registration of Initial 
Senior Notes pursuant to the terms of the Registration Rights Agreement.


                                       A-2



<PAGE>   121







                     8-7/8% Senior Notes due 2007, Series B

                                 GREY WOLF, INC.

No.
CUSIP No. _____________
                                                                    $-----------

                  Grey Wolf, Inc. promises to pay to ___________ or registered
assigns, [the principal sum of Seventy-Five Million United States Dollars, or
such greater or lesser amount as may from time to time be endorsed on Schedule A
hereto](2) on July 1, 2007.

                  Interest Payment Dates: January 1 and July 1
                  Record Dates: December 15 and June 15

                  Reference is hereby made to the further provisions of this
Senior Note set forth on the reverse hereof, which further provisions shall for
all purposes have the same effect as if set forth at this place.

                  Unless the certificate of authorization hereon has been duly 
executed by the Trustee referred to on the reverse hereof by manual signature,
this Senior Note shall not be entitled to any benefit of this Indenture or be
valid or obligatory for any purpose. 


- -------- 
(2) This phrase should be included only if the Senior Note is issued in global 
    form.

                                       A-3



<PAGE>   122






IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.


                                    GREY WOLF, INC.



                                    By:
                                       -----------------------------------------
                                    Name:
                                         ---------------------------------------
                                    Title
                                         ---------------------------------------


Dated:   May 8, 1998


Certificate of Authentication:
This is one of the Senior Notes
referred to in the within-mentioned
Indenture:

CHASE BANK OF TEXAS, NATIONAL ASSOCIATION,
as Trustee


By:
   -------------------------------------------
              Authorized Signatory



                                       A-4



<PAGE>   123






                            (Reverse of Senior Note)

                      8-7/8% Senior Note due 2007, Series B

                  Capitalized terms used herein shall have the meanings assigned
to them in this Indenture referred to below unless otherwise indicated.

                  1. Interest. Grey Wolf, Inc., a Texas corporation (such
corporation, and its successors and assigns under the Indenture hereinafter
referred to, being called the "Company"), promises to pay interest on the
principal amount of this Senior Note at 8-7/8% per annum until Maturity and
shall pay Special Interest, if any, payable pursuant to the Registration Rights
Agreement referred to below. The Company will pay interest, if any, and Special
Interest, if any, semi-annually in arrears on January 1 and July 1 of each year
(each, an "Interest Payment Date"), or if any such day is not a Business Day, on
the next succeeding Business Day. Interest on the Senior Notes will accrue from
the most recent date to which interest has been paid or, if no interest has been
paid, from the Issue Date; provided that if there is no existing Default in the
payment of interest, and if this Senior Note is authenticated between a Record
Date referred to on the face hereof and the next succeeding Interest Payment
Date, interest shall accrue from such next succeeding Interest Payment Date;
provided, further, that the first Interest Payment Date shall be July 1, 1998.
The Company shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue installments of interest
("Defaulted Interest"), and Special Interest, if any, (without regard to any
applicable grace periods), from time to time on demand at the same rate to the
extent lawful. Interest will be computed on the basis of a 360-day year of
twelve 30-day months.

                  2. Method of Payment. The Company will pay interest on the
Senior Notes (except Defaulted Interest) and Special Interest, if any, to the
Persons who are registered Holders of Senior Notes at the close of business on
the December 15 and June 15 immediately preceding the Interest Payment Date
(each, a "Record Date"), even if such Senior Notes are canceled after such
Record Date and on or before such Interest Payment Date, except as provided in
Section 2.12 of the Indenture with respect to Defaulted Interest. The Senior
Notes will be payable as to principal, premium, interest and Special Interest at
the office or agency of the Company maintained for such purpose within the City
and State of New York, or, at the option of the Company, payment of interest and
Special Interest may be made by check mailed to the Holders at their addresses
set forth in the register of Holders, provided that payment by wire transfer of
immediately available funds will be required with respect to principal of and
interest, premium, if any, and Special Interest, if any, on, all Global Notes
and all other Senior Notes the Holders of which shall have provided wire
transfer instructions to the Company and the Paying Agent prior to the
applicable Record Date for such payment. Such payment shall be in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of public and private debts.

                  3. Paying Agent and Registrar. Initially, the Trustee under
the Indenture will act as Paying Agent and Registrar. The Company may change any
Paying Agent or Registrar without notice to any Holder. In certain situations,
the Company or any of its Subsidiaries may act in any such capacity.

                                       A-5



<PAGE>   124






                  4. Indenture. The Company issued the Senior Notes under an
Indenture dated as of May 8, 1998 (as such may be amended or supplemented,
"Indenture") between the Company, the Persons acting as guarantors and named
therein (the "Guarantors") and Chase Bank of Texas, National Association, as
trustee (the "Trustee," which term includes any successor trustee under the
Indenture). The terms of the Senior Notes include those stated in the Indenture
and those made part of the Indenture by reference to the U.S. Trust Indenture
Act of 1939, as amended (15 U.S. Code ss.ss. 77aaa-77bbbb) as in effect on the
date of the Indenture. The Senior Notes are subject to all such terms, and
Holders are referred to the Indenture and such Act for a statement of such
terms. The Senior Notes are unsecured obligations of the Company limited to
$75,000,000 in aggregate principal amount (subject to Section 2.2 of the
Indenture). This Senior Note is one of the Senior Notes referred to in the
Indenture.

                  5. Optional Redemption. (a) Except as set forth in clause 5(b)
of this Senior Note, the Senior Notes shall not be redeemable at the Company's
option prior to July 1, 2002. On or after such date, the Senior Notes shall be
redeemable at the option of the Company, in whole at any time or in part from
time to time, at the following prices (expressed in percentages of principal
amount thereof) if redeemed during the twelve-month period beginning after July
1 of each of the years indicated below, in each case together with interest (and
Special Interest, if any) accrued to the Redemption Date (subject to the right
of Holders of record on the relevant Record Date to receive interest (and
Special Interest, if any) due on the relevant Interest Payment Date):

<TABLE>
<CAPTION>


YEAR                                                                    PERCENTAGE
<S>                                                                     <C>
2002.............................................................       104.4375 %
2003.............................................................       102.9580 %
2004.............................................................       101.4792 %
2005 and thereafter..............................................       100.0000 %
</TABLE>


              (b) Notwithstanding the provisions of clause (a) of this clause 5,
at any time on or before June 27, 2000, the Company may at its option redeem up
to a maximum of 30% of the aggregate principal amount of the Senior Notes with
the net cash proceeds of one or more Qualified Equity Offerings at a Redemption
Price equal to 108.875% of the principal amount thereof, plus accrued and unpaid
interest (and Special Interest, if any), thereon to the Redemption Date;
provided that at least $50,000,000 of the aggregate principal amount of the
Senior Notes originally issued shall remain outstanding immediately after the
occurrence of such redemption; and provided, further, that such redemption shall
occur within 90 days of the date of the closing of such Qualified Equity
Offering.

              (c) Notices of redemption will be mailed by first class mail at
least 30 days but not more than 60 days before the Redemption Date to each
Holder whose Senior Notes are to be redeemed at its registered address. Senior
Notes in denominations larger than $1,000 may be redeemed in part but only in
integral multiples of $1,000, unless all of the Senior Notes held by a Holder
are to be redeemed. Unless the Company defaults in making such redemption
payment, on

                                       A-6



<PAGE>   125






and after the Redemption Date interest (including Special Interest, if any)
ceases to accrue on Senior Notes or portions thereof called for redemption.

                  6. Mandatory Redemption. Except as contemplated by clause 7
below, the Company shall not be required to make any mandatory redemption,
purchase or sinking fund payments with respect to the Senior Notes prior to the
maturity date.

                  7. Repurchase at Option of Holder. (a) Upon the occurrence of
a Change of Control, each Holder will have the right to require the Company to
repurchase such Holder's Senior Notes in whole or in part (the "Change of
Control Offer") at a purchase price (the "Change of Control Purchase Price") in
cash equal to 101% of the aggregate principal amount thereof, plus accrued and
unpaid interest thereon, if any, and Special Interest, if any, to the Change of
Control Payment Date on the terms described in the Indenture.

                  Within 30 days following any Change of Control, the Company
shall send, or cause to be sent, by first class mail, postage prepaid, a notice
regarding the Change of Control Offer to each Holder of Senior Notes. The Holder
of this Senior Note may elect to have this Senior Note or a portion hereof in an
authorized denomination purchased by completing the form entitled "Option of
Holder to Require Purchase" appearing below and tendering this Senior Note
pursuant to the Change of Control Offer. Unless the Company defaults in the
payment of the Change of Control Payment with respect thereto, all Senior Notes
or portions thereof accepted for payment pursuant to the Change of Control Offer
will cease to accrue interest (and Special Interest, if any) from and after the
Change of Control Purchase Date.

                  (b) Subject to the limitations set forth in the next following
paragraph and the Indenture, if at any time the Company or any Subsidiary
engages in an Asset Sale as result of which the aggregate amount of Excess
Proceeds exceeds $15,000,000, the Company shall within 30 days thereafter, or at
any time after receipt of Excess Proceeds but prior to there being $15,000,000
of Excess Proceeds, the Company may, at its option, make a pro rata offer (an
"Asset Sale Offer") to all Holders of Senior Notes and holders of other Senior
Debt, if and to the extent the Company is required by the instruments governing
such other Senior Debt to make such an offer, to purchase other Senior Notes and
such Senior Debt in an aggregate amount equal to the Excess Proceeds, at a price
in cash (the "Asset Sale Offer Purchase Price") equal to 100% of the outstanding
principal of the Senior Notes plus accrued interest and Special Interest, if
any, to the date of purchase and, in the case of such other Senior Debt, 100% of
the principal amount thereof, plus accrued and unpaid interest, if any, thereon
to the date of purchase. Upon completion of such Asset Sale Offer, the amount of
Excess Proceeds shall be reset to zero and the Company may use any remaining
amount for general corporate purposes.

         Within 30 days of the date the amount of Excess Proceeds exceeds
$15,000,000, the Company shall send, or cause to be sent, by first class mail,
postage prepaid, a notice regarding the Asset Sale Offer to each Holder of
Senior Notes. The Holder of this Senior Note may elect to have this Senior Note
or a portion hereof in an authorized denomination purchased by completing the
form entitled "Option of Holder to Elect Purchase" appearing below and tendering
this Senior Note

                                       A-7



<PAGE>   126






pursuant to the Asset Sale Offer. Unless the Company defaults in the payment of
the Asset Sale Offer Purchase Price with respect thereto, all Senior Notes or
portions thereof selected for payment pursuant to the Asset Sale Offer will
cease to accrue interest from and after the Asset Sale Offer Purchase Date.

                  8. Denominations; Transfer and Exchange. The Senior Notes are
in registered form without coupons in denominations of $1,000 and integral
multiples of $1,000. The transfer of Senior Notes may be registered and Senior
Notes may be exchanged as provided in the Indenture. The Registrar and the
Trustee may require a Holder, among other things, to furnish appropriate
endorsements and transfer documents (including in certain cases, opinions of
counsel) and the Company may require a Holder to pay any taxes and fees required
by law or permitted by the Indenture. The Company need not exchange or register
the transfer of any Senior Note or portion of a Senior Note selected for
redemption, except for the unredeemed portion of any Senior Note being redeemed
in part. Also, it need not exchange or register the transfer of any Senior Notes
for a period of 15 days before a selection of Senior Notes to be redeemed or
during the period between a Record Date and the corresponding Interest Payment
Date.

                  9. Persons Deemed Owners. The registered Holder of a Senior
Note may be treated as its owner for all purposes.

                  10. Amendment, Supplement and Waiver. With the consent of the
holders of not less than a majority in aggregate principal amount at Stated
Maturity of the outstanding Senior Notes (including consents obtained in
connection with a tender offer or exchange offer for the Senior Notes), the
Company, the Guarantors and the Trustee may enter into one or more indentures
supplemental to the Indenture for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of the Indenture or
of modifying in any manner the rights of the holders; provided that no such
supplemental indenture will, without the consent of the Holder of each
outstanding Senior Note affected thereby, (a) change the Stated Maturity of the
principal of, or any installment of interest on, any Senior Note, or reduce the
principal amount thereof (or premium, if any), or the interest thereon that
would be due and payable upon Maturity thereof, or change the place of payment
where, or the coin or currency in which, any Senior Note or any premium or
interest thereon is payable, or impair the right to institute suit for the
enforcement of any such payment on or after the Stated Maturity thereof, (b)
reduce the percentage in principal amount at Stated Maturity of the outstanding
Senior Notes, the consent of whose Holders is required for any such supplemental
indenture or required for any waiver of compliance with certain provisions of
the Indenture, (c) modify the Obligations of the Company to make offers to
purchase Senior Notes upon a Change of Control or from the proceeds of Asset
Sales, (d) subordinate in right of payment, or otherwise subordinate, the Senior
Notes or the Guarantees to any other Indebtedness, (e) amend, supplement or
otherwise modify the provisions of the Indenture relating to Guarantees or (f)
modify any of the provisions of this clause (except to increase any percentage
set forth herein).

                  11. Defaults and Remedies. Under the Indenture, Events of
Default include in summary form (i) default in the payment of interest on the
Senior Notes when due, continued for 30 days; (ii) default in the payment of
principal of (or premium, if any, on) the Senior Notes when due;

                                       A-8



<PAGE>   127






(iii) failure to comply with certain of the covenants in the Indenture,
including the Change of Control covenant, the Asset Sale covenant and the
Restrictive Payments covenant; (iv) failure to perform any other covenant of the
Company or any Guarantor in the Indenture, continued for 30 days after written
notice as provided in the Indenture; (v) Indebtedness of the Company or any
Subsidiary is not paid when due within the applicable grace period, or is
accelerated and, in either case, the principal amount of such unpaid
Indebtedness exceeds $10,000,000; (vi) one or more final judgments or orders by
a court of competent jurisdiction are entered against the Company or any
Subsidiary in an uninsured or unindemnified aggregate amount in excess of
$5,000,000 and such judgments or orders are not discharged, waived, appealed,
stayed, satisfied or bonded for a period of 60 consecutive days; (vii) certain
events of bankruptcy, insolvency or reorganization; or (viii) a Guarantee ceases
to be in full force and effect (other than in accordance with the terms of the
Indenture and such Guarantee) or a Guarantor denies or disaffirms its
obligations under its Guarantee.

         Holders may not enforce the Indenture or the Senior Notes except as
provided in the Indenture. The Trustee may refuse to enforce the Indenture or
the Senior Notes unless it receives reasonable indemnity or security. Subject to
certain limitations, Holders of a majority in principal amount at Stated
Maturity of the Senior Notes may direct the Trustee in its exercise of any trust
or power. The Trustee may withhold from Holders notice of any continuing Default
(except a Default in payment of principal or interest) if it determines that
withholding notice is in the interest of the Holders. The Holders of a majority
in principal amount at Stated Maturity of the outstanding Senior Notes, by
written notice to the Company and the Trustee, may rescind any declaration of
acceleration and its consequences if the rescission would not conflict with any
judgment or decree, and if all Events of Default have been cured or waived
except nonpayment of principal and interest that has become due solely because
of the acceleration.

                  12. Defeasance Prior to Maturity or Redemption. The Company,
at its election, shall (a) be deemed to have paid and discharged its debt on the
Senior Notes and the Indenture and Guarantees shall cease to be of further
effect as to all outstanding Senior Notes (except as to (i) rights of
registration of transfer, substitution and exchange of Senior Notes, (ii) the
Company's right of optional redemption, (iii) rights of Holders to receive
payments of principal of, premium, if any, and interest on the Senior Notes (but
not the Change of Control Purchase Price or the Asset Sale Offer Purchase Price)
and any rights of the Holders with respect to such amounts, (iv) the rights,
obligations and immunities of the Trustee under the Indenture, and (v) certain
other specified provisions in the Indenture) or (b) cease to be under any
obligation to comply with certain restrictive covenants that are described in
the Indenture, after the irrevocable deposit by the Company with the Trustee, in
trust for the benefit of the Holders, at any time prior to the Stated Maturity
of the Senior Notes, of (A) money in an amount, (B) U.S. Government Obligations
which through the payment of interest and principal will provide, not later than
one Business Day before the due date of payment in respect of such Senior Notes,
money in an amount, or (C) a combination thereof sufficient to pay and discharge
the principal of, premium, if any on, and interest (including Special Interest,
if any) on, such Senior Notes then outstanding on the dates on which any such
payments are due in accordance with the terms of the Indenture and of such
Senior Notes.


                                       A-9



<PAGE>   128






                  13. Trustee Dealings with the Company. Subject to certain
limitations imposed by the Trust Indenture Act, the Trustee, in its individual
or any other capacity, may make loans to, accept deposits from, and perform
services for the Company or its Affiliates, and may otherwise deal with the
Company or its Affiliates, as if it were not the Trustee.

                  14. No Recourse Against Others. A director, officer, employee,
incorporator or stockholder, of the Company or a Guarantor, as such, shall not
have any liability for any obligations of the Company or the Guarantors under
the Senior Notes, the Indenture, the Guarantees or for any claim based on, in
respect of, or by reason of, such Obligations or their creation. Each Holder by
accepting a Senior Note waives and releases all such liability. The waiver and
release are part of the consideration for the issuance of the Senior Notes.

                  15. GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SENIOR NOTE, WITHOUT REGARD TO THE
CONFLICTS OF LAWS PRINCIPLES THEREOF.

                  16. Authentication. This Senior Note shall not be valid until
authenticated by the manual signature of the Trustee or an authenticating agent.

                  17. Abbreviations. Customary abbreviations may be used in the
name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT
(= tenants by the entireties), JT TEN (= joint tenants with right of
survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (=
Uniform Gifts to Minors Act).

                  18. Additional Rights of Holders of Transfer Restricted Senior
Notes. In addition to the rights provided to Holders of Senior Notes under the
Indenture, Holders of Transferred Restricted Senior Notes (as defined in the
Registration Rights Agreement) shall have all the rights set forth in the
Registration Rights Agreement dated as of the date of the Indenture, between the
Company and the parties named on the signature pages thereof (the "Registration
Rights Agreement").

                  19. CUSIP Numbers. Pursuant to a recommendation promulgated by
the Committee on Uniform Senior Note Identification Procedures, the Company has
caused CUSIP numbers to be printed on the Senior Notes and the Trustee may use
CUSIP numbers in notices of redemption as a convenience to Holders. No
representation is made as to the accuracy of such numbers either as printed on
the Senior Notes or as contained in any notice of redemption and reliance may be
placed only on the other identification numbers placed thereon.

                  20. Indenture Governs. In the event of a conflict between the
terms of this Note and the terms of the Indenture, the terms of the Indenture
shall govern.




                                      A-10



<PAGE>   129







                  The Company will furnish to any Holder upon written request
and without charge a copy of the Indenture and/or the Registration Rights
Agreement. Requests may be made to:

                  Grey Wolf, Inc.
                  10370 Richmond Avenue
                  Suite 600
                  Houston, Texas  77042
                  Telephone No.: (713) 435-6100

                  Attention: Chief Financial Officer
                  Telephone No.: (713) 435-6100
                  Telecopier No.: (713) 435-6171


                                      A-11



<PAGE>   130






                                    GUARANTEE

         Subject to the limitations set forth in the Indenture, the Guarantors
(as defined in the Indenture referred to in this Senior Note and each
hereinafter referred to as a "Guarantor," which term includes any successor or
additional Guarantor under the Indenture) have jointly and severally,
irrevocably and unconditionally guaranteed (a) the due and punctual payment of
the principal (and premium, if any) of and interest (and Special Interest, if
any), on the Senior Notes, whether at Maturity, by acceleration, call for
redemption, upon a Change of Control Offer, Asset Sale Offer, purchase or
otherwise, (b) the due and punctual payment of interest on the overdue principal
of and interest, (and Special Interest, if any), on the Senior Notes to the
extent lawful, (c) the due and punctual performance of all other Obligations of
the Company and the Guarantors to the Holders under the Indenture and the Senior
Notes and (d) in case of any extension of time of payment or renewal of any
Senior Notes or any of such other Obligations, the same will be promptly paid in
full when due or performed in accordance with the terms of the extension or
renewal, whether at Maturity, by acceleration, call for redemption, upon a
Change of Control Offer, Asset Sale Offer, purchase or otherwise.

         Payment on each Senior Note is guaranteed, jointly and severally, by
the Guarantors pursuant to Article 11 of the Indenture and reference is made to
such Indenture for the precise terms of the Guarantees.

         The Obligations of each Guarantor are limited to the maximum amount as
will, after giving effect to such maximum amount and all other contingent and
fixed liabilities of such Guarantor, and after giving effect to any collections
from or payments made by or on behalf of any other Guarantor in respect of the
Obligations of such other Guarantor under its Guarantee or pursuant to its
contribution Obligations under the Indenture, result in the Obligations of such
Guarantor under its Guarantee not constituting a fraudulent conveyance or
fraudulent transfer under any applicable federal or state law or not otherwise
being void, voidable or unenforceable under any applicable bankruptcy,
reorganization, receivership, liquidation or other similar legislation or legal
principles under any applicable federal law. Each Guarantor that makes a payment
or distribution under a Guarantee shall be entitled to a contribution from each
other Guarantor in a pro rata amount based on the Adjusted Net Assets of each
Guarantor.

         Guarantors may be released from their Guarantees upon the terms and
subject to the conditions provided in the Indenture.

                                      A-12



<PAGE>   131







         The Guarantee shall be binding upon each Guarantor and its successors
and assigns and shall inure to the benefit of the Trustee and the Holders and,
in the event of any transfer or assignment of rights by any Holder or the
Trustee, the rights and privileges herein conferred upon that party shall
automatically extend to and be vested in such transferee or assignee, all
subject to the terms and conditions in the Indenture.



                                         GREY WOLF DRILLING COMPANY


                                         By:
                                            ------------------------------------
                                         Name:
                                              ----------------------------------
                                         Title:
                                               ---------------------------------



                                         GREY WOLF INTERNATIONAL, INC.



                                         By:
                                            ------------------------------------
                                         Name:
                                              ----------------------------------
                                         Title:
                                               ---------------------------------


                                         DI ENERGY, INC.


                                         By:
                                            ------------------------------------
                                         Name:
                                              ----------------------------------
                                         Title:
                                               ---------------------------------

                                         MURCO DRILLING CORPORATION



                                         By:
                                            ------------------------------------
                                         Name:
                                              ----------------------------------
                                         Title:
                                               ---------------------------------


                                      A-13



<PAGE>   132






                                 ASSIGNMENT FORM


To assign this Senior Note, fill in the form below: (I) or (we) assign and
transfer this Senior Note to

- -------------------------------------------------------------------------------
             (Insert assignee's Social Senior Note or tax I.D. no.)

- -------------------------------------------------------------------------------


- -------------------------------------------------------------------------------

- ------------------------------------------------------------------------------


- ------------------------------------------------------------------------------
              (Print or type assignee's name, address and zip code)

and irrevocably appoint 
                        -------------------------------------------------------
to transfer this Senior Note on the books of the Company or the agent appointed
by the Company to maintain such books. The agent appointed hereby may substitute
another to act for him.

- -------------------------------------------------------------------------------


Date:  
     -------------------------
                                 Your signature: ______________________________
                                    (Sign exactly as your name appears on
                                         the face of this Senior Note)


Signature Guarantee:

                                      A-14



<PAGE>   133






                       Option of Holder to Elect Purchase


                  If you want to elect to have this Senior Note purchased by the
Company pursuant to Section 4.7 or 4.9 of the Indenture, check the box below:

                       Section 4.7                        Section 4.9

                  If you want to elect to have only part of the Senior Note
purchased by the Company pursuant to Section 4.7 or Section 4.9 of the
Indenture, state the amount you elect to have purchased (must be an integral
multiple of $1,000): $__________________

Date:                                        Your Signature:
- -----------------------------
                                             (Sign exactly as your name appears 
                                             on the Senior Note)

                                             Social Senior Note or
                                             Tax Identification No.:
                                                                    ------------


Signature Guarantee:


                                      A-15



<PAGE>   134






                                   SCHEDULE A

                 CHANGES IN PRINCIPAL AMOUNT OF SENIOR NOTE(3)

                  The following changes in the principal amount of this Global
Note have been recorded:


<TABLE>
<CAPTION>


                                                                        Principal Amount of this
                         Amount of decrease in   Amount of increase in        Global Note            Signature of
                          Principal Amount of     Principal Amount of   following such decrease   authorized officer
  Date of Transaction      this Global Note        this Global Note          (or increase)         of Trustee
- ---------------------- ------------------------------------------------ ----------------------- -------------

<S>                      <C>                      <C>                   <C>                      <C>






</TABLE>










- --------
(3) This should be included only if the Senior Note is issued in global form.

                                      A-16



<PAGE>   135





                                                                     EXHIBIT B-1

          FORM OF CERTIFICATE FOR EXCHANGE OR REGISTRATION OF TRANSFER
                FROM U.S. GLOBAL NOTE TO REGULATION S GLOBAL NOTE
                (Pursuant to Section 2.6(a)(1) of the Indenture)

Chase Bank of Texas, National Association
600 Travis
Houston, Texas  77002
Attention:  Corporate Trust Administration

                  Re: 8-7/8% Senior Notes due 2007, Series B of Grey Wolf, Inc.

                  Reference is hereby made to the Indenture, dated as of May 8,
1998 (the "Indenture"), between Grey Wolf, Inc. (the "Company"), the Persons
acting as guarantors and named therein (the "Guarantors") and Chase Bank of
Texas, National Association, as trustee (the "Trustee"). Capitalized terms used
but not defined herein shall have the meanings given them in the Indenture.

                  This letter relates to U.S.$___________ principal amount of
Senior Notes which are evidenced by one or more U.S. Global Notes and held with
the Depository in the name of _____________ (the "Transferor"). The Transferor
has requested a transfer of such beneficial interest in the Senior Notes to a
Person who will take delivery thereof in the form of an equal principal amount
of Senior Notes evidenced by one or more Regulation S Global Notes, which
amount, immediately after such transfer, is to be held with the Depository
through Euroclear or Cedel or both.

                  In connection with such request and in respect of such Senior
Notes, the Transferor hereby certifies that such transfer has been effected in
compliance with the transfer restrictions applicable to the Global Notes and
pursuant to and in accordance with Rule 903 or Rule 904 of Regulation S under
the United States Securities Act of 1933, as amended (the "Securities Act"), and
accordingly the Transferor hereby further certifies that:

                  (1)      The offer of the Senior Notes was not made to a
                           person in the United States and, if the 40-day
                           restricted period has not yet expired and the
                           Transferor is a dealer (as defined in Section 2(12)
                           of the Securities Act), or a person receiving a
                           selling concession, fee or other remuneration in
                           respect of the Senior Notes being sold (collectively,
                           "Dealers"), (i) neither the Transferor or any person
                           acting on its behalf knows that the transferee is a
                           U.S. person and (ii) if the Transferor or any person
                           acting on its behalf knows that the transferee is a
                           Dealer, the Transferor or person acting on its behalf
                           has sent a confirmation or other notice to the
                           transferee stating that the Senior Notes may be
                           offered or sold during the 40-day restricted period
                           only in accordance with the provisions of Regulation
                           S, pursuant to registration under the

                                      B-1-1




<PAGE>   136





                           Securities Act or pursuant to an available exemption 
                           from the registration requirements of the Securities
                           Act;

                  (2)      either:

                           (a)      at the time the buy order was originated,
                                    the transferee was outside the United States
                                    or the Transferor and any person acting on
                                    its behalf reasonably believed and believes
                                    that the transferee was outside the United
                                    States; or

                           (b)      the transaction was executed in, on or
                                    through the facilities of a designated
                                    offshore securities market and neither the
                                    Transferor nor any person acting on its
                                    behalf knows that the transaction was
                                    prearranged with a buyer in the United
                                    States;

                  (3)      no directed selling efforts have been made in
                           contravention of the requirements of Rule 904(b) of
                           Regulation S;

                  (4)      the transaction is not part of a plan or scheme to
                           evade the registration provisions of the Securities
                           Act; and

                  (5)      upon completion of the transaction, the beneficial
                           interest being transferred as described above is to
                           be held with the Depository through Euroclear or
                           Cedel or both.

                  Upon giving effect to this request to exchange a beneficial
interest in a U.S. Global Note for a beneficial interest in a Regulation S
Global Note. The resulting beneficial interest shall be subject to the
restrictions on transfer applicable to Regulation S Global Notes pursuant to the
Indenture and the Securities Act and, if such transfer occurs prior to the end
of the 40-day restricted period associated with the initial offering of Senior
Notes, the additional restrictions applicable to transfers of interest in the
Regulation S Global Note.

                  This certificate and the statements contained herein are made
for your benefit and the benefit of the Company and Donaldson, Lufkin & Jenrette
Securities Corporation, Lehman Brothers, Inc. and Prudential Securities
Incorporated (collectively, the Initial Purchasers"), the Initial Purchasers of
such Senior Notes being transferred. We acknowledge that you, the Company and
the Initial Purchasers will rely upon our confirmations, acknowledgments and
agreements set forth herein, and we agree to notify you promptly in writing if
any of our representations or warranties herein ceases to be accurate and
complete. Terms used in this certificate and not otherwise defined in the
Indenture have the meanings set forth in Regulation S under the Securities Act.


                                      B-1-2




<PAGE>   137





                                              [Insert Name of Transferor]

                                              By:
                                                 -------------------------------
                                              Name:
                                                   -----------------------------
                                              Title:
                                                    ----------------------------
Dated:
      -------------------------------
cc:      Grey Wolf, Inc.
         Initial Purchasers


                                      B-1-3




<PAGE>   138





                                                                     EXHIBIT B-2


          FORM OF CERTIFICATE FOR EXCHANGE OR REGISTRATION OF TRANSFER
                FROM REGULATION S GLOBAL NOTE TO U.S. GLOBAL NOTE
                (Pursuant to Section 2.6(a)(ii) of the Indenture)


Chase Bank of Texas, National Association
600 Travis
Houston, Texas 77002
Attention:  Corporate Trust Administration

                  Re: 8-7/8%  Senior Notes due 2007, Series B of Grey Wolf, Inc.

                  Reference is hereby made to the Indenture dated as of May 8,
1998 (the "Indenture"), between Grey Wolf, Inc. (the "Company"), the Persons
acting as guarantors and named therein (the "Guarantors") and Chase Bank of
Texas, National Association, as trustee (the "Trustee"). Capitalized terms used
but not defined herein shall have the meanings given them in the Indenture.

                  This letter relates to $____________ principal amount of
Senior Notes which are evidenced by one or more Regulation S Global Notes and
held with the Depository through Euroclear or Cedel in the name of
_________________ (the "Transferor"). The Transferor has requested a transfer of
such beneficial interest in the Senior Notes to a Person who will take delivery
thereof in the form of an equal principal amount of Senior Notes evidenced by
one or more U.S.
Global Notes, to be held with the Depository.

                  In connection with such request and in respect of such Senior
Notes, the Transferor hereby certifies that:

                                   [CHECK ONE]

[  ]     such transfer is being effected pursuant to and in accordance with Rule
         144A under the United States Securities Act of 1933, as amended (the
         "Securities Act") and, accordingly, the Transferor hereby further
         certifies that the Senior Notes are being transferred to a Person that
         the Transferor reasonably believes is purchasing the Senior Notes for
         its own account, or for one or more accounts with respect to which such
         Person exercises sole investment discretion, and such Person and each
         such account is a "qualified institutional buyer" within the meaning of
         Rule 144A in a transaction meeting the requirements of Rule 144A;

                                       or

such transfer is being effected pursuant to and in accordance with Rule 144
under the Securities Act;

                                      B-2-1




<PAGE>   139






                                       or

[  ]     such transfer is being effected in an offshore transaction pursuant to 
         and in accordance with Rule 904 under the Securities Act;

                                       or

[  ]     such transfer is being effected pursuant to an effective registration 
         statement under the Securities Act;

                                       or

[  ]     such transfer is being effected pursuant to an exemption from the
         registration requirements of the Securities Act other than those
         contemplated above, and the Transferor hereby further certifies that
         the Senior Notes are being transferred in compliance with the transfer
         restrictions applicable to the Global Notes and in accordance with the
         requirements of the exemption claimed, which certification is supported
         by an Opinion of Counsel, provided by the transferor or the transferee
         (a copy of which the Transferor has attached to this certification) in
         form reasonably acceptable to the Company and to the Registrar, to the
         effect that such transfer is in compliance with the Securities Act;

and such Senior Notes are being transferred in compliance with any applicable
blue sky or securities laws of any state of the United States or any other
applicable jurisdiction.

                  Upon giving effect to this request to exchange a beneficial
interest in Regulation S Global Notes for a beneficial interest in U.S. Global
Notes, the resulting beneficial interest shall be subject to the restrictions on
transfer applicable to U.S. Global Notes pursuant to the Indenture and the
Securities Act.


                                      B-2-2




<PAGE>   140





                  This certificate and the statements contained herein are made
for your benefit and the benefit of the Company and Donaldson, Lufkin & Jenrette
Securities Corporations, Lehman Brothers, Inc. and Prudential Securities
Incorporated (collectively, the "Initial Purchasers"), the Initial Purchasers of
such Senior Notes being transferred. We acknowledge that you, the Company and
the Initial Purchasers will rely upon our confirmations, acknowledgments and
agreements set forth herein, and we agree to notify you promptly in writing if
any of our representations or warranties herein ceases to be accurate and
complete. Terms used in this certificate and not otherwise defined in the
Indenture have the meanings set forth in Regulation S under the Securities Act.

                                      [Insert Name of Transferor]



                                      By:
                                         ---------------------------------------
                                      Name:
                                           -------------------------------------
                                      Title:
                                            ------------------------------------

Dated: 
      --------------------------

cc:      Grey Wolf, Inc.
         Initial Purchasers


                                      B-2-3




<PAGE>   141





                                                                     EXHIBIT B-3

          FORM OF CERTIFICATE FOR EXCHANGE OR REGISTRATION OF TRANSFER
                           OF DEFINITIVE SENIOR NOTES
                  (Pursuant to Section 2.6(b) of the Indenture)



Chase Bank of Texas, National Association
600 Travis
Houston, Texas  77002
Attention:  Corporate Trust Administration

                  Re: 8-7/8% Senior Notes due 2007, Series B of Grey Wolf, Inc.

                  Reference is hereby made to the Indenture dated as of May 8,
1998 (the "Indenture"), between Grey Wolf, Inc. (the "Company"), the Persons
acting as guarantors and named therein (the "Guarantors") and Chase Bank of
Texas, National Association, as trustee (the "Trustee"). Capitalized terms used
but not defined herein shall have the meanings given them in the Indenture.

                  This relates to $_________ principal amount of Senior Notes
which are evidenced by one or more Certificated Senior Notes in the name of
______________ (the "Transferor"). The Transferor has requested an exchange or
transfer of such Certificated Senior Note(s) in the form of an equal principal
amount of Senior Notes evidenced by one or more Certificated Senior Notes, to be
delivered to the Transferor or, in the case of a transfer of such Senior Notes,
to such Person as the Transferor instructs the Trustee.

                  In connection with such request and in respect of the Senior
Notes surrendered to the Trustee herewith for exchange (the "Surrendered Senior
Notes"), the Holder of such Surrendered Senior Notes hereby certifies that:

                                   [CHECK ONE]

[  ]     the Surrendered Senior Notes are being acquired for the Transferor's 
         own account, without transfer;

                                       or

[  ]     the Surrendered Senior Notes are being transferred to the Company;

                                       or

[  ]     the Surrendered Senior Notes are being transferred pursuant to and in 
         accordance with Rule

                                      B-3-1




<PAGE>   142





         144A under the United States Securities Act of 1933, as amended (the
         "Securities Act"), and, accordingly, the Transferor hereby further
         certifies that the Surrendered Senior Notes are being transferred to a
         Person that the Transferor reasonably believes is purchasing the
         Surrendered Senior Notes for its own account, or for one or more
         accounts with respect to which such Person exercises sole investment
         discretion, and such Person and each such account is a "qualified
         institutional buyer" within the meaning of Rule 144A, in each case in a
         transaction meeting the requirements of Rule 144A;

                                       or

[  ]     the Surrendered Senior Notes are being transferred in a transaction 
         permitted by Rule 144 under the Securities Act;

                                       or

[  ]     the Surrendered Senior Notes are being transferred in an offshore 
         transaction pursuant to and in accordance with Rule 904 under the 
         Securities Act;

                                       or


[  ]     the Surrendered Senior Notes are being transferred pursuant to an 
         effective registration statement under the Securities Act;

                                       or

[  ]     such transfer is being effected pursuant to an exemption from the
         registration requirements of the Securities Act other than those
         contemplated above, and the Transferor hereby further certifies that
         the Senior Notes are being transferred in compliance with the transfer
         restrictions applicable to the Global Notes and in accordance with the
         requirements of the exemption claimed, which certification is supported
         by an Opinion of Counsel, provided by the transferor or the transferee
         (a copy of which the Transferor has attached to this certification) in
         form reasonably acceptable to the Company and to the Registrar, to the
         effect that such transfer is in compliance with the Securities Act;

and the Surrendered Senior Notes are being transferred in compliance with any
applicable blue sky or securities laws of any state of the United States or any
other applicable jurisdiction.

                  This certificate and the statements contained herein are made
for your benefit and the benefit of the Company and Donaldson, Lufkin & Jenrette
Securities Corporation, Lehman Brothers, Inc. and Prudential Securities
Incorporated (collectively, the "Initial Purchasers"), the Initial Purchasers of
such Senior Notes being transferred. We acknowledge that you, the Company and
the Initial Purchasers will rely upon our confirmations, acknowledgments and
agreements set forth

                                      B-3-2




<PAGE>   143





herein, and we agree to notify you promptly in writing if any of our
representations or warranties herein ceases to be accurate and complete. Terms
used in this certificate and not otherwise defined in the Indenture have the
meanings set forth in Regulation S under the Securities Act.

                                         [Insert Name of Transferor]



                                         By:
                                            ------------------------------------
                                         Name:
                                              ----------------------------------
                                         Title:
                                               ---------------------------------
Dated: 
      -------------------------------
cc:      Grey Wolf, Inc.
         Initial Purchasers


                                      B-3-3




<PAGE>   144





                                                                     EXHIBIT B-4

          FORM OF CERTIFICATE FOR EXCHANGE OR REGISTRATION OF TRANSFER
                      FROM U.S. GLOBAL NOTE OR REGULATION S
                              PERMANENT GLOBAL NOTE
                            TO DEFINITIVE SENIOR NOTE
                  (Pursuant to Section 2.6(c) of the Indenture)



Chase Bank of Texas, National Association
600 Travis
Houston, Texas  77002
Attention:  Corporate Trust Administration

                  Re: 8-7/8%  Senior Notes due 2007, Series B of Grey Wolf, Inc.

                  Reference is hereby made to the Indenture dated as of May 8,
1998 (the "Indenture"), between Grey Wolf, Inc. (the "Company"), the Persons
acting as guarantors and named therein (the "Guarantors") and Chase Bank of
Texas, National Association, as trustee (the "Trustee"). Capitalized terms used
but not defined herein shall have the meanings given them in the Indenture.

                  This letter relates to $_____________ principal amount of
Senior Notes which are evidenced by a beneficial interest in one or more U.S.
Global Notes or Regulation S Global Notes in the name of __________________ (the
"Transferor"). The Transferor has requested an exchange or transfer of such
beneficial interest in the form of an equal principal amount of Senior Notes
evidenced by one or more Certificated Senior Notes, to be delivered to the
Transferor or, in the case of a transfer of such Senior Notes, to such Person as
the Transferor instructs the Trustee.

                  In connection with such request and in respect of the Senior
Notes surrendered to the Trustee herewith for exchange (the "Surrendered Senior
Notes"), the Holder of such surrendered Senior Notes hereby certifies that:

                                   [CHECK ONE]

[  ]     the Surrendered Senior Notes are being transferred to the beneficial 
         owner of such Senior Notes;

                                       or

[   ]     the Surrendered Senior Notes are being transferred pursuant to and in 
          accordance

                                      B-4-1



<PAGE>   145





         with Rule 144A under the United States Securities Act of 1933, as
         amended (the "Securities Act"), and, accordingly, the Transferor hereby
         further certifies that the Surrendered Senior Notes are being
         transferred to a Person that the Transferor reasonably believes is
         purchasing the Surrendered Senior Notes for its own account, or for one
         or more accounts with respect to which such Person exercises sole
         investment discretion, and such Person and each such account is a
         "qualified institutional buyer" within the meaning of Rule 144A, in
         each case in a transaction meeting the requirements of Rule 144A;

                                       or

[  ]     the Surrendered Senior Notes are being transferred in a transaction 
         permitted by Rule 144 under the Securities Act;

                                       or

[  ]     such transfer is being effected in an offshore transaction pursuant to 
         and in accordance with Rule 904 under the Securities Act;

                                       or

[  ]     the Surrendered Senior Notes are being transferred pursuant to an 
         effective registration statement under the Securities Act;

                                       or

[  ]     the Surrendered Senior Notes are being transferred pursuant to an
         exemption from the registration requirements of the Securities Act
         other than those contemplated above, and the Transferor hereby further
         certifies that the Senior Notes are being transferred in compliance
         with the transfer restrictions applicable to the Global Notes and in
         accordance with the requirements of the exemption claimed, which
         certification is supported by an Opinion of Counsel, provided by the
         transferor or the transferee (a copy of which the Transferor has
         attached to this certification) in form reasonably acceptable to the
         Company and to the Registrar, to the effect that such transfer is in
         compliance with the Securities Act;

and the Surrendered Senior Notes are being transferred in compliance with any
applicable blue sky securities laws of any state of the United States.

                  This certificate and the statements contained herein are made
for your benefit and the benefit of the Company and Donaldson, Lufkin & Jenrette
Securities Corporation, Lehman Brothers, Inc. and Prudential Securities
Incorporated (collectively, the "Initial Purchasers"), the Initial Purchasers of
such Senior Notes being transferred. We acknowledge

                                      B-4-2



<PAGE>   146





that you, the Company and the Initial Purchasers will rely upon our
confirmations, acknowledgments and agreements set forth herein, and we agree to
notify you promptly in writing if any of our representations or warranties
herein ceases to be accurate and complete. Terms used in this certificate and
not otherwise defined in the Indenture have the meanings set forth in Regulation
S under the Securities Act.

                                            [Insert Name of Transferor]




                                            By:
                                               ---------------------------------
                                            Name:
                                                 -------------------------------
                                            Title:
                                                  ------------------------------

Dated: 
      ----------------------------
cc:      Grey Wolf, Inc.
         Initial Purchasers

                                      B-4-3



<PAGE>   147





                                                                       EXHIBIT C

                         FORM OF SUPPLEMENTAL INDENTURE



         SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of
_______________, among [GUARANTOR] (the "New Guarantor"), a subsidiary of Grey
Wolf, Inc. (or its successor), a Texas corporation (the "Company"), GREY WOLF,
INC., the Guarantors (the "Existing Guarantors") under the Indenture referred to
below, and Chase Bank of Texas, National Association, a national banking
association, as trustee under the Indenture referred to below (the "Trustee").

                              W I T N E S S E T H :

         WHEREAS the Company has heretofore executed and delivered to the
Trustee an Indenture (as such may be amended from time to time, the
"Indenture"), dated as of _______________, providing for the issuance of an
aggregate principal amount of $75,000,000 of 8-7/8% Senior Notes due 2007 (the
"Senior Notes");

         WHEREAS Section 11.8 of the Indenture provides that the Company is
required to cause the New Guarantor to execute and deliver to the Trustee a
supplemental indenture pursuant to which the New Guarantor shall jointly and
severally and unconditionally and irrevocably guarantee all of the Company's
Obligations under the Senior Notes and the Indenture pursuant to a Guarantee
contained in the Indenture on the terms and conditions set forth herein; and

         WHEREAS pursuant to Section 10.1 of the Indenture, the Trustee, the
Company and Existing Guarantors are authorized to execute and deliver this
Supplemental Indenture;

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the New
Guarantor, the Company, the Existing Guarantors and the Trustee mutually
covenant and agree for the equal and ratable benefit of the holders of the
Senior Notes as follows:

         1.  Definitions.  (a) Capitalized terms used herein without definition 
shall have the meanings assigned to them in the Indenture.

         (b) For all purposes of this Supplemental Indenture, except as
otherwise herein expressly provided or unless the context otherwise requires:
(i) the terms and expressions used herein shall have the same meanings as
corresponding terms and expressions used in the Indenture; and (ii) the words
"herein," "hereof" and "hereby" and other words of similar import used in this
Supplemental Indenture refer to this Supplemental Indenture as a whole and not
to any particular section hereof.

         2.  Agreement to Guarantee.  The New Guarantor hereby agrees, jointly 
and severally and unconditionally and irrevocably, with all other Guarantors, to
guarantee the Company's



                                       C-1

<PAGE>   148





Obligations under the Senior Notes and the Indenture on the terms and subject to
the conditions set forth in Article 11 of the Indenture and to be bound by all
other applicable provisions of the Indenture. From and after the date hereof,
the New Guarantor shall be a Guarantor for all purposes under the Indenture and
the Senior Notes.

         3. Ratification of Indenture; Supplemental Indentures Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed and all the terms, conditions and provisions thereof
shall remain in full force and effect. This Supplemental Indenture shall form a
part of the Indenture for all purposes, and every Holder of Senior Notes
heretofore or hereafter authenticated and delivered shall be bound hereby.

         4. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

         5. Trustee Makes No Representation. The Trustee makes no representation
as to the validity or sufficiency of this Supplemental Indenture.

         6. Counterparts. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

         7. Effect of Headings.  The Section headings herein are for convenience
only and shall not effect the construction thereof.

         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                                 [NEW GUARANTOR]



                                 By:
                                    --------------------------------------------
                                 Name:
                                      ------------------------------------------
                                 Title:
                                       -----------------------------------------


                                 GREY WOLF, INC.



                                 By:
                                    --------------------------------------------
                                 Name:
                                      ------------------------------------------
                                 Title:
                                       -----------------------------------------


                                       C-2

<PAGE>   149





                                 [ALL EXISTING GUARANTORS]



                                 By:
                                    --------------------------------------------
                                 Name:
                                      ------------------------------------------
                                 Title:
                                       -----------------------------------------




                                       C-3

<PAGE>   150





                                 CHASE BANK OF TEXAS,
                                 NATIONAL ASSOCIATION
                                 as Trustee

                                 By:
                                    --------------------------------------------
                                 Name:
                                      ------------------------------------------
                                 Title:
                                       -----------------------------------------










                                       C-4


<PAGE>   1
                                                                     EXHIBIT 4.4

                              (Face of Senior Note)

THIS SENIOR NOTE IS A GLOBAL NOTE WITHIN THE MEANING OF THE INDENTURE REFERRED
TO ON THE REVERSE THEREOF.

UNLESS THIS SENIOR NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), NEW YORK, NEW YORK, TO
GREY WOLF, INC. (THE "COMPANY") OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY NOTE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO.
OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND
ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC) ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED
OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN
PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE
AND TRANSFERS OF PORTIONS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS MADE
IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN SECTION 2.6 OF THE INDENTURE
REFERRED TO ON THE REVERSE HEREOF.

THIS GLOBAL NOTE IS EXCHANGEABLE FOR A SENIOR NOTE IN DEFINITIVE, FULLY
REGISTERED FORM, WITHOUT INTEREST COUPONS, IF (A) DTC NOTIFIES THE COMPANY THAT
IT IS UNWILLING OR UNABLE TO CONTINUE AS DEPOSITORY FOR THIS GLOBAL NOTE OR IF
AT ANY TIME DTC CEASES TO BE A "CLEARING AGENCY" REGISTERED UNDER THE SECURITIES
EXCHANGE ACT OF 1934, AS AMENDED, AND A SUCCESSOR DEPOSITORY IS NOT APPOINTED BY
THE COMPANY WITHIN 90 DAYS OF SUCH NOTICE, (B) THE COMPANY EXECUTES AND DELIVERS
TO THE TRUSTEE A NOTICE THAT THIS GLOBAL NOTE SHALL BE SO TRANSFERABLE,
REGISTRABLE, AND EXCHANGEABLE, AND SUCH TRANSFER SHALL BE SO REGISTRABLE, OR (C)
AN EVENT OF DEFAULT (AS HEREINAFTER DEFINED) HAS OCCURRED AND IS CONTINUING WITH
RESPECT TO THE SENIOR NOTE.


THIS SENIOR NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER THE
U.S. SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND,
ACCORDINGLY, MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE
TRANSFERRED WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN THE SECOND SENTENCE
HEREOF.  BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST HEREIN, THE


                                        1



<PAGE>   2



HOLDER (1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS
DEFINED IN RULE 144A UNDER THE SECURITIES ACT) (A "QIB"), OR (B) IT IS ACQUIRING
THIS SENIOR NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE WITH REGULATION S
UNDER THE SECURITIES ACT, (2) AGREES THAT IT WILL NOT RESELL OR OTHERWISE
TRANSFER THIS NOTE EXCEPT (A) TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) TO
A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QIB PURCHASING FOR ITS OWN
ACCOUNT OR FOR THE ACCOUNT OF A QIB IN A TRANSACTION MEETING THE REQUIREMENTS OF
RULE 144A, (C) IN AN OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903
OR 904 OF THE SECURITIES ACT, (D) IN A TRANSACTION MEETING THE REQUIREMENTS OF
RULE 144 UNDER THE SECURITIES ACT, (E) IN ACCORDANCE WITH ANOTHER EXEMPTION FROM
THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND BASED UPON AN OPINION
OF COUNSEL ACCEPTABLE TO THE COMPANY) OR (F) PURSUANT TO AN EFFECTIVE
REGISTRATION STATEMENT AND, IN EACH CASE, IN ACCORDANCE WITH THE APPLICABLE
SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR ANY OTHER APPLICABLE
JURISDICTION AND (3) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS
SENIOR NOTE OR AN INTEREST HEREIN IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE
EFFECT OF THIS LEGEND. AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION" AND
"UNITED STATES" HAVE THE MEANINGS GIVEN TO THEM BY RULE 902 OF REGULATION S
UNDER THE SECURITIES ACT. THE INDENTURE CONTAINS A PROVISION REQUIRING THE
TRUSTEE TO REFUSE TO REGISTER ANY TRANSFER OF THIS SENIOR NOTE IN VIOLATION OF
THE FOREGOING.




                                        2



<PAGE>   3




                     8 7/8% Senior Notes due 2007, Series B

                                 GREY WOLF, INC.

No. R-001
CUSIP No.  397888 AA 6
                                                                     $75,000,000

                  Grey Wolf, Inc. promises to pay to CEDE & CO. or registered
assigns, the principal sum of SEVENTY-FIVE MILLION UNITED STATES DOLLARS, or
such greater or lesser amount as may from time to time be endorsed on Schedule A
hereto, on July 1, 2007.

                  Interest Payment Dates: January 1 and July 1
                  Record Dates: December 15 and June 15

                  Reference is hereby made to the further provisions of this
Senior Note set forth on the reverse hereof, which further provisions shall for
all purposes have the same effect as if set forth at this place.

                  Unless the certificate of authorization hereon has been duly
executed by the Trustee referred to on the reverse hereof by manual signature,
this Senior Note shall not be entitled to any benefit of this Indenture or be
valid or obligatory for any purpose.


                                        3



<PAGE>   4



IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.


                                       GREY WOLF, INC.



                                       By:  /s/ DAVID W. WEHLMANN
                                          --------------------------------------
                                       Name:    David W. Wehlmann
                                            ------------------------------------
                                       Title:   Senior Vice President and
                                             -----------------------------------
                                                Chief Financial Officer 
                                             -----------------------------------
 


Dated:   May 8, 1998


Certificate of Authentication:
This is one of the Senior Notes
referred to in the within-mentioned
Indenture:

CHASE BANK OF TEXAS, NATIONAL ASSOCIATION,
as Trustee


By: /s/ MAURI J. COWEN
   --------------------------------------------
              Authorized Signatory




                                        4



<PAGE>   5



                            (Reverse of Senior Note)

                      8 7/8% Senior Note due 2007, Series B

                  Capitalized terms used herein shall have the meanings assigned
to them in this Indenture referred to below unless otherwise indicated.

                  1. Interest. Grey Wolf, Inc., a Texas corporation (such
corporation, and its successors and assigns under the Indenture hereinafter
referred to, being called the "Company"), promises to pay interest on the
principal amount of this Senior Note at 8 7/8% per annum until Maturity and
shall pay Special Interest, if any, payable pursuant to the Registration Rights
Agreement referred to below. The Company will pay interest, if any, and Special
Interest, if any, semi-annually in arrears on January 1 and July 1 of each year
(each, an "Interest Payment Date"), or if any such day is not a Business Day, on
the next succeeding Business Day. Interest on the Senior Notes will accrue from
the most recent date to which interest has been paid or, if no interest has been
paid, from the Issue Date; provided that if there is no existing Default in the
payment of interest, and if this Senior Note is authenticated between a Record
Date referred to on the face hereof and the next succeeding Interest Payment
Date, interest shall accrue from such next succeeding Interest Payment Date;
provided, further, that the first Interest Payment Date shall be July 1, 1998.
The Company shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue installments of interest
("Defaulted Interest"), and Special Interest, if any, (without regard to any
applicable grace periods), from time to time on demand at the same rate to the
extent lawful. Interest will be computed on the basis of a 360-day year of
twelve 30-day months.

                  2. Method of Payment. The Company will pay interest on the
Senior Notes (except Defaulted Interest) and Special Interest, if any, to the
Persons who are registered Holders of Senior Notes at the close of business on
the December 15 and June 15 immediately preceding the Interest Payment Date
(each, a "Record Date"), even if such Senior Notes are canceled after such
Record Date and on or before such Interest Payment Date, except as provided in
Section 2.12 of the Indenture with respect to Defaulted Interest. The Senior
Notes will be payable as to principal, premium, interest and Special Interest at
the office or agency of the Company maintained for such purpose within the City
and State of New York, or, at the option of the Company, payment of interest and
Special Interest may be made by check mailed to the Holders at their addresses
set forth in the register of Holders, provided that payment by wire transfer of
immediately available funds will be required with respect to principal of and
interest, premium, if any, and Special Interest, if any, on, all Global Notes
and all other Senior Notes the Holders of which shall have provided wire
transfer instructions to the Company and the Paying Agent prior to the
applicable Record Date for such payment. Such payment shall be in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of public and private debts.

                  3. Paying Agent and Registrar. Initially, the Trustee under
the Indenture will act as Paying Agent and Registrar. The Company may change any
Paying Agent or Registrar without notice to any Holder. In certain situations,
the Company or any of its Subsidiaries may act in any such capacity.


                                        5



<PAGE>   6



                  4. Indenture. The Company issued the Senior Notes under an
Indenture dated as of May 8, 1998 (as such may be amended or supplemented,
"Indenture") between the Company, the Persons acting as guarantors and named
therein (the "Guarantors") and Chase Bank of Texas, National Association, as
trustee (the "Trustee," which term includes any successor trustee under the
Indenture). The terms of the Senior Notes include those stated in the Indenture
and those made part of the Indenture by reference to the U.S. Trust Indenture
Act of 1939, as amended (15 U.S. Code ss.ss. 77aaa-77bbbb) as in effect on the
date of the Indenture. The Senior Notes are subject to all such terms, and
Holders are referred to the Indenture and such Act for a statement of such
terms. The Senior Notes are unsecured obligations of the Company limited to
$75,000,000 in aggregate principal amount (subject to Section 2.2 of the
Indenture). This Senior Note is one of the Senior Notes referred to in the
Indenture.

                  5. Optional Redemption. (a) Except as set forth in clause 5(b)
of this Senior Note, the Senior Notes shall not be redeemable at the Company's
option prior to July 1, 2002. On or after such date, the Senior Notes shall be
redeemable at the option of the Company, in whole at any time or in part from
time to time, at the following prices (expressed in percentages of principal
amount thereof) if redeemed during the twelve-month period beginning after July
1 of each of the years indicated below, in each case together with interest (and
Special Interest, if any) accrued to the Redemption Date (subject to the right
of Holders of record on the relevant Record Date to receive interest (and
Special Interest, if any) due on the relevant Interest Payment Date):

<TABLE>
<CAPTION>

YEAR                                                          PERCENTAGE
<S>                                                            <C>
2002 .......................................................   104.4375 %
2003 .......................................................   102.9580 %
2004 .......................................................   101.4792 %
2005 and thereafter ........................................   100.0000 %
</TABLE>


                  (b) Notwithstanding the provisions of clause (a) of this
clause 5, at any time on or before June 27, 2000, the Company may at its option
redeem up to a maximum of 30% of the aggregate principal amount of the Senior
Notes with the net cash proceeds of one or more Qualified Equity Offerings at a
Redemption Price equal to 108.875% of the principal amount thereof, plus accrued
and unpaid interest (and Special Interest, if any), thereon to the Redemption
Date; provided that at least $50,000,000 of the aggregate principal amount of
the Senior Notes originally issued shall remain outstanding immediately after
the occurrence of such redemption; and provided, further, that such redemption
shall occur within 90 days of the date of the closing of such Qualified Equity
Offering.

                  (c) Notices of redemption will be mailed by first class mail
at least 30 days but not more than 60 days before the Redemption Date to each
Holder whose Senior Notes are to be redeemed at its registered address. Senior
Notes in denominations larger than $1,000 may be redeemed in part but only in
integral multiples of $1,000, unless all of the Senior Notes held by a Holder
are to be redeemed. Unless the Company defaults in making such redemption
payment, on


                                        6



<PAGE>   7



and after the Redemption Date interest (including Special Interest, if any)
ceases to accrue on Senior Notes or portions thereof called for redemption.

                  6. Mandatory Redemption. Except as contemplated by clause 7
below, the Company shall not be required to make any mandatory redemption,
purchase or sinking fund payments with respect to the Senior Notes prior to the
maturity date.

                  7. Repurchase at Option of Holder. (a) Upon the occurrence of
a Change of Control, each Holder will have the right to require the Company to
repurchase such Holder's Senior Notes in whole or in part (the "Change of
Control Offer") at a purchase price (the "Change of Control Purchase Price") in
cash equal to 101% of the aggregate principal amount thereof, plus accrued and
unpaid interest thereon, if any, and Special Interest, if any, to the Change of
Control Payment Date on the terms described in the Indenture.

                  Within 30 days following any Change of Control, the Company
shall send, or cause to be sent, by first class mail, postage prepaid, a notice
regarding the Change of Control Offer to each Holder of Senior Notes. The Holder
of this Senior Note may elect to have this Senior Note or a portion hereof in an
authorized denomination purchased by completing the form entitled "Option of
Holder to Require Purchase" appearing below and tendering this Senior Note
pursuant to the Change of Control Offer. Unless the Company defaults in the
payment of the Change of Control Payment with respect thereto, all Senior Notes
or portions thereof accepted for payment pursuant to the Change of Control Offer
will cease to accrue interest (and Special Interest, if any) from and after the
Change of Control Purchase Date.

                  (b) Subject to the limitations set forth in the next following
paragraph and the Indenture, if at any time the Company or any Subsidiary
engages in an Asset Sale as result of which the aggregate amount of Excess
Proceeds exceeds $15,000,000, the Company shall within 30 days thereafter, or at
any time after receipt of Excess Proceeds but prior to there being $15,000,000
of Excess Proceeds, the Company may, at its option, make a pro rata offer (an
"Asset Sale Offer") to all Holders of Senior Notes and holders of other Senior
Debt, if and to the extent the Company is required by the instruments governing
such other Senior Debt to make such an offer, to purchase Senior Notes and such
other Senior Debt in an aggregate amount equal to the Excess Proceeds, at a
price in cash (the "Asset Sale Offer Purchase Price") equal to 100% of the
outstanding principal of the Senior Notes plus accrued interest and Special
Interest, if any, to the date of purchase and, in the case of such other Senior
Debt, 100% of the principal amount thereof, plus accrued and unpaid interest, if
any, thereon to the date of purchase. Upon completion of such Asset Sale Offer,
the amount of Excess Proceeds shall be reset to zero and the Company may use any
remaining amount for general corporate purposes.

         Within 30 days of the date the amount of Excess Proceeds exceeds
$15,000,000, the Company shall send, or cause to be sent, by first class mail,
postage prepaid, a notice regarding the Asset Sale Offer to each Holder of
Senior Notes. The Holder of this Senior Note may elect to have this Senior Note
or a portion hereof in an authorized denomination purchased by completing the
form entitled "Option of Holder to Elect Purchase" appearing below and tendering
this Senior Note


                                        7



<PAGE>   8



pursuant to the Asset Sale Offer. Unless the Company defaults in the payment of
the Asset Sale Offer Purchase Price with respect thereto, all Senior Notes or
portions thereof selected for payment pursuant to the Asset Sale Offer will
cease to accrue interest from and after the Asset Sale Offer Purchase Date.

                  8. Denominations; Transfer and Exchange. The Senior Notes are
in registered form without coupons in denominations of $1,000 and integral
multiples of $1,000. The transfer of Senior Notes may be registered and Senior
Notes may be exchanged as provided in the Indenture. The Registrar and the
Trustee may require a Holder, among other things, to furnish appropriate
endorsements and transfer documents (including in certain cases, opinions of
counsel) and the Company may require a Holder to pay any taxes and fees required
by law or permitted by the Indenture. The Company need not exchange or register
the transfer of any Senior Note or portion of a Senior Note selected for
redemption, except for the unredeemed portion of any Senior Note being redeemed
in part. Also, it need not exchange or register the transfer of any Senior Notes
for a period of 15 days before a selection of Senior Notes to be redeemed or
during the period between a Record Date and the corresponding Interest Payment
Date.

                  9. Persons Deemed Owners. The registered Holder of a Senior
Note may be treated as its owner for all purposes.

                  10. Amendment, Supplement and Waiver. With the consent of the
holders of not less than a majority in aggregate principal amount at Stated
Maturity of the outstanding Senior Notes (including consents obtained in
connection with a tender offer or exchange offer for the Senior Notes), the
Company, the Guarantors and the Trustee may enter into one or more indentures
supplemental to the Indenture for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of the Indenture or
of modifying in any manner the rights of the holders; provided that no such
supplemental indenture will, without the consent of the Holder of each
outstanding Senior Note affected thereby, (a) change the Stated Maturity of the
principal of, or any installment of interest on, any Senior Note, or reduce the
principal amount thereof (or premium, if any), or the interest thereon that
would be due and payable upon Maturity thereof, or change the place of payment
where, or the coin or currency in which, any Senior Note or any premium or
interest thereon is payable, or impair the right to institute suit for the
enforcement of any such payment on or after the Stated Maturity thereof, (b)
reduce the percentage in principal amount at Stated Maturity of the outstanding
Senior Notes, the consent of whose Holders is required for any such supplemental
indenture or required for any waiver of compliance with certain provisions of
the Indenture, (c) modify the Obligations of the Company to make offers to
purchase Senior Notes upon a Change of Control or from the proceeds of Asset
Sales, (d) subordinate in right of payment, or otherwise subordinate, the Senior
Notes or the Guarantees to any other Indebtedness, (e) amend, supplement or
otherwise modify the provisions of the Indenture relating to Guarantees or (f)
modify any of the provisions of this clause (except to increase any percentage
set forth herein).

                  11. Defaults and Remedies. Under the Indenture, Events of
Default include in summary form (i) default in the payment of interest on the
Senior Notes when due, continued for 30 days; (ii) default in the payment of
principal of (or premium, if any, on) the Senior Notes when due;


                                        8



<PAGE>   9



(iii) failure to comply with certain of the covenants in the Indenture,
including the Change of Control covenant, the Asset Sale covenant and the
Restrictive Payments covenant; (iv) failure to perform any other covenant of the
Company or any Guarantor in the Indenture, continued for 30 days after written
notice as provided in the Indenture; (v) Indebtedness of the Company or any
Subsidiary is not paid when due within the applicable grace period, or is
accelerated and, in either case, the principal amount of such unpaid
Indebtedness exceeds $10,000,000; (vi) one or more final judgments or orders by
a court of competent jurisdiction are entered against the Company or any
Subsidiary in an uninsured or unindemnified aggregate amount in excess of
$5,000,000 and such judgments or orders are not discharged, waived, appealed,
stayed, satisfied or bonded for a period of 60 consecutive days; (vii) certain
events of bankruptcy, insolvency or reorganization; or (viii) a Guarantee ceases
to be in full force and effect (other than in accordance with the terms of the
Indenture and such Guarantee) or a Guarantor denies or disaffirms its
obligations under its Guarantee.

         Holders may not enforce the Indenture or the Senior Notes except as
provided in the Indenture. The Trustee may refuse to enforce the Indenture or
the Senior Notes unless it receives reasonable indemnity or security. Subject to
certain limitations, Holders of a majority in principal amount at Stated
Maturity of the Senior Notes may direct the Trustee in its exercise of any trust
or power. The Trustee may withhold from Holders notice of any continuing Default
(except a Default in payment of principal or interest) if it determines that
withholding notice is in the interest of the Holders. The Holders of a majority
in principal amount at Stated Maturity of the outstanding Senior Notes, by
written notice to the Company and the Trustee, may rescind any declaration of
acceleration and its consequences if the rescission would not conflict with any
judgment or decree, and if all Events of Default have been cured or waived
except nonpayment of principal and interest that has become due solely because
of the acceleration.

                  12. Defeasance Prior to Maturity or Redemption. The Company,
at its election, shall (a) be deemed to have paid and discharged its debt on the
Senior Notes and the Indenture and Guarantees shall cease to be of further
effect as to all outstanding Senior Notes (except as to (i) rights of
registration of transfer, substitution and exchange of Senior Notes, (ii) the
Company's right of optional redemption, (iii) rights of Holders to receive
payments of principal of, premium, if any, and interest on the Senior Notes (but
not the Change of Control Purchase Price or the Asset Sale Offer Purchase Price)
and any rights of the Holders with respect to such amounts, (iv) the rights,
obligations and immunities of the Trustee under the Indenture, and (v) certain
other specified provisions in the Indenture) or (b) cease to be under any
obligation to comply with certain restrictive covenants that are described in
the Indenture, after the irrevocable deposit by the Company with the Trustee, in
trust for the benefit of the Holders, at any time prior to the Stated Maturity
of the Senior Notes, of (A) money in an amount, (B) U.S. Government Obligations
which through the payment of interest and principal will provide, not later than
one Business Day before the due date of payment in respect of such Senior Notes,
money in an amount, or (C) a combination thereof sufficient to pay and discharge
the principal of, premium, if any on, and interest (including Special Interest,
if any) on, such Senior Notes then outstanding on the dates on which any such
payments are due in accordance with the terms of the Indenture and of such
Senior Notes.



                                        9



<PAGE>   10



                  13. Trustee Dealings with the Company. Subject to certain
limitations imposed by the Trust Indenture Act, the Trustee, in its individual
or any other capacity, may make loans to, accept deposits from, and perform
services for the Company or its Affiliates, and may otherwise deal with the
Company or its Affiliates, as if it were not the Trustee.

                  14. No Recourse Against Others. A director, officer, employee,
incorporator or stockholder, of the Company or a Guarantor, as such, shall not
have any liability for any obligations of the Company or the Guarantors under
the Senior Notes, the Indenture, the Guarantees or for any claim based on, in
respect of, or by reason of, such Obligations or their creation. Each Holder by
accepting a Senior Note waives and releases all such liability. The waiver and
release are part of the consideration for the issuance of the Senior Notes.

                  15. GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SENIOR NOTE, WITHOUT REGARD TO THE
CONFLICTS OF LAWS PRINCIPLES THEREOF.

                  16. Authentication. This Senior Note shall not be valid until
authenticated by the manual signature of the Trustee or an authenticating agent.

                  17. Abbreviations. Customary abbreviations may be used in the
name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT
(= tenants by the entireties), JT TEN (= joint tenants with right of
survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (=
Uniform Gifts to Minors Act).

                  18. Additional Rights of Holders of Transfer Restricted Senior
Notes. In addition to the rights provided to Holders of Senior Notes under the
Indenture, Holders of Transferred Restricted Senior Notes (as defined in the
Registration Rights Agreement) shall have all the rights set forth in the
Registration Rights Agreement dated as of the date of the Indenture, between the
Company and the parties named on the signature pages thereof (the "Registration
Rights Agreement").

                  19. CUSIP Numbers. Pursuant to a recommendation promulgated by
the Committee on Uniform Senior Note Identification Procedures, the Company has
caused CUSIP numbers to be printed on the Senior Notes and the Trustee may use
CUSIP numbers in notices of redemption as a convenience to Holders. No
representation is made as to the accuracy of such numbers either as printed on
the Senior Notes or as contained in any notice of redemption and reliance may be
placed only on the other identification numbers placed thereon.



                                       10



<PAGE>   11




                  The Company will furnish to any Holder upon written request
and without charge a copy of the Indenture and/or the Registration Rights
Agreement. Requests may be made to:

                  Grey Wolf, Inc.
                  10370 Richmond Avenue
                  Suite 600
                  Houston, Texas  77042
                  Telephone No.: (713) 435-6100

                  Attention: Chief Financial Officer
                  Telephone No.: (713) 435-6100
                  Telecopier No.: (713) 435-6171




                                       11



<PAGE>   12



                                    GUARANTEE

         Subject to the limitations set forth in the Indenture, the Guarantors
(as defined in the Indenture referred to in this Senior Note and each
hereinafter referred to as a "Guarantor," which term includes any successor or
additional Guarantor under the Indenture) have jointly and severally,
irrevocably and unconditionally guaranteed (a) the due and punctual payment of
the principal (and premium, if any) of and interest, (and Special Interest, if
any), on the Senior Notes, whether at Maturity, by acceleration, call for
redemption, upon a Change of Control Offer, Asset Sale Offer, purchase or
otherwise, (b) the due and punctual payment of interest on the overdue principal
of and interest, (and Special Interest, if any), on the Senior Notes to the
extent lawful, (c) the due and punctual performance of all other Obligations of
the Company and the Guarantors to the Holders under the Indenture and the Senior
Notes and (d) in case of any extension of time of payment or renewal of any
Senior Notes or any of such other Obligations, the same will be promptly paid in
full when due or performed in accordance with the terms of the extension or
renewal, whether at Maturity, by acceleration, call for redemption, upon a
Change of Control Offer, Asset Sale Offer, purchase or otherwise.

         Payment on each Senior Note is guaranteed, jointly and severally, by
the Guarantors pursuant to Article 11 of the Indenture and reference is made to
such Indenture for the precise terms of the Guarantees.

         The Obligations of each Guarantor are limited to the maximum amount as
will, after giving effect to such maximum amount and all other contingent and
fixed liabilities of such Guarantor, and after giving effect to any collections
from or payments made by or on behalf of any other Guarantor in respect of the
Obligations of such other Guarantor under its Guarantee or pursuant to its
contribution Obligations under the Indenture, result in the Obligations of such
Guarantor under its Guarantee not constituting a fraudulent conveyance or
fraudulent transfer under any applicable federal or state law or not otherwise
being void, voidable or unenforceable under any applicable bankruptcy,
reorganization, receivership, liquidation or other similar legislation or legal
principles under any applicable federal law. Each Guarantor that makes a payment
or distribution under a Guarantee shall be entitled to a contribution from each
other Guarantor in a pro rata amount based on the Adjusted Net Assets of each
Guarantor.

         Guarantors may be released from their Guarantees upon the terms and
subject to the conditions provided in the Indenture.






<PAGE>   13




         The Guarantee shall be binding upon each Guarantor and its successors
and assigns and shall inure to the benefit of the Trustee and the Holders and,
in the event of any transfer or assignment of rights by any Holder or the
Trustee, the rights and privileges herein conferred upon that party shall
automatically extend to and be vested in such transferee or assignee, all
subject to the terms and conditions in the Indenture.



                          GREY WOLF DRILLING COMPANY


                          By:/s/ DAVID W. WEHLMANN
                             ---------------------------------------------------
                          Name:  David W. Wehlmann
                          Title:  Sr. Vice President and Chief Financial Officer



                          GREY WOLF INTERNATIONAL, INC.



                          By:/s/ DAVID W. WEHLMANN
                             ---------------------------------------------------
                          Name: David W. Wehlmann
                          Title:  Sr. Vice President and Chief Financial Officer



                          DI ENERGY, INC.


                          By: /s/ DAVID W. WEHLMANN
                             ---------------------------------------------------
                          Name: David W. Wehlmann
                          Title: Sr. Vice President and Chief Financial Officer


                          MURCO DRILLING CORPORATION



                          By: /s/ DAVID W. WEHLMANN
                             ---------------------------------------------------
                          Name: David W. Wehlmann
                          Title: Secretary








<PAGE>   14



                                 ASSIGNMENT FORM


To assign this Senior Note, fill in the form below: (I) or (we) assign and
transfer this Senior Note to


- -------------------------------------------------------------------------------
             (Insert assignee's Social Senior Note or tax I.D. no.)

- -------------------------------------------------------------------------------


- -------------------------------------------------------------------------------

- ------------------------------------------------------------------------------


- ------------------------------------------------------------------------------
              (Print or type assignee's name, address and zip code)

and irrevocably appoint 
                       -------------------------------------------------------
to transfer this Senior Note on the books of the Company or the agent appointed
by the Company to maintain such books. The agent appointed hereby may substitute
another to act for him.

- -------------------------------------------------------------------------------


Date:  
     --------------------------
                               Your signature: 
                                              ----------------------------------
                                              (Sign exactly as your name appears
                                               on the face of
this Senior Note)


Signature Guarantee:






<PAGE>   15



                       Option of Holder to Elect Purchase


                  If you want to elect to have this Senior Note purchased by the
Company pursuant to Section 4.7 or 4.9 of the Indenture, check the box below:

                        Section 4.7                        Section 4.9

                  If you want to elect to have only part of the Senior Note
purchased by the Company pursuant to Section 4.7 or Section 4.9 of the
Indenture, state the amount you elect to have purchased (must be an integral
multiple of $1,000): $__________________

Date:                                    Your Signature:
     -----------------------
                                         (Sign exactly as your name appears on 
- ----------------------------             the Senior Note)

                                         Social Senior Note or
                                         Tax Identification No.:
                                                                 -------------
- ----------------


Signature Guarantee:







<PAGE>   16


                                   SCHEDULE A

                   CHANGES IN PRINCIPAL AMOUNT OF SENIOR NOTE

                  The following changes in the principal amount of this Global
Note have been recorded:

<TABLE>
<CAPTION>

                                                                          
                         Amount of decrease      Amount of increase      Principal Amount of
                                in                       in                this Global Note          Signature of
                        Principal Amount of     Principal Amount of         following such        authorized officer
Date of Transaction      this Global Note        this Global Note        decrease(or increase)         of Trustee
- -------------------    ---------------------    --------------------    ----------------------    ------------------
<S>                    <C>                      <C>                     <C>                        <C>

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------

- --------------------------------------------------------------------------------------------------------------------
</TABLE>


<PAGE>   1
                                                                     EXHIBIT 4.5
================================================================================




                             DI INDUSTRIES, INC.

                                     AND

                                 GUARANTORS


                                $175,000,000
                        8-7/8% Senior Notes due 2007




                          ________________________


                                  INDENTURE



                          Dated as of June 27, 1997



                          ________________________




                  TEXAS COMMERCE BANK NATIONAL ASSOCIATION

                                   Trustee



================================================================================


<PAGE>   2


                               CROSS-REFERENCE

Reconciliation and tie between The Trust Indenture Act as amended, and The
Indenture dated as of June 27,1997.

         TIA                                             Indenture
       Section                                            Section
       -------                                            -------
                                                   
       310(a)(1)    . . . . . . . . . . . . . . . .       7.10
          (a)(2)    . . . . . . . . . . . . . . . .       7.10
          (a)(3)    . . . . . . . . . . . . . . . .       N.A.
          (a)(4)    . . . . . . . . . . . . . . . .       N.A.
          (a)(5)    . . . . . . . . . . . . . . . .       7.10 
          (b)       . . . . . . . . . . . . . . . .       7.08; 7.10
          (c)       . . . . . . . . . . . . . . . .       N.A.
       311(a)       . . . . . . . . . . . . . . . .       7.11
          (b)       . . . . . . . . . . . . . . . .       7.11
          (c)       . . . . . . . . . . . . . . . .       N.A.
       312(a)       . . . . . . . . . . . . . . . .       2.07
          (b)       . . . . . . . . . . . . . . . .       12.06
          (c)       . . . . . . . . . . . . . . . .       12.06
       313(a)       . . . . . . . . . . . . . . . .       7.06
          (b)(1)    . . . . . . . . . . . . . . . .       N.A.
          (b)(2)    . . . . . . . . . . . . . . . .       7.06 
          (c)       . . . . . . . . . . . . . . . .       7.06, 12.05 
          (d)       . . . . . . . . . . . . . . . .       7.06
       314(a)       . . . . . . . . . . . . . . . .       4.02; 4.20; 
                                                          12.05
          (b)       . . . . . . . . . . . . . . . .       N.A.  
          (c)(1)    . . . . . . . . . . . . . . . .       12.01, 12.02 
          (c)(2)    . . . . . . . . . . . . . . . .       12.01; 12.02 
          (c)(3)    . . . . . . . . . . . . . . . .        N.A.  
          (d)       . . . . . . . . . . . . . . . .        N.A.
          (e)       . . . . . . . . . . . . . . . .        12.01; 12.02
          (f)       . . . . . . . . . . . . . . . .        N.A.
       315(a)       . . . . . . . . . . . . . . . .        7.01 
          (b)       . . . . . . . . . . . . . . . .        4.20; 7.05; 12.02 
          (c)       . . . . . . . . . . . . . . . .        7.01 
          (d)       . . . . . . . . . . . . . . . .        7.01 
          (e)       . . . . . . . . . . . . . . . .        6.11
       316(a)(last sentence)  . . . . . . . . . . .        2.09 
          (a)(1)(A) . . . . . . . . . . . . . . . .        6.05 
          (a)(1)(B) . . . . . . . . . . . . . . . .        6.04 
          (a)(2)    . . . . . . . . . . . . . . . .        N.A.  
          (b)       . . . . . . . . . . . . . . . .        6.07 
          (c)       . . . . . . . . . . . . . . . .        10.05
       317(a)(1)    . . . . . . . . . . . . . . . .        6.03; 6.08
          (a)(2)    . . . . . . . . . . . . . . . .        6.09
          (b)       . . . . . . . . . . . . . . . .        2.04
       318(a)       . . . . . . . . . . . . . . . .        12.04




                                      1
<PAGE>   3





                          N.A. Means Not Applicable.

- --------------------------------           
Note:  This Cross-Reference Table shall not, for any purposes, be deemed to be 
part of this Indenture.







                                      2

<PAGE>   4

                               TABLE OF CONTENTS


                                                                            Page
                                                                            ----
                                                          

ARTICLE 1    Definitions and Incorporation by Reference . . . . . . . . . .   1
    SECTION 1.01.    Definitions  . . . . . . . . . . . . . . . . . . . . .   1
    SECTION 1.02.    Incorporation by Reference of Trust Indenture Act  . .  21
    SECTION 1.03     Rules of Construction  . . . . . . . . . . . . . . . .  21

ARTICLE 2    The Securities . . . . . . . . . . . . . . . . . . . . . . . .  22
    SECTION 2.01.    Form and Dating  . . . . . . . . . . . . . . . . . . .  22
    SECTION 2.02.    Execution and Authentication . . . . . . . . . . . . .  23 
    SECTION 2.03.    Registrar and Paying Agent . . . . . . . . . . . . . .  23 
    SECTION 2.04.    Paying Agent To Hold Money in Trust  . . . . . . . . .  24 
    SECTION 2.05.    Global Securities  . . . . . . . . . . . . . . . . . .  24 
    SECTION 2.06.    Transfer and Exchange  . . . . . . . . . . . . . . . .  24 
    SECTION 2.07.    Holder Lists . . . . . . . . . . . . . . . . . . . . .  24 
    SECTION 2.08.    Replacement Securities . . . . . . . . . . . . . . . .  24 
    SECTION 2.09.    Outstanding Securities . . . . . . . . . . . . . . . .  24 
    SECTION 2.10.    Temporary Securities . . . . . . . . . . . . . . . . .  24 
    SECTION 2.11.    Cancellation . . . . . . . . . . . . . . . . . . . . .  24 
    SECTION 2.12.    Payment of Interest: Interest Rights Preserved . . . .  24
    SECTION 2.13.    Authorized Denominations . . . . . . . . . . . . . . .  24 
    SECTION 2.14.    CUSIP Numbers  . . . . . . . . . . . . . . . . . . . .  24

ARTICLE 3  Redemption . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
    SECTION 3.01.    Notices to Trustee . . . . . . . . . . . . . . . . . .  24
    SECTION 3.02.    Selection of Securities To Be Redeemed . . . . . . . .  24
    SECTION 3.03.    Notice of Redemption . . . . . . . . . . . . . . . . .  24
    SECTION 3.04.    Effect of Notice of Redemption . . . . . . . . . . . .  24
    SECTION 3.05.    Deposit of Redemption Price  . . . . . . . . . . . . .  24
    SECTION 3.06.    Securities Redeemed in Part  . . . . . . . . . . . . .  24
    SECTION 3.07.    Optional Redemption  . . . . . . . . . . . . . . . . .  24


ARTICLE 4    Cpvenants  . . . . . . . . . . . . . . . . . . . . . . . . . .  24
    SECTION 4.01.    Payments of Securities . . . . . . . . . . . . . . . .  24
    SECTION 4.02.    Commission Reports . . . . . . . . . . . . . . . . . .  24
    SECTION 4.03.    Limitation on Indebtedness  . . . . . .. . . . . . . .  24
    SECTION 4.04.    Limitation on  Subsidiary Indebtedness and 
                       Preferred Stock  . . . . . . . . . . . . . . . . . .  24
    SECTION 4.05.    Limitation on Restricted Payments. . . . . . . . . . .  24
    SECTION 4.06.    Limitation on Dividends and  Other Payment
                       Restrictions Affecting Subsidiaries  . . . . . . . .  24


                                      i
<PAGE>   5





    SECTION 4.07.    Limitation on Asset Sales . . . . . . . . . . . . . . 24
    SECTION 4.08.    Limitation on Transactions with
                      Affiliates . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 4.09.    Change of Control . . . . . . . . . . . . . . . . . . 24
    SECTION 4.10.    Limitation on Liens                                   24
    SECTION 4.11.    Limitation on Guarantees by Guarantors  . . . . . . . 24
    SECTION 4.12.    Unrestricted Subsidiaries . . . . . . . . . . . . . . 24
    SECTION 4.13.    Limitation on Sale and Lease-Back Transactions. . . . 24
    SECTION 4.14.    Limitation on Line of Business  . . . . . . . . . . . 24
    SECTION 4.15.    Maintenance of Office or Agency . . . . . . . . . . . 24
    SECTION 4.16.    Money for the Security Payments to be Held in Trust . 24
    SECTION 4.17.    Corporate Existence . . . . . . . . . . . . . . . . . 24
    SECTION 4.18.    Maintenance of Property . . . . . . . . . . . . . . . 24
    SECTION 4.19.    Payment of Taxes and Other Claims . . . . . . . . . . 24
    SECTION 4.20.    Compliance Certificate; Notice of Default
                      or Event of Default  . . . . . . . . . . . . . . . . 24
    SECTION 4.21.    Further Instruments and Acts  . . . . . . . . . . . . 24
    SECTION 4.22.    Prohibition on Company and Guarantors
                      Becoming Investment Companies  . . . . . . . . . . . 24
    SECTION 4.23.    Stay, Extension and Usury Laws  . . . . . . . . . . . 24

ARTICLE 5    Consolidation, Merger, Conveyance, Lease or Transfer  . . . . 24
    SECTION 5.01.    Consolidation, Merger, Conveyance, Lease
                       or Transfer . . . . . . . . . . . . . . . . . . . . 24
    SECTION 5.02.    Officers Certificate and Opinion of Counsel . . . . . 24
    SECTION 5.03.    Substitution of Surviving Entity  . . . . . . . . . . 24

ARTICLE 6  Defaults and Remedies . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 6.01.    Events of Default . . . . . . . . . . . . . . . . . . 24
    SECTION 6.02.    Acceleration  . . . . . . . . . . . . . . . . . . . . 24
    SECTION 6.03.    Other Remedies  . . . . . . . . . . . . . . . . . . . 24
    SECTION 6.04.    Waiver of Past Defaults . . . . . . . . . . . . . . . 24
    SECTION 6.05.    Control by Majority . . . . . . . . . . . . . . . . . 24
    SECTION 6.06.    Limitation on Suits . . . . . . . . . . . . . . . . . 24
    SECTION 6.07.    Rights of Holders to Receive Payment  . . . . . . . . 24
    SECTION 6.08.    Collection Suit by Trustee  . . . . . . . . . . . . . 24
    SECTION 6.09.    Trustee May File Proofs of Claim  . . . . . . . . . . 24
    SECTION 6.10.    Priorities  . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 6.11.    Undertaking for Costs . . . . . . . . . . . . . . . . 24
    SECTION 6.12.    Restoration of Rights and Remedies  . . . . . . . . . 24
    SECTION 6.13.    Rights and Remedies Cumulative  . . . . . . . . . . . 24
    SECTION 6.14.    Delay or Omission Not Waiver  . . . . . . . . . . . . 24

ARTICLE 7  Trustee . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 7.01.    Duties of Trustee . . . . . . . . . . . . . . . . . . 24
    SECTION 7.02.    Rights of Trustee . . . . . . . . . . . . . . . . . . 24
    SECTION 7.03.    Individual Rights of Trustee  . . . . . . . . . . . . 24




                                      ii
      

<PAGE>   6





    SECTION 7.04.    Trustee's Disclaimer  . . . . . . . . . . . . . . . . 24
    SECTION 7.05.    Notice of Defaults  . . . . . . . . . . . . . . . . . 24
    SECTION 7.06.    Reports by Trustee to Holders . . . . . . . . . . . . 24
    SECTION 7.07.    Compensation and Indemnity  . . . . . . . . . . . . . 24
    SECTION 7.08.    Replacement of Trustee  . . . . . . . . . . . . . . . 24
    SECTION 7.09.    Successor Trustee by Merger . . . . . . . . . . . . . 24
    SECTION 7.10.    Eligibility; Disqualification . . . . . . . . . . . . 24
    SECTION 7.11.    Preferential Collection of Claims . . . . . . . . . .
                     Against Company . . . . . . . . . . . . . . . . . . . 24

ARTICLE 8  Satisfaction and Discharge. . . . . . . . . . . . . . . . . . . 24
    SECTION 8.01.    Satisfaction and Discharge  . . . . . . . . . . . . . 24
    SECTION 8.02.    Application of Trust Money  . . . . . . . . . . . . . 24
    SECTION 8.03.    Repayment to the Company. . . . . . . . . . . . . . . 24
    SECTION 8.04.    Reinstatement . . . . . . . . . . . . . . . . . . . . 24
                                                                 
ARTICLE 9    Defeasance. . . . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 9.01.    Company s Option to  Effect Defeasance or 
                      Covenant Defeasance  . . . . . . . . . . . . . . . . 24
    SECTION 9.02.    Defeasance and Discharge. . . . . . . . . . . . . . . 24
    SECTION 9.03.    Covenant Defeasance . . . . . . . . . . . . . . . . . 24
    SECTION 9.04.    Conditions to Defeasance or Covenant
                      Defeasance . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 9.05.    Deposited Money and U.S. Government        
                      Obligations to be Held in Trust;          
                      Miscellaneous Provisions . . . . . . . . . . . . . . 24
    SECTION 9.06.    Repayment to Company. . . . . . . . . . . . . . . . . 24
    SECTION 9.07.    Reinstatement . . . . . . . . . . . . . . . . . . . . 24


ARTICLE 10    Amendments . . . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 10.01.   Without Consent of Holders. . . . . . . . . . . . . . 24
    SECTION 10.02.   With Consent of Holders . . . . . . . . . . . . . . . 24
    SECTION 10.03.   Effect of Supplemental Indentures . . . . . . . . . . 24
    SECTION 10.04.   Compliance with Trust Indenture Act . . . . . . . . . 24
    SECTION 10.05.   Revocation and Effect of Consents and
                     Waivers . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 10.06.   Notation on or Exchange of Securities . . . . . . . . 24
    SECTION 10.07.   Trustee To Execute Supplemental Indentures  . . . . . 24
    SECTION 10.08.   Payment for Consent . . . . . . . . . . . . . . . . . 24
                                                                
ARTICLE 11    Guarantees . . . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 11.01.   Guarantees  . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 11.02.   Limitation on Liability . . . . . . . . . . . . . . . 24
    SECTION 11.03.   Execution and Delivery of Guarantees  . . . . . . . . 24
    SECTION 11.04.   When a Guarantor May Merge, etc.  . . . . . . . . . . 24
    SECTION 11.05.   No Waiver . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 11.06.   Modification  . . . . . . . . . . . . . . . . . . . . 24
    SECTION 11.07.   Release of Guarantor  . . . . . . . . . . . . . . . . 24




                                     iii

<PAGE>   7
    SECTION 11.08     Execution of Supplemental Indenture for Future
                        Guarantors . . . . . . . . . . . . . . . . . . . . . 24 

ARTICLE 12    Miscellaneous  . . . . . . . . . . . . . . . . . . . . . . . . 24
    SECTION 12.01.    Compliance Certificates and Opinions . . . . . . . . . 24 
    SECTION 12.02.    Form of Documents Delivered to Trustee . . . . . . . . 24 
    SECTION 12.03.    Acts of Holders  . . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.04.    Trust Indenture Act Controls . . . . . . . . . . . . . 24 
    SECTION 12.05.    Notices  . . . . . . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.06.    Communication by Holders with Other Holders. . . . . . 24 
    SECTION 12.07.    Rules  by  Trustee,   Paying  Agent   and      
                      Registrar  . . . . . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.08.    Payments on Business Days  . . . . . . . . . . . . . . 24 
    SECTION 12.09.    GOVERNING LAW  . . . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.10.    No Recourse Against Others . . . . . . . . . . . . . . 24 
    SECTION 12.11.    Submission to Jurisdiction; Appointment of Agent 
                      for Service of Process; Waiver of Immunities . . . . . 24 
    SECTION 12.12.    Successors . . . . . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.13.    Multiple Originals . . . . . . . . . . . . . . . . . . 24 
    SECTION 12.14.    Table of Contents; Headings  . . . . . . . . . . . . . 24 
  
EXHIBIT A    Form of Global Security
EXHIBIT B    Form of Certificated Security
EXHIBIT C    Form of Supplemental Indenture

Schedule 1.01(a)    Indebtedness Existing on the Issue Date
Schedule 1.01(b)    Investments Existing on the Issue Date
Schedule 1.01(c)    Liens Existing on the Issue Date
Schedule 4.04       Subsidiary Indebtedness and Preferred Stock Existing
                      on the Issue Date





                                      iv
<PAGE>   8

        INDENTURE dated as of June 27, 1997, among DI Industries, Inc., a
Texas corporation (the "Company"), certain of the Company's subsidiaries
signatory hereto (each, a "Guarantor", collectively, the "Guarantors") and
Texas Commerce Bank National Association, a national banking association, as
trustee (the "Trustee").

        The Company, each Guarantor, jointly and severally, and the Trustee
agree as follows for the benefit of the other parties and for the equal and 
ratable benefit of the Holders of the Company's 8-7/8% Senior Notes Due 2007
(the "Securities"):

                                   ARTICLE 1

                   Definitions and Incorporation by Reference

           SECTION 1.01.  Definitions.

        "Acquired Indebtedness" means, with respect to any specified Person,
Indebtedness of any other Person existing at the time such other Person merged
with or into or became a subsidiary of such specified Person, including 
Indebtedness incurred in connection with, or in contemplation of, such other
Person merging with or into or becoming a subsidiary of such specified
Person, but excluding Indebtedness which is extinguished, retired or repaid
in connection with such other Person merging with or into or becoming a
subsidiary of such specified Person.

        "Act", when used with respect to any Holder, has the meaning set forth
in Section 12.03.

        "Adjusted Net Assets" of a Guarantor at any date means the amount by 
which the fair value of the assets and Property of such Guarantor exceeds the
total amount of liabilities, including, without limitation, contingent
liabilities (after giving effect to all other fixed and contingent
liabilities incurred or assumed on such date), but excluding liabilities under
its Guarantee, of such Guarantor at such date.

        "Affiliate" of any specified Person means another Person directly
or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person. For purposes of this
definition, "control"  (including, with correlative meanings, the terms
"controlling", "controlled by" and "under common control with"), as used with 
respect to any Person, shall mean the possession, directly or indirectly, 
of the power to direct or cause the direction of the management or policies
of such Person, whether through the ownership  of voting securities, by 
agreement or  otherwise; provided, however,  that beneficial ownership of 10%
or more of the Voting Stock of a Person shall be deemed to be control.





                                       1
<PAGE>   9
            "Agent Member" has the meaning specified in Section 2.05(a).


            "Asset  Sale" means  any direct or  indirect sale,  conveyance,
  transfer,  lease or  other disposition (including,  without limitation,  by
  way  of merger  or consolidation  or by  means of  a Sale  and  Lease-Back
  Transaction)  by the Company or any  Subsidiary to any Person other  than the
  Company, a Guarantor or a Wholly Owned Subsidiary,  in one transaction, or  a
  series of related  transactions, of (i) any  Capital Stock of  any Subsidiary
  (except for  directors' qualifying  shares  or certain  minority interests
  sold to  other Persons solely  due to local law  requirements that there be
  more than one stockholder,  but which are not in excess of what is required
  for such purpose), or (ii) any  other Property or assets  of the Company or
  any Subsidiary, other than (A) sales  of drill-string components and obsolete
  or worn  out equipment in the ordinary course of business or other  assets
  that, in  the Company's  reasonable judgment, are  no longer used or  useful
  in  the conduct of  the business of  the Company and  its Subsidiaries), (B)
  any drilling contract,  charter or  other lease  of Property or other  assets
  entered into  by the Company  or any Subsidiary in the  ordinary course of
  business,  other  than  any Bargain  Purchase  Contract, (C)  a Restricted
  Payment  or  Restricted Investment permitted  under  the  provisions  of
  Section  4.05  of  this  Indenture,  (D)  a  Change  of Control,  (E)  a
  consolidation,  merger, continuance  or  the disposition  of all  or
  substantially  all of  the assets  of the Company and the  Subsidiaries,
  taken as a whole,  in compliance with  the provisions of  Section 5.01 of
  this Indenture, (F) any  trade or exchange by the Company or any Subsidiary
  of one or more  drilling rigs for one or more other drilling rigs  of like
  kind owned  or held by another  Person, provided that (x)  the Fair Value  of
  the rig or  rigs traded or exchanged by the Company or such Subsidiary
  (including  cash or cash equivalents to be delivered by the  Company or such
  Subsidiary) is  reasonably equivalent to the  Fair Value of the  drilling rig
  or rigs  (together with cash  or cash equivalents  to be received  by the
  Company or  such Subsidiary) or other assets as determined  by written
  appraisal by a nationally  (or industry) recognized investment  banking firm
  or appraisal firm  and (y) such exchange is approved by  a majority of the
  disinterested directors of the Company.  An Asset Sale  shall include the
  requisition of  title to, seizure of or  forfeiture of any Property or
  assets, or any actual or constructive total loss or  an agreed or compromised
  total loss of  any Property or assets.

            "Asset Sale Offer" has the meaning specified in Section 4.07(b).

            "Asset Sale Offer Purchase Date" has the meaning specified in 
Section 4.07(c).

            "Asset Sale Offer Purchase Price" has the meaning specified in 
Section 4.07(b).

            "Attributable Indebtedness" in respect of  a Sale  and Lease-Back
  Transaction  means, at any  date of determination, the  present value
  (discounted  at  the interest  rate  borne  by the  Securities,  compounded
  annually) of the total  obligations of the lessee for  rental payments during
  the remaining term of  the lease (or  to the  first date  on which the
  lessee is  permitted to terminate  such lease  without the payment  of a
  penalty) included in such Sale and Lease-Back Transaction  (including any
  period for which such  lease has been extended).

            "Average Life" means, as  of any date,  with respect to  any debt
  security,  the quotient obtained  by dividing (i) the sum of the products of
  (x) the number of years from such date to





                                       2
<PAGE>   10

  the date  of each  scheduled principal  payment (including  any sinking  fund
  or  mandatory redemption  payment requirements) of such  debt security
  multiplied  in each  case by (y) the  amount of such principal  payment by
  (ii) the sum of all such principal payments.

            "Bank Credit Facility" means the $50,000,000  Amended and
  Restated Senior  Secured Revolving Credit Agreement  dated December  31,
  1996,  as amended  and restated  as of  April 30, 1997,  among the  Company
  and Drillers,  Inc.,  as  co-borrowers, DI  International,  Inc.,  as
  guarantor,  the  lending institutions  party thereto, Bankers Trust Company,
  as agent and administrative  agent, and ING (US)  Capital Corporation, as co-
  agent and documentation agent, as from time to time amended.

            "Bargain Purchase Contract" means a drilling contract, charter or
  lease that provides for acquisition of Property  by the other party to such
  agreement during  or at the end of  the term thereof for less than Fair
  Market Value thereof at the time such right to acquire such Property is
  granted.

            "Board of Directors" means the Board of Directors of the Company or
  any Subsidiary, as applicable,  or any committee thereof duly authorized to
  act on behalf of such Board.

            "Board Resolution" means  a copy of a resolution certified by  the
  Secretary or an Assistant Secretary of the Company  or any Subsidiary, as
  applicable, to  have been duly adopted by  the Board of Directors and to be
  in full force and effect on the date of such certification, and delivered to
  the Trustee.

            "Business Day" means each Monday, Tuesday, Wednesday, Thursday  and
  Friday which is not a day on which banking  institutions are authorized or
  obligated by  law or executive order or regulation to close in The City of
  New York and Houston, Texas  and, with respect to any payment of  cash or
  delivery of  securities, the place of such payment or delivery.

            "Capital Lease Obligation" means, at any time as to any Person with
  respect to any Property leased by such  Person as lessee, the amount of the
  liability  with respect to such lease that would  be required at such time to
  be capitalized and accounted for as a capital lease on the balance sheet of
  such Person prepared in accordance with GAAP.

            "Capital Stock" in any Person  means  any  and  all  shares,
  interests,  partnership  interests, participations or other equivalents in
  the  equity interest (however designated) in such Person and any rights
  (other than debt  securities convertible into an  equity interest), warrants
  or options to acquire any equity interest in such Person.


            "Cash Proceeds" means,  with respect  to any Asset  Sale by  any
  Person,  the aggregate consideration received for such Asset  Sale by such
  Person in the form of cash or cash equivalents  (including any amounts of
  insurance or other proceeds  received in  connection with  an Asset  Sale of
  the  type described  in the  last sentence  of the  definition thereof),
  including payments  in  respect of  deferred payment  obligations when
  received in the form of  cash or cash equivalents (except to the extent that
  such obligations  are financed or sold with recourse to such Person or any
  subsidiary thereof).





                                       3
<PAGE>   11

            "Certificated Security" has the meaning specified in Section
  2.01(b).

            "Change of Control" means (i) a determination  by the Company that
  any Person or group (as  defined in Section 13(d)(3) or 14(d)(2)  of the
  Exchange  Act) has  become the direct or  beneficial owner (as defined  in
  Rule 13d-3  under the Exchange Act) of  more than 50% of the  Voting Stock of
  the Company other than Permitted Holders; (ii) the  Company is merged with or
  into or consolidated with  another corporation and,  immediately after
  giving effect  to  the merger  or consolidation,  less than  50% of  the
  outstanding  voting securities entitled  to vote  generally in  the  election
  of  directors or  persons  who serve  similar functions  of  the surviving or
  resulting entity  are then beneficially owned  (within the meaning  of Rule
  13d-3 of  the Exchange Act)  in  the  aggregate  by  (x) the  stockholders
  of  the  Company  immediately  prior  to  such  merger  or consolidation, or
  (y) if  the record date has been  set to determine the stockholders of the
  Company entitled to vote on  such merger or consolidation,  the stockholders
  of the Company as of such  a record date; (iii) the Company, either
  individually  or in conjunction  with one  or more Subsidiaries,  sells,
  conveys, transfers  or leases,  or the  Subsidiaries sell, convey, transfer
  or lease, all or  substantially all of the  assets of the Company or  the
  Company  and the Subsidiaries,  taken as  a whole  (either in one
  transaction or  a series of related transactions), including Capital Stock of
  the Subsidiaries, to any Person (other than a Wholly  Owned Subsidiary); (iv)
  the liquidation or dissolution of the  Company; or (v) the first day on
  which a majority of the individuals who constitute the Board of Directors of
  the Company are not Continuing Directors.

            "Change of Control Offer" has the meaning specified in 
Section 4.09(a).

            "Change of Control Payment Date" has the meaning specified in 
Section 4.09(b)(ii).

            "Change of Control Purchase Price" has the meaning specified in 
Section 4.09(a).

            "Commission"  means the  United  States Securities  and  Exchange
  Commission,  as  from  time to  time constituted, created under the Exchange
  Act, or if at any  time after the execution of  this instrument, such
  Commission  is not existing and performing  the duties now assigned to  it
  under the Trust Indenture Act, then the body performing such duties at such
  time.

            "Company" means the Person named as  the "Company" in the first
  paragraph of this Indenture, until  a successor  Person  shall have  become
  such  pursuant to  the  applicable  provisions  of  this Indenture,  and
  thereafter "Company" shall mean such successor Person.

            "Consolidated Interest Coverage Ratio" means as  of the date  of the
  transaction  giving rise to  the need  to calculate the  Consolidated
  Interest Coverage Ratio  (the  "Transaction Date"),  the ratio  of (i) the
  aggregate amount  of EBITDA of the Company and  its consolidated Subsidiaries
  for  the four fiscal quarters for which financial  information in respect
  thereof is  available immediately prior to  the applicable Transaction
  Date (the  "Determination Period") to  (ii) the aggregate Consolidated
  Interest Expense  of the Company and its consolidated Subsidiaries  that is
  anticipated to accrue during a  period consisting of the  fiscal quarter in
  which the  Transaction Date occurs  and the three  fiscal quarters
  immediately  subsequent thereto (based  upon the pro forma amount and
  maturity of, and interest payments in respect of,





                                       4
<PAGE>   12

  Indebtedness of the Company   and its consolidated  Subsidiaries expected by
  the Company to be  outstanding on the Transaction  Date), assuming  for the
  purposes of  this measurement  the continuation  of market  interest rates
  prevailing  on the  Transaction  Date and  base  interest rates  in respect
  of floating  interest  rate obligations  equal to  the base  interest rates
  on such  obligations in  effect as  of the  Transaction  Date, provided that
  if  the Company  or any  of  its consolidated  Subsidiaries is  a party  to
  any  Interest  Swap Obligation that would  have the effect of changing the
  interest rate on any Indebtedness of the Company or any of its  consolidated
  Subsidiaries  for such  four-quarter period  (or a  portion thereof),  the
  resulting  rate shall  be used  for such  four-quarter  period  or portion
  thereof; provided,  further, that  any Consolidated Interest Expense of the
  Company with respect to Indebtedness  incurred or retired by the Company or
  any of its Subsidiaries during  the fiscal quarter in  which the Transaction
  Date occurs shall be  calculated as if  such debt was incurred  or retired on
  the first  day of the  fiscal quarter in which  the Transaction Date  occurs;
  provided,  further, that  if the transaction  giving rise to  the need to
  calculate  the Consolidated Interest Coverage Ratio would have the effect of
  increasing or decreasing EBITDA in the future and if such  increase or
  decrease is readily quantifiable and is  attributable to such transaction,
  EBITDA shall be calculated on a  pro forma basis as  if such transaction had
  occurred  on the first day of the four fiscal  quarters referred to in clause
  (i) of this  definition, and if,  during the same four  fiscal quarters, (x)
  the  Company or any of  its consolidated Subsidiaries shall  have engaged in
  any Asset Sale, EBITDA for such period shall  be reduced by an amount equal
  to the  EBITDA (if  positive), or  increased by  an  amount equal  to the
  EBITDA (if  negative), directly attributable to the assets which are the
  subject of such Asset Sale for such  period calculated on a pro forma basis
  as if such Asset Sale and  any related retirement of  Indebtedness had
  occurred on  the first day of  such period or  (y) after the Issue Date,  the
  Company or  any of its consolidated  Subsidiaries shall have  acquired any
  material assets  other than  in the ordinary  course of  business, EBITDA
  and Consolidated Interest  Expense shall be calculated  on a pro forma  basis
  as if such acquisition had  occurred on the first day of such period.

            "Consolidated Interest Expense" means, with respect to any Person
  for any period, without duplication (A) the sum of (i) the aggregate amount
  of cash and noncash interest expense  (including capitalized interest) of
  such Person and its subsidiaries for  such period as determined on a
  consolidated basis in accordance  with GAAP in  respect of Indebtedness
  (including, without limitation,  (v) any amortization  of debt discount,  (w)
  net costs  associated  with Interest  Swap  Obligations (including  any
  amortization  of discounts),  (x)  the interest portion of  any deferred
  payment obligation  calculated in  accordance with  the effective  interest
  method, (y)  all accrued  interest and (z)  all commissions,  discounts and
  other  fees and  charges owed  with respect to  letters of credit, bankers
  acceptances or  similar facilities) paid or  accrued, or scheduled to be paid
  or  accrued, during such  period; (ii) dividends  on Preferred Stock  or
  Redeemable Stock  of such  Person (and  Preferred Stock or Redeemable Stock
  of  its subsidiaries if paid  to a Person other  than such Person or its
  subsidiaries)  declared and payable in cash; (iii) the  portion of any rental
  obligation of such Person or its subsidiaries in respect of any  Capital
  Lease Obligation allocable to interest expense in accordance  with GAAP; (iv)
  the portion  of any rental obligation of such Person or its subsidiaries in
  respect  of any Sale and Lease-Back Transaction  allocable to interest
  expense (determined as if  such were treated as  a Capital Lease Obligation);
  and (v) to the extent any debt of any other Person is guaranteed by





                                       5
<PAGE>   13
  such  Person or any  of its subsidiaries,  the aggregate amount of interest
  paid, accrued or  scheduled to be paid or  accrued, by  such other Person
  during  such period  attributable to any  such debt,  less (B)  to the extent
  included in (A) above,  amortization or write-off  of deferred  financing
  costs of such  Person and its subsidiaries during  such period  and any
  charge  related or  any premium or  penalty paid  in connection  with
  redeeming or retiring any  Indebtedness of such Person  and its subsidiaries
  prior to its stated  maturity; in the case  of both (A)  and (B)  above,
  after  elimination of  intercompany accounts among  such Person and  its
  subsidiaries  and  as  determined  in accordance  with  GAAP.   For  purposes
  of  clause (ii) above,  dividend requirements attributable to any Preferred
  Stock  or Redeemable Stock shall be deemed to be an amount equal  to the
  amount  of dividend  requirements  on such  Preferred  Stock or  Redeemable
  Stock  times a  fraction,  the numerator of which is the amount of such
  dividend requirements, and  the denominator of which is one minus the
  applicable  combined federal, state,  local and foreign income  tax rate of
  the Company  and its Subsidiaries (expressed as a decimal),  on a
  consolidated basis, for the fiscal  year immediately preceding the date of
  the transaction giving rise to the need to calculate Consolidated Interest
  Expense.

            "Consolidated Net Income" of any Person means, for any period, the
  aggregate net income (or net  loss, as the case may be)  of such Person and
  its  subsidiaries for such period on  a consolidated basis, determined in
  accordance with  GAAP, provided that there  shall be excluded  therefrom,
  without duplication,  (i) any net income of  any Unrestricted  Subsidiary,
  except  that the  Company's or  any Subsidiary's  interest in the  net income
  of such Unrestricted  Subsidiary for such period  shall be included  in such
  Consolidated Net  Income up to the  aggregate amount  of cash  or cash
  equivalents actually  distributed by  such Unrestricted  Subsidiary during
  such period to the Company or a Subsidiary as a dividend or other
  distribution, (ii) gains and losses, net  of taxes,  from Asset Sales or
  reserves relating thereto, (iii) the  net income of any Person that is not a
  subsidiary or that  is accounted for by the equity method of  accounting
  which shall be included only to the extent of the  amount of dividends or
  distributions  paid to such Person or its subsidiaries,  (iv) items (but not
  loss  items) classified as extraordinary, unusual or  nonrecurring (other
  than the  tax benefit, if any, of the utilization of net  operating loss
  carryforwards or  alternative minimum tax credits),  (v) the net income (but
  not net loss) of any Person acquired by such  specified Person or any of
  its subsidiaries in a pooling-of-interests  transaction for any period prior
  to the date of such acquisition,  (vi) any gain or loss, net of taxes,
  realized  on the termination of  any employee pension  benefit plan,  (vii)
  the net income (but not net loss)  of any  subsidiary of  such specified
  Person to the extent that the transfer  to that  Person of that income is
  not  at  the  time  permitted,  directly  or  indirectly,  by any  means
  (including by dividend, distribution, advance or loan or  otherwise), by
  operation of the terms of its charter or any agreement with a Person  other
  than  with such  specified Person,  instrument  held  by a  Person other
  than by  such specified Person, judgment, decree,  order, statute, law, rule
  or  governmental regulations applicable to such subsidiary or its
  stockholders,  except for  any dividends  or distributions  actually paid  by
  such  subsidiary to  such Person, and (viii) with regard to a  non-Wholly
  Owned Subsidiary, any aggregate net income (or loss) in  excess of such
  Person's  or such subsidiary's  pro rata share of  such non-Wholly Owned
  Subsidiary's net income  (or loss).





                                       6
<PAGE>   14

            "Consolidated Net Worth" of any  Person means,  as of  any date,
  the  sum of the Capital Stock and additional  paid-in capital  plus
  retained earnings (or  minus accumulated  deficit)  of  such Person  and its
  subsidiaries on a consolidated basis at such date,  each item determined in
  accordance with GAAP, less amounts attributable to Redeemable Stock of such
  Person or any of its subsidiaries.

            "Continuing Director" means an individual who (i) is a  member
  of  the Board  of Directors  of the Company and (ii)  either (A) was a member
  of the Board of Directors  of the Company on  the Issue Date or (B) whose
  nomination for election or election to the  Board of Directors of the Company
  was approved by vote of at least  a majority of the directors then still in
  office who were either directors  on the Issue Date or whose election or
  nomination for election was previously so approved.

            "Corporate Trust Office" means the office of  the  Trustee at
  which  at any  particular  time its corporate trust business shall  be
  principally administered, which  office at the date of  execution of this
  Indenture is located at 600 Travis Street, Suite 1150, Houston, Texas 77002.

            "Covenant Defeasance" has the meaning specified in Section 9.03.

            "Currency Hedge Obligations" means, at any time as to any Person,
  the obligations of  such Person at such  time which were incurred in the
  ordinary course of business pursuant to any  foreign currency exchange
  agreement, option or future contract or  other similar agreement or
  arrangement designed to protect against or manage such Person's or any of its
  subsidiaries  exposure to fluctuations in foreign currency exchange rates.

            "Default" means any  event, act  or condition  the occurrence  of
  which is, or after notice  or the passage time or both would be, an Event
  of Default.

            "Defaulted Interest" has the meaning specified in Section 2.12.

            "Defeasance" has the meaning specified in Section 9.02.

            "Depositary" means The Depository Trust Company, its nominees and
  their respective successors.

            "Determination Period" has the meaning  specified under clause (i) 
  of the definition of Consolidated Interest Coverage Ratio.

            "EBITDA" means, with respect to any Person for any period, the
  Consolidated Net Income of such Person for  such period, plus  to the extent
  reflected in the income statement of such Person  for such period from which
  Consolidated Net Income is determined, without duplication, (i) Consolidated 
  Interest Expense, (ii) income tax  expense, (iii)  depreciation expense,  
  (iv) amortization  expense, (v) any charge related to any premium or penalty 
  paid in connection with redeeming or retiring any Indebtedness prior to its 
  stated maturity, (vi) any other non-cash charges  and (vii) to the extent 
  not otherwise covered by the adjustments contained in the proviso to this 
  definition, non-recurring charges of approximately $6.1 million





                                       7
<PAGE>   15

  incurred during  1996 in  employment severance  costs, exit  costs
  attributable  to its  exiting Argentina  and Mexico  and other  non-recurring
  charges,  all as  described in  the Company's  Form 10-K  for the  year
  ended December 31, 1996 and minus,  to the extent reflected in  such income
  statement, any noncash  credits that had the effect of  increasing
  Consolidated Net Income  of such Person for such  period; provided that for
  purposes of  determining EBITDA with respect  to the Company,  Consolidated
  Net  Income shall exclude any  net income or loss for the year ended December
  31, 1996 associated with the Company's Argentine or Mexican divisions.

            "Event of Default" has the meaning specified in Section 6.01.

            "Excess Proceeds" has the meaning specified in Section 4.07(a).

            "Exchange Act" means the Securities and Exchange Act of 1934, as 
  amended.

            "Fair Market Value" means,  with respect to consideration received
  or to be received pursuant  to any transaction  by any Person,  the fair
  market value of  such consideration as  determined in good  faith by the
  Board of Directors of the Company.

            "Fair Value" means, with respect to any asset or  Property, the
  price which could be negotiated in  an arm's-length free market transaction,
  for cash, between a  willing seller and a willing buyer,  neither of whom is
  under undue pressure or compulsion to complete the transaction.

            "GAAP" means,  at  any date,  United  States generally  accepted
  accounting principles,  consistently applied, as  set  forth in  the opinions
  of  the  Accounting Principles  Board of  the  American Institute  of
  Certified Public Accountants ("AICPA") and statements  of the Financial
  Accounting Standards  Board, or in such other  statements  by  such other
  entity  as may  be  designated by  the  AICPA, that  are  applicable to  the
  circumstances  as of the date of determination; provided, however, that  all
  calculations made for purposes of determining  compliance with the provisions
  set forth in  this Indenture  shall utilize GAAP in  effect at the Issue
  Date.

            "Global Security" has the meaning specified in Section 2.01(b).

            "Grey Wolf" means Grey Wolf Drilling Company, a Texas corporation.

            "Grey Wolf Acquisition" means the agreement  to merge Grey  Wolf
  into Drillers, Inc. pursuant to an Agreement and Plan of Merger dated March 7,
  1997,  by and among the Company, Drillers, Inc.  and Grey Wolf, as such may 
  be amended to the Issue Date.

             "Guarantee" means an unconditional guaranty  of the Securities
  given by any  Subsidiary pursuant to the provisions of Article 11 of this
  Indenture.

            "Guarantor" means Drillers, Inc., DI International Inc. and  DI
  Energy Inc., each a Texas corporation and a Subsidiary, and each other
  Subsidiary of the Company that is required





                                       8
<PAGE>   16

  to guarantee the Company's Obligations  under the Securities and this
  Indenture  pursuant to the provisions of Article 11 of  this Indenture and
  any  other Subsidiary of the Company  that executes a supplemental  indenture
  in  which  such Subsidiary  agrees  to  guarantee the  Company's  Obligations
  under the  Securities  and  this Indenture.

            "Holder" means the Person in whose name a Security is registered on
  the Registrar's books.

            "incur" means, with respect to any Indebtedness or  other obligation
  of any Person, to create,  issue, suffer to exist, incur  (by conversion,
  exchange or  otherwise), assume, guarantee or  otherwise become  liable in
  respect of  such Indebtedness  or  other obligation  or the  recording,  as
  required  pursuant to  GAAP  or otherwise, of  any such Indebtedness  or
  obligation  on the  balance sheet  of such  Person (and "incurrence,"
  "incurred,"  "incurrable" and "incurring" shall have meanings correlative to
  the foregoing); provided that  a change in GAAP  that results in an
  obligation of such Person  that exists at  such time  becoming Indebtedness
  shall not be  deemed an incurrence of  such Indebtedness.  Indebtedness
  otherwise  incurred by a Person  before it becomes a Subsidiary shall be
  deemed to have been incurred at the time at which it becomes a Subsidiary.

            "Indebtedness" as applied to any Person means,  at any time, without
  duplication, whether recourse  is to all or a portion  of the assets of such
  Person,  and whether or not contingent, (i) any obligation  of such Person
  for  borrowed money; (ii) any obligation of  such Person evidenced by  bonds,
  debentures, notes or other similar  instruments,  including,  without
  limitation,  any  such  obligations  incurred  in  connection  with
  acquisition of  Property, assets  or businesses,  excluding accounts  payable
  made  in the  ordinary course  of business which  are  not more  than 90
  days  overdue or  which  are  being contested  in  good faith  and  by
  appropriate proceedings;  (iii) any obligation  of such Person  for all or
  any part of  the purchase price of Property or for  the cost of Property
  constructed or of improvements thereto (including any  obligation under or in
  connection with any letter of credit  related thereto), other than  accounts
  payable incurred in respect of Property and services purchased  in the
  ordinary course of business which are no more than  90 days overdue or  which
  are being contested in good  faith and by appropriate proceedings; (iv) any
  obligation of such Person upon  which interest charges are customarily  paid
  (other than accounts payable incurred in the ordinary course of business);
  (v)  any obligation of such Person  under conditional sale or  other title
  retention  agreements relating to purchased Property; (vi) any  obligation of
  such Person issued or assumed as the deferred  purchase price of Property
  (other than accounts  payable incurred in the ordinary course of  business
  which are no more than 90 days overdue  or which are being  contested in good
  faith  and by appropriate  proceedings); (vii)  any Capital Lease Obligation
  or  Attributable Indebtedness pursuant to any  Sale and Lease-Back
  Transaction of such Person; (viii)  any obligation  of any  other  Person
  secured by  (or for  which the  obligee thereof  has  an existing right,
  contingent  or otherwise, to be secured by)  any Lien on Property owned or
  acquired, whether or not any  obligation secured thereby has  been assumed,
  by such  Person; (ix) any obligation  of such Person  in respect  of  any
  letter  of  credit supporting  any  obligation  of any  other  Person; (x)
  the  maximum fixed repurchase price  of any Redeemable  Stock of such Person
  (or  if such Person  is a subsidiary,  any Preferred Stock of such Person);
  (xi) the notional





                                       9
<PAGE>   17

  amount  of any  Interest  Swap  Obligation  or  Currency  Hedge  Obligation
  of  such Person  at  the  time  of determination; and  (xii)  any  obligation
  which  is  in  economic  effect  a  guarantee,  regardless  of  its
  characterization  (other  than an  endorsement  in  the ordinary  course  of
  business), with  respect  to  any Indebtedness of  another Person,  to the
  extent guaranteed.    For purposes  of the  preceding sentence,  the maximum
  fixed repurchase  price of any  Redeemable Stock  or subsidiary  Preferred
  Stock that  does not have  a fixed  repurchase  price shall  be  calculated
  in accordance  with  the  terms  of  such  Redeemable Stock  or subsidiary
  Preferred Stock as if  such Redeemable Stock or subsidiary Preferred  Stock
  were repurchased on any date on  which Indebtedness shall be required to be
  determined pursuant to the  Indenture; provided, however, that  if such
  Redeemable  Stock or  subsidiary Preferred  Stock is  not then  permitted to
  be  repurchased, the repurchase price  shall be the book value of such
  Redeemable Stock or  subsidiary Preferred Stock.  The amount of Indebtedness
  of any Person at any date shall be  the outstanding balance at such date of
  all unconditional obligations as  described above and the  maximum liability
  of  any guarantees at such  date; provided that  for purposes  of calculating
  the amount of any  non-interest bearing or other discount  security, such
  Indebtedness shall be deemed to be  the principal amount thereof  that would
  be  shown on the balance  sheet of the  issuer dated such date  prepared in
  accordance with GAAP but that such security shall be deemed to have been
  incurred only on the date of the original issuance thereof.

            "Indenture"  means  this Indenture  as  originally  executed  or  as
  it may  from  time  to  time  be supplemented  or amended by one or more
  indentures supplemental hereto entered  into pursuant to the applicable
  provisions  hereof, including, for  all purposes of this  Indenture and  any
  such supplemental  indenture, the provisions of the  Trust Indenture Act that
  are deemed to be a part of and govern  this Indenture, and any such
  supplemental indenture, respectively.

            "Indrillers"  means INDRILLERS, L.L.C., a Michigan limited liability
  company  of which the Company is a member.

            "Interest Payment Date"  means the Stated Maturity  of an
  installment  of interest on the  Securities, which date shall be January 1
  and July 1 of each year.

            "Interest Swap Obligation"  means,  with respect to any Person, the
  obligation  of such Person pursuant to any  interest rate swap agreement,
  interest rate  cap, collar or floor  agreement or other similar agreement or
  arrangement  designed to protect against  or manage such  Person's or any of
  its subsidiaries' exposure  to fluctuations in interest rates.

            "Investment"  means,  with respect  to any  Person, any  direct,
  indirect or  contingent investment  in another Person,  whether  by  means
  of a  share  purchase, capital  contribution,  loan, advance  (other  than
  advances to  employees for  moving  and travel  expenses,  drawing  accounts
  and  similar expenditures  in  the ordinary  course of business) or similar
  credit  extension constituting Indebtedness of such  other Person, and any
  guarantee  of Indebtedness of any other Person;  provided that the term
  Investment  shall not include any transaction  involving the purchase  or
  other acquisition (including by  way of merger) of Property (including
  Capital Stock) by the  Company or any Subsidiary  in exchange for  Capital
  Stock (other than  Redeemable Stock) of the Company.  The amount of  any
  Person's Investment shall be the original cost  of such Investment to such
  Person, plus the cost of all additions thereto





                                       10
<PAGE>   18
  paid  by such Person, and minus the amount of  any portion of such Investment
  repaid to such Person in cash as a repayment of principal  or a return of
  capital, as the case  may be, but without  any other adjustments  for
  increases or decreases in value, or write-ups, writedowns,  or write-offs
  with respect to such  Investment.  In determining the amount of  any
  Investment involving a transfer of any Property or assets other  than cash,
  such Property or assets  shall be valued at its Fair Value at the time of
  such transfer  as determined in good faith by  the board  of directors (or
  comparable body) of  the Person making  such transfer.  The  Company shall be
  deemed to  make an "Investment" in the amount of the Fair Value of the Assets
  of  a Subsidiary at the time such Subsidiary is designated an Unrestricted
  Subsidiary.

            "Issue Date" means the date on which the  Securities are first
  authenticated and delivered under  this Indenture.

            "Joint Venture" means any Person (other than a Guarantor) designated
  as such by a Board Resolution  of the Company  and as to which  (i) the
  Company,  any Guarantor or any  Joint Venture owns less than  50% of the
  Capital  Stock of such Person; (ii) no  more than 10 unaffiliated  Persons
  own of record  any Capital Stock of such Person; (iii) at all times,  each
  such Person owns  the same proportion of each class of Capital  Stock of such
  Person outstanding  at such time;  (iv) no  Indebtedness of  such Person is
  or becomes outstanding  other than  Non-Recourse Indebtedness; (v) there
  exist  no consensual encumbrances  or restrictions on the ability of such
  Person to  (x) pay, directly or indirectly, dividends or  make any other
  distributions in  respect of its Capital Stock to the holders of its Capital
  Stock or (y) pay any Indebtedness or  other obligation owed to the holders of
  its Capital Stock or  (z) make any  Investment in the holders  of its Capital
  Stock, in each case other  than the types of consensual encumbrances or
  restrictions that  would be permitted under the provisions of Section 4.06 of
  this Indenture if such Person were a Subsidiary;  and (vi) the business
  engaged in by  such Person is a Related Business.

            "Lien"   means   any  mortgage,  pledge,   hypothecation,  charge,
  assignment,   deposit  arrangement, encumbrance, security  interest, lien
  (statutory or  other), or  preference,  priority or  other security  or
  similar  agreement  or  preferential  arrangement  of  any  kind  or  nature
  whatsoever  (including,  without limitation,  any agreement to  give or grant
  a Lien or any lease,  conditional sale or  other title retention agreement
  having substantially the same economic effect as any of the foregoing).

            "Maturity"  means  the date on which  the principal of a  Security
  becomes due and  payable as provided therein or  in  this  Indenture, whether
  at the  Stated Maturity  or the  Change  of Control  Payment Date  or
  purchase date established  pursuant to the terms of  this Indenture for an
  Asset  Sale Offer or by declaration of acceleration, call for redemption or
  otherwise.

            "Moody's"  means  Moody's Investor Service,  Inc., or, if  Moody's
  Investors Service,  Inc. shall cease rating the  specified  debt  securities
  and  such ratings  business  with  respect  thereto  shall  have  been
  transferred to a successor  Person, such successor  person; provided that  if
  Moody's Investors  Service, Inc.  ceases rating the specified debt securities
  and its ratings business with respect thereto shall not have  been
  transferred  to any successor  Person or  such successor  Person is  S&P,
  then   Moody's  shall mean  any other nationally recognized rating




                                       11
<PAGE>   19

  agency  (other than S&P)  that rates  the specified  debt securities selected
  in  good faith  by the  Board of Directors of the Company in a Board
  Resolution.

            "Net Available" Proceeds means, (a) as  to any Asset Sale  (other
  than a  Bargain Purchase Contract), the Cash Proceeds  therefrom, net of  all
  legal  and title  expenses, commissions and  other fees and  expenses
  incurred, and all  Federal, state, foreign, recording  and local taxes
  payable as  a consequence of such  Asset Sale, net of all payments made to
  any Person other  than the Company or a Subsidiary on  any Indebtedness which
  is secured by such assets,  in accordance with the terms of  any Lien upon or
  with respect to such  assets, or which  must by its terms, or in order to
  obtain a necessary consent to such Asset Sale, or by applicable law, be
  repaid out of the  proceeds from such  Asset Sale  and, as for any  Asset
  Sale by a  Subsidiary, net of the equity interest  in such  Cash Proceeds of
  any holder  of Capital  Stock of such Subsidiary  (other than  the Company,
  any other  Subsidiary or any Affiliate of the Company  or any such other
  Subsidiary) and (b) as to any Bargain Purchase Contract, an amount equal to
  (i) that  portion of the rental or other payment  stream arising under a
  Bargain Purchase Contract that represents an amount  in excess of the Fair
  Market Value of the rental or other payments  with respect to the pertinent
  Property or other asset and  (ii) the Cash Proceeds from the sale of  such
  Property or other asset,  net of the amount  set forth in  clause (a) above,
  in  each case as and when received.

            "Non-Recourse Indebtedness" means Indebtedness  or that portion  of
  Indebtedness  of an  Unrestricted Subsidiary or a foreign Subsidiary not
  constituting a Guarantor as to  which (a) neither the Company  nor any other
  Subsidiary (other  than  an  Unrestricted Subsidiary  or a  Subsidiary of
  such foreign  Subsidiary) (i) provides  credit  support   including  any
  undertaking,  agreement   or  instrument  which  would   constitute
  Indebtedness or (ii) is  directly or indirectly liable  for such Indebtedness
  and (b) no default  with respect to  such Indebtedness  (including any
  rights which  the holders thereof  may have  to take  enforcement action
  against an Unrestricted  Subsidiary or such foreign Subsidiary)  would permit
  (upon notice,  lapse of time  or both) any holder  of any other Indebtedness
  of the Company or  its other Subsidiaries to declare  a default on such other
  Indebtedness  or cause  the payment  thereof  to  be accelerated  or payable
  prior  to its  stated maturity.

            "Obligations" means, with respect to any Indebtedness,  any
  obligation thereunder, including, without limitation,  principal, premium
  and interest  (including  post petition  interest thereon),  penalties,
  fees, costs, expenses, indemnifications, reimbursements, damages and other
  liabilities.

            "Obligors" means the Company  and the  Guarantors, collectively;
  "Obligor" means the  Company or any Guarantor.

            "Officers' Certificate"  means a  certificate signed by the Chairman
  of the Board, a Vice  Chairman of the Board, the  President, the Chief
  Executive  Officer, the Chief Operating Officer  or a Vice President,  and by
  the  Chief Financial  Officer, the  Chief Accounting  Officer, the
  Treasurer, an  Assistant Treasurer,  the Secretary or an Assistant Secretary
  of the Company or a Subsidiary and  delivered to the Trustee, which shall
  comply with this Indenture.


                                       12
<PAGE>   20

            "Opinion of Counsel" means a written  opinion from legal  counsel
  who is  acceptable to the  Trustee.  The counsel may be an employee of or
  counsel to the Company, a Guarantor or the Trustee.

            "Order" means a  written order signed in the  name of the Company
  by an officer and delivered  to the Trustee.

            "Paying Agent" has the meaning specified in Section 2.03.

            "Permitted Holders" means Norex Industries,  Inc., Somerset Capital
  Partners, Mike L. Mullen and Roy T. Oliver and their respective Affiliates.

            "Permitted Indebtedness" means (a) Indebtedness of the Company under
  the Securities; (b) Indebtedness (and any  guarantee thereof) under one or
  more credit  or revolving credit facilities with a bank or syndicate of banks
  or financial institutions or  other lenders, including, without limitation,
  the Bank Credit Facility, as such may be amended, modified, revised,
  extended, replaced, or refunded from time  to time, in an aggregate principal
  amount at any  one time outstanding not to exceed  $100,000,000, less any
  amounts derived from  Asset Sales  and applied  to the  required permanent
  reduction  of  Senior Debt  (and a  permanent reduction  of the related
  commitment to  lend or amount available to  be reborrowed in the case of a
  revolving credit facility) under  such  credit facilities  as  contemplated
  by  the  provisions of  Section 4.07  of this  Indenture; (c) Indebtedness
  of  the  Company or  any  Subsidiary under  Interest  Swap Obligations,
  provided  that (i)  such Interest Swap  Obligations are related  to payment
  obligations on  Indebtedness otherwise permitted  under the provisions  of
  Section 4.03  of this Indenture  and (ii) the  notional principal amount of
  such Interest Swap Obligations does not exceed the  principal amount of the
  Indebtedness to  which such Interest Swap Obligations relate; (d)
  Indebtedness of the Company  or any Subsidiary under Currency  Hedge
  Obligations, provided that (i) such Currency Hedge Obligations  are related
  to payment obligations  on Indebtedness otherwise permitted under the
  provisions of Section 4.03 of this  Indenture or to the foreign currency cash
  flows reasonably expected  to be  generated by the  Company and  the
  Subsidiaries  and (ii)  the notional  principal amount of  such Currency
  Hedge Obligations  does not  exceed the principal  amount of  the
  Indebtedness and  the amount  of the  foreign currency cash flows to  which
  such Currency Hedge  Obligations relate; (e)  Indebtedness of the Company  or
  any Subsidiary outstanding  on the Issue Date  and listed on Schedule 1.01(a)
  attached hereto; (f) the  Guarantees of  the Securities (and any assumption
  of the Obligations guaranteed thereby);  (g) Indebtedness of the Company or
  any Subsidiary in  respect of bid  performance bonds,  surety bonds, appeal
  bonds  and letters of credit  or similar arrangements issued  for the
  account of the Company  or any Subsidiary, in  each case in the  ordinary
  course of business and  other than for an obligation for money  borrowed; (h)
  Indebtedness of the Company to a Guarantor or other Wholly  Owned Subsidiary
  and Indebtedness  of a Guarantor or  other Wholly Owned Subsidiary to  the
  Company  or another  Guarantor or other  Wholly Owned  Subsidiary; provided
  that upon  any subsequent issuance or transfer of any  Capital Stock or any
  other  event which results in any  such Guarantor ceasing to be a Guarantor
  or such Wholly Owned Subsidiary ceasing  to be a Wholly Owned  Subsidiary, as
  the case may be, or any other  subsequent transfer of  any such  Indebtedness
  (except to  the Company  or a  Guarantor or  other Wholly Owned Subsidiary),
  such Indebtedness shall be deemed, in each case, to be incurred





                                       13
<PAGE>   21

  and  shall  be treated  as an  incurrence  for purposes  of Section 4.03  of
  this  Indenture at  the  time the Guarantor  in question ceased  to be a
  Guarantor  or the Wholly  Owned Subsidiary  in question ceased  to be a
  Wholly Owned Subsidiary; (i) Subordinated  Indebtedness of the Company to an
  Unrestricted Subsidiary for  money borrowed; (j)  Indebtedness of  the
  Company  in connection  with a  purchase of  the Securities  pursuant to  a
  Change of Control  Offer, provided that the aggregate  principal amount of
  such  Indebtedness does not  exceed 101% of the aggregate principal amount
  at Stated Maturity of the Securities purchased pursuant to such  Change of
  Control Offer; provided, further, that such  Indebtedness (A) has an Average
  Life equal  to or greater than the remaining Average  Life of the Securities
  and  (B) does not mature prior  to one year following the Stated Maturity of
  the  Securities; (k) Permitted  Refinancing Indebtedness;  (l) Permitted
  Subsidiary  Refinancing Indebtedness; and (m) additional Indebtedness in  an
  aggregate principal amount not in excess of $2,500,000  at any one time
  outstanding.  So  as to  avoid duplication  in determining the  amount of
  Permitted  Indebtedness under any  clause of this definition,  guarantees
  permitted to  be incurred pursuant to  this Indenture of,  or Obligations
  permitted to be  incurred pursuant to this  Indenture in respect of  letters
  of credit supporting, Indebtedness otherwise included in the determination of
  such amount shall not also be included.

            "Permitted  Investments"   means  (a) certificates  of  deposit,
  bankers  acceptances, time  deposits, Eurocurrency deposits  and similar
  types  of Investments routinely  offered by  a commercial bank  organized in
  the United States with  final maturities  of one  year or  less issued by
  commercial banks  organized in  the United  States having  capital  and
  surplus  in excess  of $300,000,000;  (b) commercial  paper issued  by any
  corporation, if such  commercial paper has credit  ratings of at least  "A-1"
  or  its equivalent by S&P  and at least  "P-I"  or its equivalent by Moody's;
  (c) U.S. Government Obligations with a maturity  of four years or less; (d)
  repurchase obligations for instruments  of the type  described in clause (c)
  with any bank  meeting the qualifications specified in  clause (a) above; (e)
  shares of money  market mutual or similar  funds having assets in excess of
  $100,000,000; (f)  payroll advances in the ordinary course of business; (g)
  other  advances and  loans to  officers and employees  of the  Company or
  any Subsidiary,  so long as  the aggregate principal amount of  such advances
  and loans  does not  exceed $500,000  at any  one time  outstanding; (h)
  Investments represented  by that portion  of the proceeds from  Asset Sales
  that  is not  required to be  Cash Proceeds by Section 4.07 of  this
  Indenture;  (i) Investments made  by the  Company in Guarantors  or in  its
  other  Wholly Owned Subsidiaries (or any Person  that will be a Wholly Owned
  Subsidiary as  a result of such Investment)  or by a Subsidiary in the
  Company or in one or more Guarantors  or other Wholly Owned Subsidiaries (or
  any  Person that  will be a Wholly Owned Subsidiary  as a result of such
  Investment); (j) Investments in stock, obligations or  securities received
  in  settlement of  debts  owing to  the  Company or  any  Subsidiary  as  a
  result  of bankruptcy  or insolvency proceedings or upon the foreclosure,
  perfection or  enforcement of any Lien in favor of the Company or any
  Subsidiary, in each case as to  debt owing to the Company or any Subsidiary
  that arose in  the ordinary  course of  business of  the  Company  or any
  such Subsidiary;  (k) certificates  of deposit, bankers acceptances, time
  deposits, Eurocurrency deposits and similar  types of Investments routinely
  offered by  a commercial bank  organized in  the United  States with  final
  maturities of  one year  or less and  in an aggregate amount not to exceed
  $5,000,000 at  any one time outstanding with a  commercial bank organized in
  the United States having capital and surplus





                                       14
<PAGE>   22

  in  excess  of  $75,000,000;  (l)  Venezuelan   and  other  foreign  bank
  deposits  and  cash  equivalents  in jurisdictions  where the Company or its
  Subsidiaries are then actively  conducting business; (m) Investments in Grey
  Wolf  pursuant to the Grey Wolf Acquisition  agreement; (n) Interest Swap
  Obligations with respect to any floating rate Indebtedness that  is permitted
  by the  terms of this Indenture  to be outstanding; (o) Currency Hedge
  Obligations,  provided that such  Currency Hedge Obligations constitute
  Permitted Indebtedness permitted by  clause (d) of the definition thereof;
  (p) Investments in prepaid  expenses, negotiable instruments held for
  collection and  lease, utility,  worker's  compensation and  performance  and
  other  similar  deposits in  the ordinary course of  business; and (q)
  Investments pursuant to  any agreement or obligation  of the Company  or any
  Subsidiary in effect on the Issue Date and listed on a Schedule 1.01(b)
  attached hereto.

            "Permitted Liens" means (a) Liens in  existence on the Issue Date;
  (b) Liens created for the  benefit of the  Securities and/or the Guarantees;
  (c)  Liens on Property of a Person existing at  the time such Person is
  merged or  consolidated with or into the  Company or a Subsidiary  (and not
  incurred as a result of,  or in anticipation of, such transaction), provided
  that  any such Lien relates solely to such Property; (d) Liens  on Property
  existing at the time of the  acquisition thereof (and not incurred as a
  result of, or in anticipation of such  transaction), provided  that any such
  Lien relates  solely to such  Property; (e)  Liens incurred  or pledges and
  deposits made in connection  with worker's compensation, unemployment
  insurance  and other social security  benefits, statutory obligations, bid,
  surety  or appeal bonds, performance bonds or other obligations of a  like
  nature incurred  in the  ordinary course  of business;  (f) Liens  imposed by
  law  or arising  by operation   of  law,   including  without   limitation,
  landlords',  mechanics',   carriers',  warehousemen's, materialmen's,
  suppliers'  and  vendors Liens  and  Liens for  master's  and  crew's  wages
  and  other  similar maritime Liens, and  incurred in the ordinary course of
  business for sums not delinquent or being contested in good faith, if such
  reserves  or other appropriate provisions, if any, as shall be required by
  GAAP shall have been  made  with respect  thereof;  (g)  zoning restrictions,
  easements,  licenses,  covenants,  reservations, restrictions  on the  use
  of real  property and  defects, irregularities  and deficiencies  in title
  to real property that do not, individually or in  the aggregate, materially
  affect the  ability of the Company or  any Subsidiary to  conduct  its
  business  presently  conducted;  (h)  Liens for  taxes  or  assessments  or
  other governmental  charges or levies not  yet due and payable, or the
  validity of which is  being contested by the Company  or  a  Subsidiary in
  good  faith  and  by  appropriate  proceedings upon  stay  of  execution or
  the enforcement  thereof and for  which adequate  reserves in accordance
  with GAAP or  other appropriate provision has been made;  (i) Liens to
  secure Indebtedness incurred for  the purpose of financing  all or a part  of
  the purchase price or construction  cost of Property acquired  or constructed
  after the  Issue Date, provided that (l) the principal amount  of
  Indebtedness secured by such Liens shall  not exceed 100% of the lesser of
  cost or Fair  Market  Value of  the  Property  so  acquired, upgraded  or
  constructed plus  transaction  costs related thereto, (2)  such Liens  shall
  not  encumber any other  assets or Property  of the  Company or any
  Subsidiary (other than the proceeds  thereof and accessions and upgrades
  thereto) and (3) such Liens shall  attach to such Property within  120 days
  of the date  of the completion of the construction or  acquisition of such
  Property; (j)  Liens  securing Capital  Lease  Obligations,  provided,
  further,  that  such Liens  secure Capital  Lease Obligations which, when
  combined with (l) the outstanding secured Indebtedness of the Company and its





                                       15
<PAGE>   23

  Subsidiaries (other than  Indebtedness secured by Liens  described under
  clauses  (b) and (i)  hereof) and (2) the aggregate  principal amount of all
  other Capital Lease  Obligations of the Company  and Subsidiaries, does not
  exceed  $5,000,000 at any one time outstanding; (k) Liens to secure any
  extension, renewal, refinancing or refunding  (or successive  extensions,
  renewals,  refinancings or  refundings), in  whole or  in part,  of any
  Indebtedness secured  by Liens referred to in the  foregoing clauses (a), (c)
  and (d), provided, further, that such Lien does not  extend to any other
  Property of the Company  or any Subsidiary and the principal amount  of the
  Indebtedness  secured by such Lien is not increased;  (l) any charter or
  lease; (m) leases or subleases of real property  to other  Persons; (n)
  Liens securing  Permitted Indebtedness  described in  clause (b) of  the
  definition thereof;  (o) judgment liens  not giving  rise to an  Event of
  Default so  long as  any appropriate legal proceedings which may  have been
  initiated for the review of  such judgment shall not have  been finally
  terminated or the period within which such proceeding  may be initiated shall
  not have expired;  (p) rights of off-set of banks and other Persons; and (q)
  liens in favor of the Company.

            "Permitted Refinancing  Indebtedness" means Indebtedness of the
  Company,  incurred in exchange for, or the  net  proceeds  of  which  are
  used  to  renew,  extend,  refinance,  refund  or  repurchase,  outstanding
  Indebtedness of the Company  which outstanding  Indebtedness was incurred in
  accordance with, or is  otherwise permitted by, the terms  of clauses (a) and
  (e)  of the definition of "Permitted Indebtedness," provided that (i) if the
  Indebtedness being renewed, extended, refinanced,  refunded or repurchased is
  pari passu with  or subordinated in  right of  payment (without  regard to
  its being  secured) to  the Securities,  then such  new Indebtedness is pari
  passu with or subordinated in right of payment  (without regard to its being
  secured)  to, as the  case may be, the Securities  at least to the same
  extent as the  Indebtedness being renewed, extended, refinanced, refunded  or
  repurchased,  (ii) such new  Indebtedness  is scheduled  to mature  later
  than  the Indebtedness being renewed, extended, refinanced,  refunded or
  repurchased, (iii) such new Indebtedness has  an Average  Life  at the  time
  such Indebtedness  is  incurred that  is  greater  than  the Average  Life
  of the Indebtedness being renewed, extended, refinanced,  refunded or
  repurchased, and (iv) such new Indebtedness  is in aggregate principal amount
  (or, if such  Indebtedness is issued at a  price less than the principal
  amount thereof, the aggregate amount of gross proceeds therefrom  is) not in
  excess of the  aggregate principal amount then outstanding of the
  Indebtedness  being renewed, extended, refinanced, refunded  or repurchased
  (or  if the Indebtedness  being renewed, extended, refinanced, refunded  or
  repurchased was issued at a price less than the principal amount  thereof,
  then  not in excess  of the  amount of liability  in respect  thereof
  determined  in accordance with  GAAP) plus  the amount  of reasonable  fees,
  expenses  and premium,  if any,  incurred by  the Company or such Subsidiary
  in connection therewith.

            "Permitted Subsidiary Refinancing Indebtedness" means
  Indebtedness of  any Subsidiary,  incurred in exchange  for, or  the net
  proceeds of  which  are  used to  renew, extend,  refinance, refund  or
  repurchase, outstanding  Indebtedness of such Subsidiary which  outstanding
  Indebtedness was incurred  in accordance with, or is otherwise permitted by,
  the terms of  clauses (e) and (f) of the definition  of  "Permitted
  Indebtedness," provided that  (i) if the Indebtedness  being renewed,
  extended, refinanced,  refunded or repurchased  is pari passu with or
  subordinated in right of payment (without regard to its being secured) to the
  Guarantee





                                       16
<PAGE>   24

  of such  Subsidiary,  then such  new Indebtedness  is  pari  passu with  or
  subordinated  in  right of  payment (without regard to its  being secured)
  to, as  the case may be,  the Guarantee of such  Subsidiary at least  to the
  same  extent as the  Indebtedness being renewed, extended,  refinanced
  refunded or  repurchased, (ii) such new Indebtedness  is scheduled  to mature
  later than  the Indebtedness  being renewed,  extended, refinanced, refunded
  or repurchased,  (iii) such new  Indebtedness has  an Average  Life at the
  time such Indebtedness  is incurred  that is  greater than  the Average  Life
  of  the Indebtedness  being  renewed,  extended, refinanced, refunded  or
  repurchased, and  (iv) such  new Indebtedness  is in  an aggregate  principal
  amount (or,  if such Indebtedness is  issued at  a price  less than  the
  principal  amount thereof,  the aggregate  amount of  gross proceeds
  therefrom is)  not in excess of  the aggregate principal amount then
  outstanding of  the Indebtedness being renewed, extended,  refinanced,
  refunded or repurchased (or  if the Indebtedness being renewed, extended,
  refinanced, refunded or repurchased  was issued at a price less  than the
  principal amount thereof, then not in excess of the  amount of liability in
  respect  thereof determined in accordance with  GAAP) plus the amount of
  reasonable fees, expenses  and premium,  if any,  incurred by  the Company
  or such  Subsidiary in  connection therewith.

            "Person" means   any   individual,  corporation,   partnership,
  joint  venture,   incorporated   or unincorporated  association, joint stock
  company, trust,  unincorporated organization  or government  or other agency
  or political subdivision thereof or other entity of any kind.

            "Preferred Stock" of  any Person means Capital Stock  of such Person
  of any class  or classes (however designated) that ranks prior, as  to the
  payment of dividends and/or as to the distribution of assets upon any
  voluntary or involuntary liquidation, dissolution or  winding up of such
  Person, to shares of Capital Stock  of at least one other class of such
  Person.

            "Proceeding" has the meaning specified in Section 12.11(a).

            "Process Agent" has the meaning specified in Section 12.11(a).

            "Property" means, with respect to any Person,  any interest of such
  Person in any kind of  property or asset, whether real,  personal or  mixed,
  or  tangible or  intangible, excluding  Capital Stock  in any  other Person.

            "Qualified Equity Offering"  means an offering of  Capital Stock
  (other than Redeemable  Stock) of the Company for  cash,  whether  pursuant
  to an  effective  registration statement  under  the Securities  Act  or
  pursuant to an available exemption from registration under the Securities
  Act.

            "Record Date" means, for  the interest payable  on any Interest
  Payment Date, the  date specified in Section 2.12.

            "Redeemable Stock"  means, with  respect to  any Person,  any
  equity  security that  by its  terms or otherwise is required to  be
  redeemed, or is redeemable at the option of the holder thereof,  at any time
  prior to  one year following  the Stated  Maturity of  the Securities  or is
  exchangeable into Indebtedness  of such Person or any of its subsidiaries.





                                       17
<PAGE>   25

            "Redemption Date" means, when  used with  respect to  any Security
  or part  thereof to  be redeemed hereunder, the date fixed for redemption of
  such Securities pursuant  to the terms of the Securities and  this Indenture.

            "Redemption Price" means,  when used  with respect  to any  Security
  or  part thereof  to be  redeemed hereunder, the price  fixed for redemption
  of such  Security pursuant to the terms  of the Securities and this
  Indenture, plus accrued and unpaid interest thereon, if any to the Redemption
  Date.

            "Registrar" has the meaning specified in Section 2.03.

            "Related Business" means the  land  drilling  business and
  activities  incidental  thereto and  any business related or ancillary
  thereto.

            "Replacement Asset" means a Property or  asset that, as determined
  by the Board of  Directors of the Company as evidenced by a Board Resolution,
  is used or is useful in a Related Business.

            "Responsible  Officer" means,  when used  with respect  to the
  Trustee, any  officer assigned to the Corporate Trust Office, including  any
  vice president,  assistant vice president,  assistant secretary or  any other
  officer of the Trustee to whom any corporate  trust matter is referred
  because  of his or her knowledge of and familiarity with the particular
  subject.

            "Restricted Investment" means any Investment in  any Person,
  including an  Unrestricted Subsidiary or the designation of a Subsidiary as
  an Unrestricted Subsidiary, other than a Permitted Investment.

            "Restricted Payment" means to (i) declare or pay any dividend on, or
  make any distribution in  respect of,  or purchase,  redeem, retire  or
  otherwise acquire for  value, any  Capital Stock  of the  Company or any
  Affiliate  of the  Company, or  warrants, rights  or  options  to acquire
  such Capital  Stock, other  than (x) dividends payable solely in the Capital
  Stock (other than Redeemable Stock) of the Company or such  Affiliate, as the
  case  may be, or  in warrants,  rights or  options to acquire  such Capital
  Stock  and (y) dividends  or distributions by a Subsidiary to the Company or
  to a Wholly Owned Subsidiary; (ii)  make any principal payment on, or
  redeem, repurchase, defease  (including an in-substance  or legal defeasance)
  or otherwise acquire  or retire for value  (including pursuant  to mandatory
  repurchase covenants), prior  to any  scheduled principal payment, scheduled
  sinking  fund  payment or  other  stated  maturity,  Indebtedness  of the
  Company  or  any Subsidiary which is subordinated (whether  pursuant to its
  terms or by operation  of law) in right of  payment to the Securities or the
  Guarantees, as applicable; or (iii) make any Restricted Investment in any
  Person.

            "Retired Indebtedness or Stock" has the meaning specified in 
  Section 4.04.

            "S&P" means Standard & Poor's Ratings Group, a division of
  McGraw-Hill, Inc., or if Standard & Poor 's Ratings Group shall cease rating
  the specified debt securities and such ratings ceases with respect thereto
  shall have been transferred to a successor Person, such





                                       18
<PAGE>   26

  successor  Person, provided  that  if  Standard &  Poor's  Ratings  Group
  ceases rating  the  specified  debt securities  and its ratings  business
  with respect thereto  shall not have  been transferred  to any successor
  Person or  such successor Person  is Moody's,  then "S&P" shall mean any
  other  nationally recognized  rating agency selected in good faith by the
  Board of Directors of the Company in a Board Resolution.

            "Sale  and  Lease-Back Transaction" means,  with  respect  to  any
  Person, any  direct  or  indirect arrangement pursuant to  which Property is
  sold or  transferred by such Person or a subsidiary  of such Person and  is
  thereafter  leased  back from  the  purchaser  or  transferee thereof  by
  such Person  or  one of  its subsidiaries.

            "Security" has the  meaning stated  in the first  paragraph of
  this Indenture  and more particularly means any Security authenticated and
  delivered under this Indenture.

            "Security Register" has the meaning specified in Section 2.03.

            "Securities Act" means the Securities Act of 1933, as amended.

            "Senior Debt" means any Indebtedness incurred  by the Company,
  unless the instrument under  which such Indebtedness is incurred  expressly
  provides that it is  subordinated in right of  payment to the  Securities,
  provided that Senior Debt will not include (a) any liability for federal,
  state, local or other taxes owed or owing, (b) any  Indebtedness owing  to any
  Subsidiaries of the Company,  (c) any  trade payables  or (d)  any
  Indebtedness that is incurred in violation of this Indenture.

            "Significant Subsidiary" means  a Subsidiary that is a "significant
  subsidiary" as defined in Rule 1-02(w) of Regulation S-X under the
  Securities Act and the Exchange Act.

            "Special Record Date" means a date  fixed by the Trustee pursuant
  to Section 2.12 for the payment  of Defaulted Interest.

            "Stated Maturity" when used with  respect to a Security or any
  installment of  interest thereon, means the  date specified  in such
  Security as  the fixed  date on  which the  principal of  such Security  or
  such installment of interest is due and payable.

            "Subordinated Indebtedness" means  any  Indebtedness  of  the
  Company  or  any  Guarantor  that  is subordinated in right of payment to 
  the Securities or the Guarantees, as the case may be, and does not mature
  prior to one year following the Stated Maturity of the Securities.

            "subsidiary" means, with respect to any Person, (i)  any corporation
  more than 50% of the  outstanding Voting Stock  of which is owned, directly
  or indirectly,  by such Person, or by one or more other subsidiaries or  such
  Person,  or by  such Person  and one  or more  other subsidiaries  of such
  Person, (ii)  any general partnership, joint  venture  or similar  entity,
  more than  50%  of  the  outstanding partnership  or  similar interest of
  which is owned, directly or  indirectly, by such Person, or  by one or more
  other  subsidiaries of such Person, or by such





                                       19
<PAGE>   27

  Person and one  or more  other subsidiaries of  such Person  and (iii)  any
  limited  partnership of which  such Person or any subsidiary of such Person
  is a general partner.

            "Subsidiary"  means a  subsidiary of the Company  other than an
  Unrestricted Subsidiary;  provided that Indrillers shall not be considered a
  Subsidiary for purposes of this Indenture.

            "Surviving Entity"  has the meaning specified in Section 5.01.

            "Transaction Date" has the meaning specified within the definition
  of  "Consolidated Interest Coverage Ratio."

            "Trust Indenture  Act" or  "TIA"   means the Trust Indenture Act of
  1939, as amended, as in force at the date as of which this Indenture was
  executed.

            "Trustee"  means  the Person named as  the "Trustee"  in the  first
  paragraph of this  Indenture until a successor Trustee  shall  have  become
  such  pursuant  to  the  applicable  provision of  this  Indenture,  and
  thereafter  Trustee  shall mean such successor Trustee.

            "U.S. Government  Obligations" means securities that are  (i) direct
  obligations of  the United States of America  for the  payment of  which its
  full faith  and credit is pledged;  (ii) obligations  of a  Person controlled
  or supervised  by and acting as  an agency or instrumentality  of the United
  States  of America the payment  of which is unconditionally guaranteed as a
  full faith and credit obligation by the United States of America, which, in
  either  case under clauses (i) or (ii) above,  are not callable or redeemable
  at the option of  the issuers thereof;  or (iii)  depository receipts  issued
  by  a bank or  trust company as  custodian with respect to any such U.S.
  Government Obligations or a specific payment  of interest on or principal of
  any such U.S. Government  Obligation held  by such custodian  for the
  account of the  holder of  a Depository  receipt, provided that  (except as
  required  by law) such  custodian is not authorized to  make any deduction
  from the amount  payable to the holder of such Depository receipt from any
  amount received by the custodian in respect of the U.S. Government Obligation
  evidenced by such Depository receipt.

            "Uniform Commercial Code" means the New York Uniform Commercial Code
  as in effect from time to time.

            "Unrestricted Subsidiary" means any subsidiary  of the Company that
  the Company has classified as  an Unrestricted Subsidiary  and that  has not
  been  reclassified as  a Subsidiary pursuant  to the  terms of  this
  Indenture.

            "Voting Stock" means with  respect to any Person, securities of any
  class  or classes of Capital Stock in  such Person entitling the holder
  thereof (whether at  all times or at the times that  such class of Capital
  Stock has  voting power by reason of the happening of  any contingency) to
  vote in the  election of members of the board of directors or comparable body
  of such Person.





                                       20
<PAGE>   28

            "Wholly Owned Subsidiary" means any Subsidiary to the extent (i)
  all of the Capital  Stock or other ownership interests in such  Subsidiary,
  other than  any directors' qualifying shares mandated by  applicable law,
  is  owned  directly or  indirectly by  the Company  or (ii)  such  Subsidiary
  is  organized in  a foreign jurisdiction and  is required  by the  applicable
  laws  and  regulations of  such foreign jurisdiction to  be partially owned
  by  the government of such foreign  jurisdiction or individual or  corporate
  citizens of  such foreign jurisdiction in  order for such Subsidiary to
  transact business in such  foreign jurisdiction, provided that  the Company,
  directly or  indirectly, owns  the remaining Capital  Stock or  ownership
  interest  in such Subsidiary and, by contract or otherwise,  controls the
  management and business  of such Subsidiary and derives the economic
  benefits of ownership of such Subsidiary  to substantially the same  extent
  as if such Subsidiary were a wholly owned Subsidiary.

                   SECTION  1.02.  Incorporation by Reference of Trust
  Indenture Act.   This Indenture is subject to  the mandatory  provisions of
  the TIA  which are  incorporated by  reference in  and made  a part  of this
  Indenture.  The following TIA terms have the following meanings:

                    "indenture securities" means the Securities.

                    "indenture security holder" means a Holder.

                    "indenture to be qualified" means this Indenture.

                    "indenture trustee" or "institutional trustee" means the 
  Trustee.

                    "obligor" on the indenture securities means the  Company
  and  any other  obligor on  the indenture securities.

                   All other TIA terms  used in  this Indenture  that are
  defined by  the TIA,  defined by  TIA reference  to another  statute  or
  defined by  Commission rule  have  the meanings  assigned to  them  by such
  definitions.

                   SECTION 1.03.  Rules of Construction.  Unless the context
  otherwise requires:

                   (1)      a term has the meaning assigned to it;

                   (2)      an  accounting  term  not  otherwise  defined  has
           the  meaning  assigned  to it  in accordance with GAAP;

                   (3)      "or" is not exclusive;

                   (4)      "including" means including without limitation;

                   (5)      words  in the  singular  include the  plural  and
           words  in  the  plural include  the singular;





                                       21
<PAGE>   29

                   (6)      the words  "herein",  "hereof" and "hereunder" and
           other words of similar  import refer to this Indenture as a whole
           and not to any particular Article, Section or other subdivision;

                   (7)      provisions apply to successive events and
           transactions;

                   (8)      references  to agreements  and other  instruments
           include subsequent  amendments and waivers but only to the extent
           not prohibited by this Indenture; and

                   (9)      unless otherwise expressly  provided herein,  the
           principal amount  of any  Preferred Stock shall be  the greater of
           (i) the  maximum liquidation value of such Preferred  Stock or (ii)
           the maximum mandatory redemption or mandatory repurchase price with
           respect to such Preferred Stock.

                                   ARTICLE 2

                                 The Securities

                   SECTION 2.01.  Form and Dating.

           (a)     The  Securities,  with the  notation  of the  Guarantees
  endorsed  thereon and  the Trustee's certificate of  authentication thereon,
  shall be  substantially in  the forms of Exhibit A  and Exhibit B, each of
  which is hereby incorporated  in and expressly made a part of this Indenture.
  The Securities  may have such notations,  legends or endorsements  stamped,
  printed,  lithographed or engraved thereon  as required  by law, stock
  exchange  rule, agreements to  which the Company  is subject, if  any, or
  usage  (provided that any such notation, legend or  endorsement is in a  form
  acceptable to the  Company).  Each Security  shall be dated the date of its
  authentication.  The terms  of the Securities set forth in Exhibit A and
  Exhibit B are part of  the terms of this Indenture.

           (b)     The Securities shall  be issued initially in  the form of
  one or more permanent  global notes in definitive, fully  registered form,
  without coupons,  substantially in  the form  set forth  in Exhibit  A hereto
  (each a "Global Security"), each  such Security containing the legend
  relating to Global Securities set forth on the  face of the Security as set
  forth  on Exhibit A hereto.  Upon issuance, each such Global Security shall
  be duly executed by the  Company, with the endorsement of Guarantees therein
  executed by the  Guarantors, and authenticated  by the Trustee as hereinafter
  provided  and deposited with the  Trustee as custodian for the Depositary.
  Any Certificated  Security that may be  issued pursuant to Section 2.06(a)
  shall be issued  in the form of a note in definitive,  fully registered form,
  without coupons, substantially in  the form set forth in Exhibit B hereto
  (each a "Certificated  Security").  Upon  issuance, any such  Certificated
  Security shall  be duly executed  by the Company,  with the  endorsement of
  Guarantees thereon  executed by  the Guarantors,  and authenticated by the
  Trustee as hereinafter provided.





                                       22
<PAGE>   30

                   SECTION  2.02.   Execution and  Authentication.   The
  aggregate  principal  amount at  Stated Maturity of  Securities  outstanding
  at  any  time  shall  not  exceed  $175,000,000  except  as  provided  in
  Section 2.08  hereof.  Two  executive officers  of the  Company shall  sign
  the  Securities for the  Company by manual or facsimile  signature.  The
  Company's  seal shall be  impressed, affixed, imprinted  or reproduced on the
  Securities  and  may be  in facsimile  form.   The  Securities shall  have
  the notation relating  to  the Guarantees  executed  by each  Guarantor  in
  the manner  provided for  in  Section 11.03 hereof  and endorsed thereon.

                   If an executive officer of the Company whose  signature is
  on a Security no  longer holds that office at the time the Trustee
  authenticates the Security, the Security shall be valid nevertheless.

                   Notwithstanding any other provision hereof,  the Trustee
  shall authenticate  and deliver Notes only upon receipt by  the Trustee of an
  Officers' Certificate complying with  Sections 12.01 and 12.02 hereof an
  Opinion of Counsel with respect  to satisfaction of all conditions precedent
  contained in this Indenture  to authentication and delivery of such
  Securities.

                   Upon compliance  by the Company  with the provisions  of the
  previous  paragraph, the Trustee shall, upon receipt  of an Order requesting
  such action, authenticate Securities for original issuance  in an aggregate
  principal  amount at Stated Maturity not to  exceed $175,000,000 in the  form
  of the Global Security.  Such Order shall specify in the amount of Securities
  to be authenticated and  the date on which the Securities are  to be
  authenticated and  shall further provide  instructions concerning
  registration, amounts  for each Holder and delivery.

                   Upon  the occurrence of any  event specified in Section
  2.06(a) hereof  and compliance by the Company with the provisions  of the
  paragraph preceding the  immediately preceding paragraph, the Company shall
  execute and the Trustee shall authenticate  and deliver to each beneficial
  owner identified by the Depositary, in exchange  for such beneficial owner s
  interest in the Global Security, Certificated Securities representing
  Securities theretofore represented by the Global Security.

                   A  Security shall not  be valid until  an authorized
  signatory  of the  Trustee manually signs the certificate  of authentication
  on the Security.   The signature shall be  conclusive evidence, and the only
  evidence, that the Security has been authenticated under this Indenture.

                   The  Trustee may  appoint  an  authenticating agent
  reasonably acceptable  to the  Company to authenticate the Securities.
  Unless limited by the  terms of such appointment,  an authenticating agent
  may authenticate Securities whenever  the Trustee may do  so.  Each reference
  in this Indenture  to authentication by the Trustee includes  authentication
  by such agent.  An  authenticating agent has  the same rights  as any
  Registrar, Paying Agent or agent for service of notices and demands.

                   SECTION 2.03.  Registrar  and Paying Agent.   The Company
  shall maintain an office or agency where Securities may be presented for
  registration of transfer or for exchange





                                       23
<PAGE>   31

  (the "Registrar") and an office or agency where  Securities may be presented
  for payment  (the "Paying Agent").  The Registrar  shall keep a  register of
  the  Securities (the "Security Register") and of  their transfer  and
  exchange.   The Company may have one or  more co-registrars and one or more
  additional paying agents; provided, however, that so  long as Texas Commerce
  Bank National Association shall be  the Trustee, without the  consent of  the
  Trustee, there shall be no more  than one Registrar or  Paying Agent.  The
  term "Paying Agent" includes any additional paying agent.

                   The  Company shall  enter into  an appropriate  agency
  agreement  with any  Registrar,  Paying Agent or co-registrar not  a party
  to this Indenture,  which shall  incorporate the  terms of the  TIA.   The
  agreement shall  implement the  provisions of this  Indenture that  relate to
  such  agent.   The Company  shall notify the Trustee of the  name and address
  of any such  agent.  If the Company fails to maintain  a Registrar or Paying
  Agent, the Trustee  shall act as  such and shall  be entitled to  appropriate
  compensation  therefor pursuant to Section 7.07.

                   The Company initially appoints the  Trustee as Registrar and
  Paying  Agent in connection with the Securities.  The  Company may, upon
  written notice  to the Trustee, change the  designation of the Trustee as
  Registrar or  Paying Agent and appoint  another Person to act  as Registrar
  for  purposes of  this Indenture except that,  for the purposes  of Article
  3,  Article 8, Article 9  and Sections 4.07  and 4.09,  none of  the Company,
  any Guarantor, any  Restricted Subsidiary or any  Affiliate of the  Company
  or of any  Guarantor shall act  as Paying Agent.   If  any Person  other than
  the  Trustee acts as  Registrar, the Trustee  shall have the right at  any
  time,  upon reasonable  notice, to inspect  or examine  the Security
  Register and to make  such inquiries of the  Registrar as the Trustee  shall
  in its discretion deem  necessary or desirable in  performing its duties
  hereunder.

                   Upon surrender for  registration of transfer of  any
  Security at  an office or  agency of the Company designated  for such
  purpose,  the Company  shall  execute,  and the  Trustee shall  authenticate
  and deliver, in  the  name  of the  designated  transferee  or  transferees,
  one  or  more  new Securities  of  any authorized denomination  or
  denominations,  of like tenor and  aggregate principal amount, all  as
  requested by the transferor.

                   Every  Security presented or surrendered for  registration
  of transfer or  for exchange shall (if so  required by the Company, the
  Trustee or the Registrar) be duly endorsed, or  be accompanied by a duly
  executed  instrument of transfer in  form satisfactory to  the Company,  the
  Trustee and the  Registrar, by the Holder thereof or such Holder's attorney
  duly authorized in writing.

                   SECTION  2.04.   Paying  Agent  To  Hold  Money in  Trust.
  Prior  to  each due  date  of the principal, premium, if any, and  interest
  on any Security, the  Company shall deposit with the  Paying Agent a sum
  sufficient to pay such principal, premium, if any, and  interest when so
  becoming due.  The  Company shall require  each Paying Agent (other  than the
  Trustee) to agree in  writing that the Paying  Agent shall hold in trust for
  the benefit  of Holders  or the  Trustee all  money held  by the  Paying
  Agent  for  the payment  of principal, premium,  if any, of or interest  on
  the Securities and shall notify the Trustee  of any default by the Company in
  making any such





                                       24
<PAGE>   32

  payment.   If the Company or  a Subsidiary acts  as Paying Agent, it  shall
  segregate the money held  by it as Paying Agent and hold  it as a separate
  trust fund.  The Company at any time may require  a Paying Agent to pay all
  money  held by  it to  the Trustee  and to  account for  any funds  disbursed
  by the Paying  Agent.   Upon complying with  this Section, the Paying Agent
  shall have  no further liability for the money delivered to the Trustee.

                   SECTION 2.05  Global Securities.

           (a)     So long as  a Global Security  is registered  in the  name
  of the  Depositary or its  nominee, beneficial owners,  members of,  or
  participants in, the  Depositary ("Agent  Members") shall  have no  rights
  under this Indenture with respect to the Global Note held on their  behalf by
  the Depositary or the Trustee  as its  custodian, and the Depositary may be
  treated by the Company, the Guarantors, the Trustee and any agent of the
  Company or the Trustee as the absolute  owner of such Global Security  for
  all purposes.  Notwithstanding the foregoing, nothing herein  shall (i)
  prevent the Company, the Guarantors,  the Trustee or any agent of the Company
  or the Trustee  from  giving  effect to  any  written  certification, proxy
  or other  authorization furnished by the Depositary or (ii) impair,  as
  between the Depositary and its Agent Members, the operation  of customary
  practices governing the exercise of the rights of a Holder of Securities.

           (b)     The Holder  of  a Global  Security may  grant proxies  and
  otherwise authorize  any  Person, including Agent Members and Persons  that
  may hold interests in such  Global Securities through Agent Members, to take
  any action which a Holder of Notes is entitled to take under this Indenture
  or the Notes.

           (c)     Whenever, as a  result of an optional  redemption of
  Securities  by the Company,  a Change of Control Offer, an Asset Sale Offer,
  or an exchange pursuant to the second sentence of Section 2.06(a)  hereof, a
  Global Security is redeemed, repurchased or exchanged  in part, such Global
  Security shall  be surrendered by the Holder thereof to the Trustee who
  shall cause an adjustment to  be made to a Schedule A  attached thereto so
  that the principal amount  at Stated Maturity of such Global Security will
  be equal to the portion of such Global  Security not redeemed,  repurchased
  or exchanged  and shall thereafter  return such  Global Security to such
  Holder, provided  that each such  Global Security shall be in  a principal
  amount  at Stated Maturity  of $1,000 or an integral multiple thereof.

           SECTION 2.06  Transfer and Exchange.

           (a)     Any  Global  Security shall  be  exchanged  by  the Company
  for  one  or  more  Certificated Securities, if (x) the Depositary (i) has
  notified the Company  that it is unwilling or unable  to continue as, or
  ceases to be,  a "Clearing Agency" registered under Section 17A of the
  Exchange Act and  (ii) a successor to the  Depositary registered as  a
  "Clearing Agency" under Section 17A  of the  Exchange Act  is not  able to be
  appointed by the  Company within 90 days or (y) the Depositary is at any time
  unwilling or unable to continue as Depositary and  a successor to the
  Depositary is not  able to be appointed  by the Company within  90 days.  If
  an Event of Default  occurs and is  continuing, the Company  shall, at the
  request of  the Holder thereof, exchange all or part of any Global Security,
  for one or more Certificated Securities, as the case





                                       25
<PAGE>   33

  may be; provided  that the principal  amount at  Stated Maturity  of each
  such  Certificated Security shall  be $1,000 or an integral multiple thereof.
  Whenever a Global Security  is exchanged as a whole for one or  more
  Certificated  Securities, it  shall be  surrendered by  the Holder  thereof
  to  the Trustee  for  cancellation.  Whenever  a Global  Security  is
  exchanged in  part  for one  or  more  Certificated Securities  it  shall  be
  surrendered  by the Holder  thereof to  the Trustee  and the  Trustee shall
  make the appropriate  notations to Schedule A thereof pursuant to Section
  2.05(c)  hereof.  All Certificated Securities issued in exchange for  a
  Global  Security or any portion  thereof shall be  registered in  such names,
  and delivered,  as the Depositary shall instruct the Trustee.

           (b)     A Holder  may transfer a Security  only upon the surrender
  of such Security for  registration of  transfer.  No such transfer  shall be
  effected until, and the transferee shall  succeed to the rights of a Holder
  only  upon, final  acceptance  and  registration of  the  transfer  in  the
  Security  Register by  the Registrar.  When  Securities are presented to the
  Registrar with a request to register  the transfer of, or to exchange, such
  Securities,  the Registrar shall register the  transfer or make such
  exchange as requested  if its requirements for  such transactions and  any
  applicable  requirements hereunder are  satisfied.  To  permit registrations
  of transfers  and  exchanges, the  Company shall  execute and  the  Trustee
  shall  authenticate Certificated Securities at the Registrar's request.

           (c)     The Company shall not  be required to make  and the
  Registrar need  not register transfers or exchanges  of  (a) Certificated
  Securities  selected  for  redemption  (except, in  the  case  of
  Certificated Securities to  be redeemed in part, the portion thereof not to
  be  redeemed), or (b) any Certificated Security for a  period of 15  days
  before  a selection  of Certificated Securities  to be redeemed  or the
  mailing  of a notice  of a  Change of  Control Offer  pursuant  to Section
  4.09  hereof or  an Asset  Sale Offer  pursuant to Section 4.07 hereof and
  ending on the close of business on the day of such mailing.

           (d)     No service charge  shall be made for any  registration of
  transfer  or exchange of Securities, but the Company may require  payment of
  a sum  sufficient to cover any  tax or other governmental  charge that may
  be imposed  in connection  with any  registration of  transfer of  Securities
  (other  than in  respect  of exchanges or transfers pursuant to Sections
  2.10, 3.06, 407, 4.09 and 10.06).

           (e)     All Securities  issued upon any  registration of transfer,
  exchange or substitution  pursuant to the terms of  this Indenture will
  evidence  the same debt and  will be entitled  to the same benefits  under
  this Indenture as the Securities surrendered for such registration of
  transfer, exchange or substitution.

           (f)     Any Holder of a  Global Security  shall, by acceptance  of
  such  Global Security, agree  that transfers of  beneficial interests in such
  Global Security may  be effected only through  a book entry  system
  maintained by the Holder of such  Global Security (or its agent), and that
  ownership of a beneficial interest in the Securities  represented hereby
  shall be required to  be reflected in book  entry form.  Transfers  of a
  Global Security shall be  limited to transfers in  whole and not  in part,
  to the Depositary, its  successors, and their respective nominees.  Interests
  of





                                       26
<PAGE>   34
  beneficial owners in a  Global Security may be transferred in accordance with
  the rules  and procedures of the Depositary (or its successors).

                   SECTION  2.07.   Holder  Lists.   The  Trustee shall
  preserve  in as  current  a form  as  is reasonably  practicable the most
  recent  list available to it  of the names and addresses of  Holders.  If the
  Trustee  is not the  Registrar, the Company shall furnish  to the Trustee,
  in writing at  least five Business Days before  each Interest Payment Date
  and at such  other times as the  Trustee may request in writing, a list in
  such form and as of such date as the Trustee may reasonably require of the
  names and addresses of Holders.

                   SECTION 2.08.   Replacement  Securities.   If  a mutilated
  Security  is surrendered  to  the Registrar or  if the  Holder of  a Security
  claims that the  Security has been  lost, destroyed  or wrongfully taken, the
  Company shall issue and  the Trustee shall authenticate a replacement
  Security if the  requirements of Section  8-405  of the  Uniform Commercial
  Code  are  met and  the Holder  satisfies  any other  reasonable requirements
  of  the Trustee.   If  required by  the  Trustee  or the  Company, such
  Holder shall  furnish an indemnity  bond  sufficient in  the  judgment of
  the  Company  and the  Trustee  to protect  the  Company, the Guarantors,
  the Trustee, the Paying Agent, the  Registrar and any co-registrar from any
  loss which any of them may suffer  if a Security  is replaced.  In  case any
  such  mutilated, destroyed, lost  or stolen Security has become  or is about
  to  become due and  payable, the Company, in  its discretion may, instead  of
  issuing a new Security, pay such Security.

                   Upon the  issuance of  any new Security under  this Section
  2.08, the Company  may require the payment by  the Holder of a sum sufficient
  to cover  any tax or other governmental charge  that may be imposed in
  relation  thereto  and any  other expenses  (including the  fees  and
  expenses  of the  Trustee)  connected therewith.

                   Every new  Security issued pursuant  to this Section 2.08 in
  lieu  of any destroyed,  lost or stolen Security shall  constitute an
  original additional contractual obligation of the Company,  whether or not
  the destroyed, lost or stolen Security shall  be at any time enforceable  by
  anyone, and shall be  entitled to all the  benefits of this Indenture equally
  and  proportionately with any and  all other Securities duly issued
  hereunder.

                   The provisions of this  Section 2.08 are exclusive and shall
  preclude (to the  extent lawful) all other rights  and remedies with  respect
  to  the replacement  or payment of  mutilated, destroyed, lost  or stolen
  Securities.

                   SECTION  2.09.    Outstanding  Securities.    Securities
  outstanding  at  any  time  are  all Securities authenticated  by  the
  Trustee  except  for  those  canceled  by it,  those  delivered  to  it  for
  cancellation  and those  described in  this Section  as  not outstanding.   A
  Security does  not  cease  to be outstanding because the Company or an
  Affiliate of the Company holds the Security.

                   If a  Security is replaced pursuant to Section 2.08,  it
  ceases to be  outstanding unless the Trustee and the Company receive proof
  satisfactory  to them that the replaced Security is held by a bona  fide
  purchaser, in which event the replacement Security shall cease to be





                                       27
<PAGE>   35

  outstanding, subject to the provisions  of Section 8-405 of the Uniform
  Commercial Code. A mutilated Security ceases to be outstanding upon surrender
  of such Security and replacement thereof pursuant to Section 2.08.

                   If the Paying Agent  (other than the Company, a Guarantor or
  an Affiliate of the  Company or a Guarantor) segregates and holds in trust,
  in accordance  with this Indenture, on a Redemption  Date or Maturity date
  money sufficient  to pay all principal, premium, if any,  interest and any
  other amounts  payable on that date with respect  to the Securities (or
  portions thereof) to  be redeemed or  maturing, as the case may  be, then on
  and after  that date such  Securities (or such  portions thereof)  shall
  cease to  be outstanding  and interest on them shall cease to accrue.

                   In  determining whether  the Holders  of  the required
  principal  amount of  Securities have concurred in  any  direction,  waiver
  or  consent  or any  amendment,  modification or  other change  to  this
  Indenture, Securities held or  beneficially owned by the  Company or
  Guarantor  or an Affiliate of  the Company or  a Guarantor of the Company or
  by agents  of any of the foregoing shall be disregarded, except that for the
  purposes  of determining whether the  Trustee shall be  protected in  relying
  on any such  direction, waiver or consent or  any  amendments,  modification
  or  other  change  to  this  Indenture,  only  Securities  which  a
  Responsible  Officer knows are so owned shall be  so disregarded.  Securities
  so owned which have been pledged in  good faith shall  not be disregarded  if
  the pledgee establishes to  the satisfaction of  the Trustee such pledgee s
  right so  to act with respect to the Securities and that the pledgee is  not
  the Company, a Guarantor or an Affiliate of the Company or of a Guarantor or
  any of their agents.

                   SECTION 2.10.   Temporary  Securities.   Until definitive
  Securities are ready  for delivery, the Company may prepare and  the Trustee
  shall authenticate temporary  Securities.  Temporary  Securities shall be
  substantially  in the form  of definitive  Securities but  may have
  variations that  the Company  considers appropriate for temporary Securities.
  Without unreasonable  delay, the Company shall prepare and  the Trustee shall
  authenticate definitive Securities and deliver them in exchange for temporary
  Securities.

                   SECTION 2.11.  Cancellation.   The Company at any time may
  deliver Securities to the Trustee for cancellation.  The Registrar and the
  Paying  Agent shall forward to the Trustee  any Securities surrendered to
  them for  registration of transfer,  exchange or payment.   The Trustee and
  no one  else shall cancel  and destroy (subject  to the  record retention
  requirements  of the  Exchange Act) all  Securities surrendered for
  registration of transfer, exchange,  payment or cancellation  and deliver a
  certificate of such  destruction to the  Company.   The  Company may  not
  issue  new Securities  to  replace Securities  it has  redeemed, paid  or
  delivered to the Trustee for cancellation.

           SECTION 2.12   Payment of  Interest:  Interest  Rights Preserved.
  Interest  on any Security  which is payable, and  is punctually paid or  duly
  provided for,  on any  Interest Payment Date,  shall be paid  to the Person
  in whose  name such  Security is  registered at  the close  of business  on
  the  Record Date  for such interest payment,  which shall be  the June  15 or
  December 15 (whether or  not a  Business Day)  immediately preceding such
  Interest Payment Date.





                                       28
<PAGE>   36

                   Any interest on any  Security which is payable,  but is not
  punctually  paid or duly provided for, on any Interest Payment Date  (herein
  called  "Defaulted Interest") shall forthwith cease to be payable  to the
  registered Holder  on the  relevant  Record Date,  and, except  as
  hereinafter provided,  such  Defaulted Interest and any  interest payable on
  such Defaulted Interest may be paid by the  Company, at its election, as
  provided in clause (a) or (b) below:

           (a)     The  Company may elect to make  payment of any Defaulted
  Interest, and any interest payable on such Defaulted Interest, to the Persons
  in whose names the Securities are registered at the close of  business on a
  Special Record Date  for the payment of  such Defaulted Interest, which
  shall be fixed in  the following manner.  The Company shall notify the
  Trustee in writing of the  amount of Defaulted Interest proposed  to be paid
  on the Securities and the  date of the proposed payment, and at the  same
  time the Company shall deposit with the  Trustee an  amount of money  equal
  to the  aggregate amount proposed  to be paid  in respect of  such Defaulted
  Interest  or shall make arrangements satisfactory to  the Trustee for such
  deposit prior to the date of  the proposed  payment, such  money when
  deposited to  be held  in trust  for the  benefit of  the Persons entitled
  to such  Defaulted Interest  as provided  in  this  clause (a).   Thereupon
  the  Trustee shall  fix a Special  Record Date for the payment  of such
  Default Interest  which shall be  not more than 15  days and not less than 10
  days prior to the  date of the proposed payment  and not less than 10  days
  after the receipt  by the Trustee of the  notice of the  proposed payment.
  The  Trustee shall promptly  notify the Company  of such Special Record Date
  and, in the name  and at the expense  of the Company, shall  cause notice of
  the proposed payment of  such Defaulted Interest and the Special  Record Date
  therefor to be sent, first class mail, postage prepaid, to  each Holder at
  such Holder's address as it  appears in the  Security Register, not less
  than 10 days prior to  such Special Record Date.   Notice of the proposed
  payment  of such Defaulted Interest  and the Special  Record Date therefor
  having  been mailed as  aforesaid, such  Defaulted Interest shall be  paid to
  the Persons in whose  names the Securities are registered at the close of
  business on such Special Record Date and shall no longer be payable pursuant
  to the following clause (b).

           (b)     The Company  may make payment  of any  Defaulted Interest,
  and  any interest payable on  such Defaulted Interest, on  the Securities in
  any  other lawful manner  not inconsistent with  the requirements of any
  securities exchange  on which the Securities may  be listed, and  upon such
  notice as  may be required  by such  exchange, if, after notice given by the
  Company to the Trustee  of the proposed payment pursuant to this clause, such
  manner of payment shall be deemed practicable by the Trustee.

                   Subject  to the  foregoing provisions  of this  Section,
  each  Security delivered  under this Indenture  upon registration of transfer
  of, or in exchange  for, or in lieu  of, or in substitution for, any other
  Security, shall carry the rights  to interest accrued and unpaid, and to
  accrue, which were carried by such other Security.

                   SECTION 2.13   Authorized Denominations.   The Securities
  shall be issuable  in denominations of $1,000 and any integral multiple
  thereof.

                   SECTION 2.14.  CUSIP Numbers.   The Company in issuing the
  Securities may use "CUSIP" numbers (if then generally in use) and, if so, the
  Trustee shall use "CUSIP"





                                       29
<PAGE>   37

  numbers in notices  of redemption as  a convenience  to Holders;  provided,
  however, that  any such notice  may state  that  no representation  is  made
  as  to the  correctness  of such  numbers  either as  printed  on the
  Securities or as  contained in any notice  of a redemption  and that reliance
  may  be placed only on  the other identification numbers printed on the
  Securities,  and any such redemption shall not be affected by any  defect in
  or omission of such numbers.

                                   ARTICLE 3

                                   Redemption

                   SECTION 3.01.   Notices to Trustee.   If the Company elects
  to redeem Securities  pursuant to Section 3.07  and paragraph 5  of the
  Securities, it  shall notify  the Trustee  in writing of  the Redemption
  Date,  the principal  amount of  Securities  to be  redeemed, the  Redemption
  Price and  the Section  of  this Indenture and the paragraph of the
  Securities pursuant to which the redemption will occur.

                   The Company shall give  each notice to the  Trustee provided
  for  in this Section at  least 60 days before  the Redemption  Date unless
  the Trustee  consents to  a  shorter period.   Such  notice shall  be
  accompanied by an  Officers  Certificate and an Opinion  of Counsel from the
  Company to the effect  that such redemption will comply with the conditions
  herein and in the Securities.

           SECTION 3.02.   Selection of  Securities To Be Redeemed.   If less
  than all the Securities  are to be redeemed at any time, the  Trustee shall
  select the Securities to  be redeemed on a pro rata basis, or  by any other
  method which  the Trustee  shall  determine to  be fair  and  appropriate and
  which complies  with  any securities exchange and other  applicable
  requirements, provided that the  Trustee may select for redemption in part
  only Securities in denominations larger  than $1,000.  In selecting
  Securities to be redeemed pursuant  to this Section 3.02, the Trustee  shall
  make such adjustments,  reallocations and eliminations as  it shall  deem
  proper so that  the principal amount at Stated Maturity of  each Security to
  be  redeemed shall be $1,000 or an integral multiple  thereof, by increasing,
  decreasing  or eliminating  any amount less than  $1,000 which would be
  allocable to  any Holder.   If  the Notes  to be  redeemed are  Certificated
  Securities,  the  Certificated Securities to be  redeemed shall be selected
  by the Trustee by prorating, as nearly as may  be, or by any other method
  which  the Trustee shall determine  to be fair  and appropriate and which
  complies with any  securities exchange and other  applicable requirements,
  the  principal amount of  Certificated Securities to  be redeemed among the
  Holders of  Certificated Securities  registered in  their  respective names.
  The  Trustee in  its discretion may determine the particular Securities (if
  there are more  than one) registered in the name  of any Holder which are to
  be redeemed, in  whole or in part.  Provisions of  this Indenture that apply
  to Securities called for redemption also  apply to portions of  Securities
  called for  redemption.  The Trustee  shall notify the Company promptly of
  the Securities or portions of Securities to be redeemed.





                                       30
<PAGE>   38

                   SECTION 3.03.   Notice of Redemption.   At least 30 days but
  not  more than 60 days  before a date for redemption of Securities, the
  Company shall mail a  notice of redemption by first-class mail to  each
  Holder of Securities to be redeemed.

                   The notice shall identify the Securities to be redeemed and
shall state:

                   (1)      the Redemption Date;

                   (2)      the Redemption Price;

                   (3)      the name and address of the Paying Agent;

                   (4)      that  Securities called  for redemption must  be
           surrendered  to the  Paying Agent to collect the redemption price;

                   (5)      if  any Global  Security is  being redeemed  in
           part, the  portion of  the principal amount of such Security to be
           redeemed and that, after the Redemption Date, the Global Security,
           with a notation on Schedule A  thereof adjusting the principal
           amount thereof to be equal to the unredeemed portion, will be
           returned to the Holder thereof;

                   (6)      if any Certificated Security is being redeemed in
           part, the portion of the  principal amount  of  such Security  to be
           redeemed and  that, after  the Redemption  Date, a  new Certificated
           Security  or Certificated  Securities  in principal  amount equal
           to the  unredeemed portion  will be issued;

                   (7)      if fewer than all  the outstanding Securities are
           to be  redeemed, the identification and principal amounts of the
           particular Securities to be redeemed;

                   (8)      that, unless  the Company defaults  in making such
           redemption payment or  the Paying Agent  is prohibited from  making
           such payment  pursuant to the  terms of this  Indenture, interest on
           Securities (or  portion thereof) called for  redemption ceases to
           accrue on and after  the redemption date;

                   (9)      that  no  representation is  made as  to  the
           correctness  or accuracy  of  the CUSIP number, if any, listed in
           such notice or printed on the Securities;

                   (10)     the paragraph  of the Securities and  the Section
           of the Indenture  pursuant to which the Securities are being called
           for redemption; and

                   (11)     any other  information necessary  to  enable
           Holders  to comply  with the  notice  of redemption.

                   At the  Company's request, the Trustee  shall give  the
  notice of redemption  in the Company's name and at the Company's expense.  In
  such event, the Company shall provide the





                                       31
<PAGE>   39

  Trustee with  the information required by this Section at least 45 days
  before  the redemption date unless the Trustee consents to a shorter period.

                   SECTION 3.04.    Effect  of  Notice of  Redemption.   Once
  notice  of redemption  is  mailed, Securities  called for redemption become
  due and payable  on the  Redemption Date and at  the Redemption Price stated
  in the  notice.  Upon surrender  to the Paying Agent, such Securities shall
  be paid at  the Redemption Price stated  in the notice, plus accrued and
  unpaid  interest to the Redemption Date.  Failure to give notice or any
  defect in the notice to any Holder shall not affect the validity of the
  notice to any other Holder.

                   SECTION  3.05.  Deposit of Redemption  Price.  Prior to the
  Redemption Date, the Company shall deposit with the  Paying Agent (or, if the
  Company  or a Subsidiary is  the Paying Agent, shall  segregate and hold  in
  trust) money sufficient to pay the Redemption Price of and  accrued and
  unpaid interest on all Securities to  be redeemed on that date other than
  Securities or portions of  Securities called for redemption which have been
  delivered by the Company to the Trustee for cancellation.

                   So long as  the Company  complies with the  preceding
  paragraph and the  other provisions  of this Article 3,  interest on the
  Securities  to be redeemed on  the applicable Redemption  Date shall  cease
  to accrue from and after such  date and such Securities or portions thereof
  shall be deemed not to be entitled to any  benefit under this Indenture
  except to receive  payment of  the Redemption Price on  the Redemption Date.
  If any Security  called  for redemption  shall  not be  so  paid upon
  surrender for redemption,  then,  from Redemption Date  until such principal
  is paid, interest  shall be  paid on the  unpaid principal  and, to  the
  extent permitted by law,  on any  accrued but unpaid  interest thereon,  in
  each  case at  the rate prescribed therefor by  this Indenture and such
  Securities.

                   SECTION  3.06    Securities  Redeemed  in  Part.    Upon
  surrender  and  cancellation  of  a Certificated Security that  is redeemed
  in part, the  Company shall issue and  the Trustee shall  authenticate and
  deliver to  the  surrendering Holder  (at the  Company's expense)  a new
  Certificated Security  equal in principal amount to the  unredeemed portion
  of  the Certificated Security  surrendered and canceled,  provided that  each
  such  Certificated Security  shall be  in a  principal amount  at Stated
  Maturity of  $1,000 or  an integral multiple thereof.

                   Upon surrender of a Global Security  that is redeemed in
  part, the Paying Agent shall forward such Global Security to  the Trustee
  who shall make  a notation on Schedule A thereof  to reduce the principal
  amount of such Global Security to an amount equal  to the unredeemed portion
  of such Global Note, as provided in Section 2.05 hereof.

                   SECTION 3.07  Optional Redemption.

                   (a)      Except as  set forth in subsection (b) of this
  Section 3.07, the Company  shall not have the option to redeem the
  Securities pursuant to  this Section 3.07 prior to July 1, 2002.  On or
  after such date, the Company shall have the option to redeem the
  Securities, in whole or in part  upon not less than 30 days' nor more than
  60 days' notice, at the Redemption





                                       32
<PAGE>   40

  Prices  (expressed as percentages of principal  amount at Stated Maturity),
  if redeemed during the twelve month period beginning July  1 of the  years
  indicated  below, in each case,  together with any interest  accrued and
  unpaid to the Redemption Date:

               Year                                                  Percentage
               ----                                                  ----------
               2002 . . . . . . . . . . . . . . . . . . . . . . . .   104.4375% 
               2003 . . . . . . . . . . . . . . . . . . . . . . . .   102.9580% 
               2004 . . . . . . . . . . . . . . . . . . . . . . . .   101.4792% 
               2005 and thereafter  . . . . . . . . . . . . . . . .   100.0000%

                   (b)      Notwithstanding  the foregoing,  at any  time
  during  the first  36 months  after the Issue Date,  the Company may, at its
  option, redeem up to a maximum of 30%  of the aggregate principal amount at
  Stated Maturity of the  Securities with the net cash proceeds of one or more
  Qualified  Equity Offerings at a  Redemption Price  equal  to 108.875%  of
  the  principal amount  thereof, plus  accrued and  unpaid interest thereon to
  the Redemption  Date; provided  that at  least $120,000,000  aggregate
  principal  amount at  Stated Maturity of the  Securities shall remain
  outstanding immediately after  the occurrence of any such  redemption; and
  provided, further, that  each such redemption shall occur within 90 days of
  the  closing of such Qualified Equity Offering.

                                   ARTICLE 4

                                   Covenants

                   SECTION 4.01.   Payment  of Securities.   The  Company shall
  promptly pay  the principal  of, premium, if any, on  and interest on the
  Securities on the dates  and in the manner provided in the  Securities and in
  this Indenture.   Principal, premium  and interest shall be considered  paid
  on the date  due if on  or before  10:00 a.m.,  Houston time, on  such date
  the  Trustee or a  Paying Agent, other  than the Company  or a Guarantor, or
  an Affiliate  of the  Company or  a Guarantor,  holds in  accordance with
  this Indenture  money sufficient to pay  all principal, premium and  interest
  then due and the Trustee  or the Paying Agent,  as the case may be,  is not
  prohibited from paying  such money to the  Holders on that date pursuant to
  the  terms of this Indenture.

                   The Company  shall pay  interest on overdue  principal at
  the  rate specified therefor  in the Securities plus 1%  per annum, and it
  shall pay interest on overdue  installments of interest (without  regard to
  any applicable grace period) at the same rate to the extent lawful.

                   SECTION  4.02.  Commission  Reports.   So long as  any
  Securities are  outstanding, whether or not the Company is subject to Section
  13(a) or 15(d) of the Exchange Act, or any successor  provision thereto, the
  Company shall  file with the Commission the  annual reports, quarterly
  reports  and other documents  which the Company would  have been required to
  file  with the Commission pursuant to  such Section 13(a) or 15(d) or any
  successor provision thereto if the





                                       33
<PAGE>   41

  Company were subject  thereto, such documents to  be filed with  the
  Commission  on or prior to  the respective dates (the "Required Filing Dates")
  by which the Company would  have been required to file them.   The Company
  shall also  (whether or  not it  is required to file  reports with  the
  Commission),  within 30  days of  each Required Filing Date, (i) transmit  by
  mail to all Holders of  Securities, as their names and addresses appear in the
  Security Register, without  cost to such Holders or Persons, and (ii) file
  with the  Trustee, copies of the annual reports,  quarterly reports and other
  documents (without exhibits) which the Company has  filed or would have filed
  with the  Commission pursuant to Section  13(a) or 15(d) of  the Exchange Act,
  any  successor provisions thereto or  this Section 4.02.  The Company shall
  not be required  to file any report, document or other information with the
  Commission if the Commission does not permit such filing.

                   SECTION 4.03.  Limitation on Indebtedness.  The  Company
  will not, and will not  permit any of its Subsidiaries to, directly or
  indirectly, incur any  Indebtedness (including Acquired Indebtedness)
  unless, after giving  pro forma  effect to  the incurrence  of such
  Indebtedness, the  Consolidated Interest  Coverage Ratio for the
  Determination Period would  be at least  2.0 to 1.0 if such  Indebtedness is
  incurred  prior to July  1, 1998  and at least 2.25  to 1.0  if such
  Indebtedness is  incurred thereafter.   Notwithstanding the foregoing,  the
  Company  or any  Subsidiary may  incur Permitted Indebtedness.   Any
  Indebtedness of  a Person existing at the time at which  such Person becomes
  a Subsidiary  (whether by merger, consolidation, acquisition or otherwise)
  shall be deemed incurred by such Subsidiary at the time at which it becomes a
  Subsidiary.

                   SECTION 4.04.  Limitation  on Subsidiary Indebtedness and
  Preferred  Stock . The Company will not  permit any  Subsidiary to, directly
  or indirectly, incur  any Indebtedness or issue  any Preferred Stock except:

           (i)  Indebtedness or Preferred Stock issued to  and held by the
  Company, a Guarantor or a Wholly Owned Subsidiary, so  long as  any transfer
  of such  Indebtedness or  Preferred Stock  to  a Person  other than  the
  Company,  Guarantor  or  a  Wholly Owned  Subsidiary  will  be  deemed  to
  constitute  an  incurrence of  such Indebtedness or Preferred Stock by the
  issuer thereof as of the date of such transfer;

           (ii)   Acquired Indebtedness or  Preferred Stock of  a Subsidiary
  issued and  outstanding prior to the date on  which such Subsidiary was
  acquired by  the Company (other than  Indebtedness or Preferred Stock issued
  in connection with or in anticipation of such acquisition);

           (iii)   Indebtedness or  Preferred Stock  outstanding on the  Issue
  Date  and listed  on Schedule 4.04 attached hereto;

           (iv)  Indebtedness described in clauses (b), (c),  (d), (e), (f),
   (g) and (h) under the definition of "Permitted Indebtedness";

           (v)  Permitted Subsidiary Refinancing Indebtedness of such
Subsidiary;





                                       34
<PAGE>   42

           (vi)  Indebtedness or  Preferred Stock issued in  exchange for, or
  the proceeds  of which are used  to refinance, repurchase  or redeem,
  Indebtedness or Preferred Stock described  in clauses (i) and  (iii) of this
  Section  (the  "Retired  Indebtedness or  Stock"), provided  that the
  Indebtedness or  the Preferred  Stock  so issued  has (A) a principal  amount
  or liquidation value,  as the case may  be, not in excess  of the principal
  amount  or liquidation value  of the Retired Indebtedness  or Stock plus
  related expenses  for redemption and issuance, (B) a  final redemption date
  later than the stated maturity or final redemption date (if any) of the
  Retired Indebtedness  or  Stock  and (C)  an Average  Life at  the time  of
  issuance of  such Indebtedness  or Preferred Stock that is greater than the
  Average Life of the Retired Indebtedness or Stock;

           (vii)    Indebtedness  of  a  Subsidiary  which  represents  the
  assumption  by  such  Subsidiary  of Indebtedness  of  another Subsidiary  in
  connection with  a  merger of  such  Subsidiaries,  provided  that no
  Subsidiary or any successor (by  way of merger) thereto existing on the
  Issue Date shall assume or  otherwise become responsible for any
  Indebtedness of an entity which  is not a Subsidiary on the Issue Date,
  except to the extent that a Subsidiary would be permitted to incur such
  Indebtedness under this Section; and


           (viii)  Non-Recourse Indebtedness incurred by a foreign Subsidiary
  not constituting a Guarantor.

                   SECTION 4.05.  Limitation on Restricted Payments.

                            (a)  The Company will not, and will  not permit any
  of its Subsidiaries to, make  any Restricted Payment, unless at the  time of
  and after giving effect to  the proposed Restricted Payment, (i) no Default
  shall  have occurred and  be continuing (or would  result therefrom), (ii)
  the Company  could incur at least $1.00  of additional  Indebtedness under
  the tests described  in the first  sentence of Section  4.03 of this
  Indenture and  (iii) the aggregate amount of  all Restricted Payments
  declared or made  on or after  the Issue  Date by the Company or any
  Subsidiary shall  not exceed the sum of (A) 50% (or if such Consolidated Net
  Income shall  be a  deficit, minus  100% of  such deficit)  of the  aggregate
  Consolidated  Net Income  accrued during the period beginning on the  first
  day of the fiscal  quarter in which the Issue Date falls and  ending on  the
  last  day of  the fiscal  quarter  ending immediately  prior to  the date  of
  such  proposed Restricted Payment, minus 100% of the  amount of any
  writedowns, write-offs and  other negative extraordinary charges not
  otherwise reflected in Consolidated Net Income  during such period, plus (B)
  an  amount equal to the  aggregate net cash proceeds  received by the
  Company, subsequent to  the Issue Date, from the  issuance or sale  (other
  than to  a Subsidiary) of shares of its Capital Stock (excluding Redeemable
  Stock, but including Capital Stock issued upon  the exercise  of options,
  warrants or  rights to  purchase Capital  Stock (other than  Redeemable
  Stock) of the  Company) and  the liability  (expressed as a  positive number)
  as expressed on the  face of  a balance  sheet  in  accordance with  GAAP  in
  respect  of any  Indebtedness  of  the  Company  or  any of  its
  Subsidiaries, or  the carrying  value of  Redeemable Stock,  which has  been
  converted  into, exchanged for  or satisfied by the issuance  of shares of
  Capital Stock (other  than Redeemable Stock) of the Company, subsequent to
  the Issue  Date, plus  (C) 100% of  the net reduction  in Restricted
  Investments, subsequent to  the Issue Date, in any Person, resulting from
  payments of interest on Indebtedness, dividends,





                                       35
<PAGE>   43

  repayments  of loans  or advances,  or other  transfers  of  Property (but
  only to  the extent  such interest, dividends,  repayments or other transfers
  of Property are not included  in the calculation of Consolidated Net Income),
  in each case  to the Company or  any Subsidiary from  any Person (including,
  without  limitation, from Unrestricted  Subsidiaries) or  from redesignations
  of Unrestricted  Subsidiaries as  Subsidiaries (valued  in each case as
  provided in the definition of "Investments"), not to exceed in the case  of
  any Person the amount of Restricted Investments previously  made by the
  Company or  any Subsidiary in such  Person and in each  such case which was
  treated as a Restricted Payment.

                            (b)  The  foregoing provisions will  not prevent
  (i) the  payment of any  dividend on Capital Stock of any  class within 60
  days  after the date  of its declaration if  at the date  of declaration such
  payment would be  permitted by  this Indenture;  (ii) any  repurchase or
  redemption of Capital  Stock or Subordinated Indebtedness  of the Company or
  a Subsidiary made  by exchange for Capital  Stock of the  Company (other than
  Redeemable Stock), or out of the  net cash proceeds from  the substantially
  concurrent issuance or sale (other  than to a  Subsidiary) of Capital  Stock
  of the  Company (other than  Redeemable Stock),  provided that the net  cash
  proceeds from such sale are  excluded from computations under Section
  4.05(a)(iii)(B) above to  the extent  that such  proceeds  are applied  to
  purchase  or  redeem such  Capital Stock  or  Subordinated Indebtedness;
  (iii) so  long as  no  Default shall  have  occurred  and be  continuing  or
  should  occur  as a consequence thereof, any  repurchase or redemption of
  Subordinated Indebtedness of the Company  or a Subsidiary solely  in exchange
  for, or  out of  the net  cash proceeds  from the  substantially concurrent
  sale  of, new Subordinated Indebtedness  of  the Company  or  a  Subsidiary,
  so  long as  such  Subordinated Indebtedness  is permitted  under Section
  4.03 of this Indenture and (1) is subordinated to the Securities at least to
  the same extent as the Subordinated Indebtedness so  exchanged, purchased or
  redeemed, (2) has a stated maturity  later than the  stated maturity of the
  Subordinated Indebtedness  so exchanged, purchased or  redeemed and (3) has
  an Average  Life at  the time  incurred  that is  greater than  the
  remaining Average  Life of  the  Subordinated Indebtedness  so  exchanged,
  purchased  or  redeemed;  (iv)  Investments   in  any  Joint  Ventures,
  foreign Subsidiaries not  constituting Guarantors and  Indrillers in an
  aggregate amount not  to exceed $10,000,000 and (v) redemptions  of the
  Company's  Series A Preferred  Stock issued and  outstanding on the  Issue
  Date for an aggregate redemption price of not  more than $1,000,000.
  Notwithstanding  the foregoing, the  amount available for Investments in
  Joint Ventures  and foreign Subsidiaries pursuant to clause  (iv) of the
  preceding sentence may  be increased by the aggregate amount received by the
  Company and its Subsidiaries from a Joint Venture or a foreign Subsidiary  on
  or before such  date resulting from payments of interest on  Indebtedness,
  dividends, repayments  of loans  or  advances or  other  transfers of
  Property  made to  such  Joint Venture  or  foreign Subsidiary (but only to
  the extent such interest  dividends, repayments or other transfers of
  Property are not included in  the calculation  of  Consolidated Net  Income).
  Restricted  Payments permitted  to be  made  as described in  the first
  sentence  of this  Section 4.05(b) will  be  excluded in  calculating  the
  amount  of Restricted Payments  thereafter, except  that any such  Restricted
  Payments  permitted to be  made pursuant to clause  (iv) will be included  in
  calculating the  amount of  Restricted Payments made pursuant  to such clause
  (iv) thereafter.





                                       36
<PAGE>   44

                   (c)  For purposes  of this Section 4.05,  if a particular
  Restricted  Payment involves a non- cash payment,  including a  distribution
  of  assets, then  such Restricted  Payment shall  be deemed  to be  an amount
  equal to the cash portion of  such Restricted Payment, if  any, plus an
  amount equal to the Fair  Market Value of the non-cash portion of such
  Restricted Payment.

                            SECTION  4.06.   Limitation  on Dividends  and
  Other Payment  Restrictions Affecting Subsidiaries.  The  Company will not,
  and  will not permit any Subsidiary,  directly or indirectly, to  create,
  enter into  any agreement  with any  Person or  otherwise cause  or suffer
  to  exist or  become effective  any consensual encumbrance or restriction  of
  any kind which by its  terms restricts the ability of any  Subsidiary to (a)
  pay dividends,  in cash or otherwise,  or make  any other distributions  on
  its  Capital Stock  to the Company  or any Subsidiary, (b) pay any
  Indebtedness owed to the Company  or any Subsidiary, (c) make loans or
  advances to the  Company or any Subsidiary or (d) transfer any of its
  Property or assets  to the Company or any Subsidiary except any encumbrance
  or restriction contained in any agreement or instrument:

           (i)  existing on the Issue Date;

           (ii)  relating  to any Property or assets acquired  after the Issue
  Date, so  long as such encumbrance or restriction  relates  only to  the
  Property or  assets  so acquired  and is  not and  was  not created  in
  anticipation of such acquisition;

           (iii)  relating  to any Acquired Indebtedness of  any Subsidiary at
  the date on  which such Subsidiary was  acquired by  the Company  or any
  Subsidiary  (other than  Indebtedness incurred  in anticipation  of such
  acquisition);

           (iv)  effecting  a refinancing of Indebtedness  incurred pursuant to
  an  agreement referred to in  the foregoing  clauses (i)  through (iii),  so
  long as  the encumbrances  and restrictions  contained in  any such
  refinancing agreement  are no  more restrictive  than  the encumbrances  and
  restrictions contained  in  such agreements;

           (v)   constituting  customary provisions  restricting subletting  or
  assignment  of any  lease of  the Company  or  any  Subsidiary or  provisions
  in license  agreements  or similar  agreements  that restrict  the assignment
  of such agreement or any rights thereunder;

           (vi)    constituting  restrictions  on  the  sale  or  other
  disposition  of  any  Property  securing Indebtedness as a result of a
  Permitted Lien on such Property; or

           (vii)  constituting any temporary encumbrance or restriction with
  respect to a Subsidiary pursuant to an agreement that has been entered into
  for the sale or disposition of all or substantially all of the

  Capital Stock of, or Property and assets of, such Subsidiary.

                   SECTION 4.07.  Limitation on Asset Sales.

                            The Company will not engage in, and will not permit
  any Subsidiary to engage  in, any Asset Sale  unless (a) except in  the case
  of  (i) an Asset Sale  resulting from the  requisition of title to, seizure
  or forfeiture of any Property or assets or any actual or constructive





                                       37
<PAGE>   45

  total  loss or an agreed or compromised  total loss or (ii)  a Bargain
  Purchase Contract,  the Company or such Subsidiary, as the case may be,
  receives consideration at the time  of such Asset Sale at least equal to  the
  Fair Market Value  of the Property; (b) at least 75% of  such consideration
  consists of Cash  Proceeds (or the assumption of  Indebtedness of the
  Company or such  Subsidiary relating to  the Capital Stock  or Property  or
  asset  that was the subject of such Asset Sale and the unconditional release
  of the Company or such Subsidiary from such Indebtedness); (c) after giving
  effect to such Asset Sale, the total non-cash consideration held  by the
  Company from  all  such Asset  Sales does  not exceed  $10,000,000; and  (d)
  the  Company delivers  to the Trustee an Officers' Certificate certifying
  that  such Asset Sale complies with clauses (a), (b) and (c).  The Company or
  such Subsidiary, as the case may be, may  apply the Net Available Proceeds
  from each  Asset Sale (x) to the  acquisition of one or  more Replacement
  Assets, or (y)  to repurchase  or repay  Senior Debt (with  a permanent
  reduction  of  availability  in  the  case  of revolving  credit
  borrowings);  provided  that such acquisition or  such repurchase  or
  repayment  shall be  made within  365 days  after the  consummation of  the
  relevant Asset Sale.  Any Net Available  Proceeds from  any Asset  Sale
  that  are not  used to  so  acquire Replacement Assets or  to repurchase or
  repay  Senior Debt within 365 days  after consummation of the  relevant Asset
  Sale constitute "Excess Proceeds".

                   (b)      When the  aggregate amount of Excess Proceeds
  exceeds $15,000,000, the Company shall within 30  days  thereafter, or  at
  any time  after  receipt  of  Excess Proceeds  but  prior to  there  being
  $15,000,000 of Excess Proceeds,  the Company may, at its option,  make a pro
  rata offer (an "Asset Sale Offer") to purchase from all holders  an aggregate
  principal amount of  Securities equal to the Excess  Proceeds, at a price in
  cash (the "Asset Sale Offer Purchase Price") equal to 100%  of the
  outstanding  principal amount  at Stated Maturity  thereof plus accrued
  interest,  if any, to  the Asset Sale Purchase  Date, in accordance  with the
  procedures set forth in Section 4.07(c).

            (c)             Within 30 days  of the date that  the amount of
  Excess  Proceeds exceeds $15,000,000, the Company, or  the Trustee at  the
  request and expense of  the Company, shall send  to each Holder  by first
  class mail, postage prepaid, a notice prepared by the Company stating:

                     (i)            that an  Asset Sale Offer  is being made
           pursuant  to this Section  4.07 and that all Securities properly
           tendered will be accepted for payment, subject to proration in the
           event that the amount of Excess Proceeds is less than the aggregate
           Asset Sale Offer  Purchase Price of all Securities properly tendered
           pursuant to the Asset Sale Offer;

                     (ii)           the Asset Sale Offer  Purchase Price, the
           amount  of Excess Proceeds that are available to be  applied to
           purchase tendered Securities, and the  date Securities are to be
           purchased pursuant to the Asset Sale Offer (the "Asset Sale Offer
           Purchase Date"), which date shall  be a date no earlier than 30 days
           and not later than 40 days subsequent to the date such notice is
           mailed;

                     (iii)          that  any Securities or  portions thereof
           not properly  tendered or accepted for payment will continue to
           accrue interest;





                                       38
<PAGE>   46

                     (iv)           that, unless  the Company  defaults in  the
           payment  of the Asset  Sale Offer Purchase Price with respect
           thereto, all Securities or portions  thereof accepted for payment
           pursuant to the Asset Sale Offer  shall cease to accrue interest
           from  and after the Asset Sale Offer  Purchase Date;

                     (v)            that  any  Holder  electing  to  have any
           Securities  or  portions  thereof purchased pursuant to  the Asset
           Sale Offer  will be required to  surrender such Securities, with
           the form  entitled "Option of Holder  to Elect Purchase" on the
           reverse of  such Securities completed, to the Paying Agent at the
           address specified  in the notice, prior to the close of business  on
           the third Business Day preceding the Asset Sale Offer Purchase Date;

                     (vi)           that any  Holder shall be  entitled to
           withdraw such election  if the Paying Agent receives, not later than
           the  close of business on the  second Business Day preceding the
           Asset Sale Offer Purchase Date, a telegram, telex, facsimile
           transmission  or letter, setting forth the name of the Holder, the
           principal amount of Securities delivered  for purchase, and a
           statement  that such Holder is withdrawing  such Holder's election
           to have such  Securities or portions  thereof purchased pursuant to
           the Asset Sale Offer;

                     (vii)          that  any Holder electing to have
           Securities purchased  pursuant to the Asset Sale Offer must  specify
           the principal amount at Stated Maturity  that is being tendered for
           purchase, which principal amount at Stated Maturity must be $1,000
           or an integral multiple thereof;

                     (viii)         if  Certificated Securities  have been
           issued pursuant  to Section 2.06(a), that any Holder of Certificated
           Securities whose Certificated Securities are being purchased  only
           in part will be issued  new Certificated Securities equal in
           principal amount at Stated Maturity  to the unpurchased portion of
           the Certificated Security  or Securities surrendered, which
           unpurchased portion will be equal in principal amount at Stated
           Maturity to $1,000 or an integral multiple thereof;

                     (ix)           that the Trustee  will return  to the
           Holder of  a Global  Security that  is being  purchased in  part,
           such Global  Security with a  notation on Schedule A  thereof
           adjusting the principal amount at  Stated Maturity thereof  to be
           equal  to the unpurchased  portion of such  Global Security; and

                     (x)            the instructions and any other  information
           necessary to enable any Holder to tender Securities and to have such
           Securities purchased, or to withdraw such tender, pursuant  to this
           Section 4.07.

            (d)             If the  aggregate Asset Sale  Offer Purchase Price
  of the Securities  surrendered by Holders exceeds the amount of Excess
  Proceeds as indicated in the notice required by Section 4.07(c)  hereof, the
  Trustee shall select the Securities to be purchased  on a pro rata basis
  based on  the principal amount of the Securities tendered, with such
  adjustments as





                                       39
<PAGE>   47

  may  be deemed appropriate  by the  Trustee and  to comply  with any
  securities exchange and  other applicable requirements,  so that  only
  Securities  in denominations  of $1,000  or  integral  multiples thereof
  shall be purchased.

            (e)             On or before  the Asset Sale  Offer Purchase Date,
  the Company shall (i) accept  for payment any Securities or portions thereof
  properly tendered and selected for purchase pursuant to the  Asset Sale  and
  Section 4.07(d) hereof; (ii) irrevocably deposit  with the Paying Agent, by
  10:00 a.m., New York City time, on such date, in immediately available
  funds, an amount equal to the Asset Sale Offer Purchase Price in respect  of
  all Securities or  portions thereof so  accepted; and  (iii) deliver, or
  cause to  be delivered, to the  Trustee the  Securities so  accepted together
  with an  Officers'  Certificate  listing the  Securities or portions thereof
  tendered to the Company and  accepted for payment.  The  Paying Agent shall
  promptly send  by first class mail, postage  prepaid, to each Holder of
  Securities  or portions thereof so accepted for  payment, payment in an
  amount equal  to the Asset Sale Offer Purchase Price for  such Securities or
  portions   thereof.  The  Company shall publicly announce  the results of the
  Asset Sale Offer on or as  soon as practicable after the Asset Sale  Offer
  Purchase Date.  For  purposes of this Section 4.07, the Trustee shall  act as
  the Paying Agent.

            (f)             Upon surrender  and cancellation  of a
  Certificated  Security that  is purchased  in part, the Company  shall
  promptly issue  and the  Trustee shall authenticate  and deliver to  the
  surrendering Holder of such Certificated Security a  new Certificated
  Security equal in  principal amount to the unpurchased portion of  such
  surrendered Certificated Security; provided  that each such new Certificated
  Security shall be in a principal amount at Stated Maturity of $1,000 or an
  integral multiple thereof.

            Upon surrender of a Global Security that  is purchased in part
  pursuant to an  Asset Sale Offer, the Paying  Agent shall  forward such
  Global Security  to  the  Trustee who  shall make  a notation  on Schedule A
  thereof to reduce the principal amount  of such Global Security to an amount
  equal to the  unpurchased portion of such Global Security, as provided in
  Section 2.05 hereof.

            (g)             Upon completion of  an Asset Sale  Offer (including
  payment  of the Asset  Sale Offer Purchase Price  for accepted Securities),
  any surplus Excess  Proceeds that were subject to  such offer shall cease to
  be  Excess Proceeds, the amount of Excess Proceeds shall be reset to zero and
  the Company may use any remaining amount for general corporate purposes.

                   (h)      The Company shall comply  with any applicable
  tender offer  rules (including, without limitation, any applicable
  requirements of Rule 14e-1 under  the Exchange Act) in the event  that an
  Asset Sale Offer is required under the circumstances described herein.

                   SECTION 4.08.   Limitation on  Transactions with Affiliates.
  (a)  Subsequent  to the  Issue Date,  the Company  will not,  and will not
  permit any Subsidiary  to, directly  or indirectly, enter  into or permit  to
  exist any  transaction  or series  of related  transaction  (including, but
  not  limited  to, the purchase, sale or  exchange of  Property, the making
  of any  Investment, the  giving of  any guarantee or  the rendering of any
  service with any Affiliate of





                                      40
<PAGE>   48

  the Company, other than  transactions among the Company  and any Guarantors
  or  any Wholly Owned Subsidiaries) unless (i) such transaction or series of
  related transactions is on terms no  less favorable to the Company or such
  Subsidiary than those that could be obtained  in a comparable arm's length
  transaction with a Person that is not such  an Affiliate and (ii)  (A) with
  respect to a transaction  or series of related  transactions that has a  Fair
  Market Value in excess  of $2,000,000 but less than $5,000,000, the  Company
  delivers an Officers' Certificate to the Trustee  certifying that such
  transaction  or series of related  transactions complies  with clause (i)
  above;  or (B) with  respect to a transaction or  series  of related
  transactions that has  a Fair Market  Value equal  to or  in excess  of
  $5,000,000,  the transaction  or series  of related  transactions  is
  approved  by a majority of  the Board of Directors  of the Company
  (including a  majority of the disinterested directors), which approval  is
  set forth in  a Board Resolution certifying that  such transaction or series
  of transactions complies with clause (i) above.

                   (b)      The foregoing  provisions shall  not be  applicable
  to  (i) reasonable and  customary compensation, indemnification  and other
  benefits paid  or made  available to an officer,  director or employee of the
  Company  or a Subsidiary  for services rendered  in such person's  capacity
  as an  officer, director or employee (including  reimbursement  or
  advancement  of reasonable  out-of-pocket  expenses and  provisions  of
  directors   and  officers   liability insurance)  or  (ii) the  making  of
  any  Restricted Payment  otherwise permitted by this Indenture.

                   SECTION 4.09.  Change of Control.

                   (a)      Upon  the occurrence  of a  Change of  Control,
  each  Holder will  have the  right to require the  Company to repurchase all
  of such Holder's Securities in whole or in  part (the "Change of Control
  Offer")  at a purchase price (the "Change of Control Purchase Price")  in
  cash equal to 101% of the aggregate principal amount at Stated  Maturity
  thereof, plus accrued and unpaid  interest thereon, if any, to the  Change of
  Control Payment Date on the terms described below.

                   (b)      Within 30 days following  any Change of Control,
  the  Company or the Trustee  (at the expense of the Company) will mail a
  notice to each Holder and to the Trustee stating,

                     (i)            that a Change of  Control has occurred and
           a Change of Control Offer is being made  pursuant to  this Section
           4.09,  and that,  although Holders  are not  required to  tender
           their Securities, all Securities that are timely tendered will be
           accepted for payment;

                     (ii)           the Change of Control Purchase Price and
           the  repurchase date, which will  be no earlier  than 30 days and no
           later than  60 days after the date such  notice is mailed (the
           "Change of Control Payment Date");

                     (iii)          that any Security  or portion thereof
           accepted for  payment pursuant to  the Change of  Control Offer (and
           duly paid  for on the  Change of  Control Payment  Date) will cease
           to accrue interest after the Change of Control Payment Date;





                                       41
<PAGE>   49

                     (iv)           that any Security or portion  thereof not
           properly tendered  will continue to accrue interest;

                     (v)            that  any  Holder  electing  to  have any
           Securities  or  portions  thereof purchased pursuant to a  Change of
           Control Offer will  be required to surrender such  Securities, with
           the form entitled  "Option  of Holder to Elect Purchase"   on the
           reverse of such  Securities completed, to the Paying Agent  at the
           address specified  in the notice,  prior to the close  of business
           on  the third Business day preceding the Change of Control Date;

                     (vi)           that  any Holder shall be entitled  to
           withdraw such election  if the Paying Agent receives, not later
           than the close of business on the second  Business Day preceding the
           Change of Control Payment Date, a  telegram, telex, facsimile
           transmission or letter, setting  forth the name of the Holder, the
           principal amount of Securities delivered  for purchase, and a
           statement  that such Holder is  withdrawing such Holder's election
           to have such  Securities or portions  thereof purchased pursuant to
           the Change of Control Offer;

                     (vii)          that any Holder electing  to have
           Securities purchased pursuant to the Change of Control Offer  must
           specify  the principal amount  at Stated  Maturity that is  being
           tendered  for purchase, which principal amount at Stated Maturity
           must be $1,000 or an integral multiple thereof;

                     (viii)         if  Certificated Securities  have been
           issued pursuant  to Section  2.06(a), that any Holder  of
           Certificated Securities whose Certificated Notes are  being
           purchased only in part will  be issued  new  Certificated Securities
           equal in  principal amount  at  Stated Maturity  to the unpurchased
           portion  of the Certificated Security or Securities surrendered,
           which unpurchased portion will be equal in principal amount at
           Stated Maturity to $1,000 or an integral multiple thereof;

                     (ix)           that  the Trustee  will return to  the
           Holder  of a Global Security  that is being purchased in part, such
           Security  with a notation on Schedule A thereof adjusting  the
           principal amount at Stated Maturity thereof to be equal to the
           unpurchased portion of such Global Security;

                     (x)            the instructions and any other information
           necessary to enable any Holder  to accept a Change of Control Offer
           or effect withdrawal of such acceptance; and

                     (xi)           the  instructions and any  other
           information necessary to  enable Holders to tender their Securities
           and have such Securities purchased pursuant to the Change of Control
           Offer.

            (c)             On or before the  Change of Control  Payment Date,
  the  Company shall (i) accept  for payment  any Securities  or  portions
  thereof  properly  tendered pursuant  to  the Change  of  Control  Offer;
  (ii) irrevocably deposit with the Paying Agent, by 10:00 a.m., New





                                       42
<PAGE>   50

  York City  time, on  such date,  in immediately  available funds,  an  amount
  equal  to the  Change of  Control Purchase  Price  in  respect  of all
  Securities  or  portions  thereof  so  accepted,  including interest,  if
  applicable; and (iii) deliver,  or cause to be  delivered, to the Trustee the
  Securities so  accepted together with an Officers' Certificate listing the
  Securities  or portions thereof tendered to the Company and accepted for
  payment.  The Paying  Agent shall promptly send  by first class mail, postage
  prepaid,  to each Holder of Securities or portions  thereof so accepted for
  payment, payment in  an amount equal to the  Change of Control Purchase Price
  for such  Securities or portions thereof.   The Company  shall publicly
  announce the  results of the Change  of Control  Offer on or  as soon  as
  practicable after  the Change  of Control Payment  Date.   For purposes of
  this Section 4.09, the Trustee shall act as the Paying Agent.

            (d)             Upon surrender and cancellation of a  Certificated
  Security that is purchased in part pursuant to the Change  of Control Offer,
  the Company shall  promptly issue and the Trustee shall  authenticate and
  deliver  to the  surrendering Holder  of such  Certificated  Security, a  new
  Certificated  Note equal  in principal  amount  at Stated  Maturity  to  the
  unpurchased  portion  of such  surrendered Certificated  Note; provided that
  each such new  Certificated Security shall be in a  principal amount of
  $1,000 at Stated Maturity or an integral multiple thereof.

            Upon surrender  of a  Global Security  that is  purchased in  part
  pursuant  to a  Change of  Control Offer, the  Paying Agent  shall forward
  such  Global Security  to the  Trustee who  shall make  a notation  on
  Schedule A thereof to reduce the  principal amount at Stated Maturity  of
  such Global Note to  an amount equal to the unpurchased portion of such
  Global Security, as provided in Section 2.05 hereof.

                            (e)     The Company  will not be required  to make
  a Change  of Control  Offer upon a Change  of Control  if a  third party
  makes the  Change of  Control Offer  in the  manner, at  the  times and
  otherwise in compliance with  the requirements set forth  in this Indenture
  applicable to a Change  of Control Offer made by the Company and  repurchases
  all Securities validly tendered and not withdrawn under such  Change of
  Control Offer.

                            (f)     The Company will  comply with any
  applicable tender offer  rules (including, without limitation, any
  applicable requirements of Rule  14e-1 under the Exchange Act)  in the event
  that  the Change of Control Offer is triggered under the circumstances
  described herein.

                   SECTION 4.10.    Limitation on  Liens.    The  Company  will
  not,  and will  not  permit  any Subsidiary to, directly  or indirectly,
  create, affirm, incur, assume or suffer to exist any  Liens of any kind other
  than Permitted Liens  on or with respect  to any Property or assets of the
  Company  or such Subsidiary or any  interest therein  or any  income or
  profits therefrom,  whether owned  at the  Issue Date  or  thereafter
  acquired, without effectively  providing that  the Securities shall  be
  secured equally and  ratably with  (or prior to) the Indebtedness so secured
  for so long as such obligations are so secured.





                                       43
<PAGE>   51
                   SECTION 4.11.   Limitation  on Guarantees  by Guarantors.
  The  Company will not  permit any Guarantor to  guarantee the  payment of
  any Subordinated  Indebtedness of  the Company  unless such  guarantee shall
  be  subordinated  to  such Guarantor s  Guarantee  at least  to  the same
  extent as  such  Subordinated Indebtedness is subordinated  to the
  Securities;  provided that  this covenant will  not be applicable  to any
  guarantee  of any  Guarantor that  (i) existed at  the time  at which such
  Person  became a  Subsidiary of the Company  and (ii)  was  not incurred  in
  connection with,  or  in contemplation  of,  such Person  becoming  a
  Subsidiary of the Company.

                   SECTION 4.12  Unrestricted Subsidiaries

                   (a)      The Company  may designate a subsidiary  (including
  a newly formed  or newly acquired subsidiary)  of  the  Company  or  any  of
  its  Subsidiaries as  an  Unrestricted  Subsidiary;  provided  that (i)
  immediately  after  giving effect  to  the  transaction,  the  Company  could
  incur $1.00  of  additional Indebtedness pursuant  to  the  first sentence
  of  Section 4.03  and (ii) such  designation  is  at  the  time permitted
  under  Section 4.05.    Notwithstanding any  provisions  of this  covenant
  all  subsidiaries  of  an Unrestricted Subsidiary will be Unrestricted
  Subsidiaries.

                   (b)      The  Company will  not, and  will not  permit any
  of its  Subsidiaries to,  take any action or enter  into any transaction or
  series of transactions that  would result in a  Person (other than a newly
  formed subsidiary  having no  outstanding Indebtedness  (other  than
  Indebtedness to  the Company  or a Subsidiary)  at  the date  of
  determination)  becoming  a Subsidiary  (whether  through  an  acquisition,
  the redesignation of  an  Unrestricted Subsidiary  or otherwise)  unless,
  after  giving effect  to  such  action, transaction or  series of
  transactions  on a pro  forma basis, (i) the  Company could incur at least
  $1.00 of additional Indebtedness  pursuant to  the first  sentence of
  Section 4.03  and (ii)  no Default  or Event  of Default would occur.

                   (c)      Subject to Sections 4.12(a) and  (b), an
  Unrestricted Subsidiary may  be redesignated as  a Subsidiary.   The
  designation  of a subsidiary  as an  Unrestricted Subsidiary  or the
  designation of an Unrestricted Subsidiary  as a Subsidiary  in compliance
  with this  Section 4.12 shall be  made by  the Board of Directors  pursuant
  to a Board  Resolution delivered  to the  Trustee and  shall be effective  as
  of  the date specified in such  Board Resolution, which shall not  be prior
  to the date  such Board Resolution is delivered to  the Trustee.   Any
  Unrestricted  Subsidiary shall become a  Subsidiary if it  incurs any
  Indebtedness other than Non-Recourse  Indebtedness.    If  at  any time
  Indebtedness  of  an Unrestricted  Subsidiary  which  was Non-Recourse
  Indebtedness no  longer so qualifies,  such Indebtedness shall be  deemed to
  have been incurred when such Non-Recourse Indebtedness becomes Indebtedness.

                   SECTION  4.13   Limitation on Sale  and Lease-Back
  Transactions.   The Company  will not, and will  not permit any Subsidiary
  to, directly or indirectly, enter  into, assume, guarantee or otherwise
  become liable with respect to  any Sale and Lease-Back Transaction unless (i)
  the proceeds from such Sale and Lease-Back Transaction  are at least equal
  to the Fair  Market Value of such Property being transferred and (ii) the
  Company or





                                       44
<PAGE>   52
  such Subsidiary would  have been permitted  to enter  into such transaction
  under the provisions  of Sections 4.03, 4.04 and 4.10.

                   SECTION  4.14    Limitation  on  Line  of  Business.   None
  of  the  Company  or any  of  its Subsidiaries will  directly or indirectly
  engage to any substantial  extent in any  line or  lines of business activity
  other than a Related Business.

                   SECTION 4.15.  Maintenance  of Office or  Agency.  The
  Company  shall maintain in The City  of New York, an office or agency  where
  Securities may be presented or  surrendered for payment, where  Securities
  may  be surrendered for  registration of  transfer or  exchange and  where
  notices and  demands to or  upon the Company  in respect of  the Securities
  and  this Indenture may  be served.  Unless otherwise  designated by the
  Company by written  notice to the Trustee  such office or agency  shall be
  the office  of the Trustee's agent, Texas  Commerce Trust Company  of New
  York, which is  located at  55 Water  Street, North  Building, Room 234,
  Windows 20 and 21, New York, New York   10041, Attention:  Vice President,
  Global  Trust Services.  The Company shall  give prompt written  notice to
  the Trustee  of the location,  and any  change in the  location, of such
  office or agency.   If at any time  the Company shall fail  to maintain any
  such required office or  agency or shall  fail  to  furnish the  Trustee with
  the address  thereof, such  presentations, surrenders,  notices and demands
  may  be made or served at  the Corporate Trust Office of the Trustee, and
  the Company hereby appoints the Trustee its agent to receive all
  presentations, surrenders, notices and demands.

                   The Company may  also from time to time  designate one or
  more  other offices or  agencies (in or outside of  The City of New York)
  where the Securities may  be presented or surrendered for any or  all of such
  purposes, and  may from  time to time  rescind such  designations; provided
  that no  such designation  or rescission  shall in any manner relieve the
  Company of  its obligation to maintain an  office or agency in The City of
  New  York, for such purposes.  The Company shall give prompt written notice
  to  the Trustee of any such designation and any change in the location of any
  such other office or agency.

                   SECTION 4.16.  Money  for the Security  Payments to be  Held
  in Trust.   If the  Company, any Subsidiary  of the Company or  any of their
  respective  Affiliates shall at any  time act as Paying Agent with respect to
  the Securities,  such Paying Agent  shall, on  or before  each due date  of
  the  principal of (and premium,  if any) or  interest on any of the
  Securities, segregate and hold  in trust for  the benefit of the Persons
  entitled thereto money  sufficient to pay the  principal (and premium, if
  any) or  interest so becoming due until such  money shall be paid to  such
  Persons or  otherwise disposed of as  herein provided, and  shall promptly
  notify the Trustee of its action or failure so to act.

                   Whenever the Company shall have one  or more Paying Agents
  with  respect to the Securities, it shall, prior to  or on  each due  date of
  the  principal of  (and premium, if  any) or interest  on any of  the
  Securities,  deposit with  a Paying  Agent a  sum sufficient  to pay  the
  principal  (and  premium, if  any) or interest so becoming  due, such  sum to
  be held  in trust  for the  benefit of  the Persons  entitled to  such
  principal, premium or interest, and (unless such Paying





                                       45
<PAGE>   53
  Agent  is the Trustee) the Paying  Agent shall promptly notify the Trustee of
  the Company's action or failure so to act.

                   SECTION  4.17.    Corporate  Existence.    The  Company
  will, and  will  cause  each  of  its Subsidiaries  to, preserve  and keep
  in full  force and  effect its  corporate existence  in  accordance with
  applicable  law, except  as  permitted in  Sections 5.01  and 5.02;
  provided, however,  that the  Company may terminate the corporate existence
  of any Subsidiary  if, in the good faith judgment of  the Board of Directors
  of  the Company,  such  termination is  desirable  in the  conduct  of the
  business  of the  Company  and  its Subsidiaries and is not disadvantageous
  in any material respect to the Holders of the Securities.

                   SECTION  4.18  Maintenance  of Property.  The  Company shall
  cause  all Property  used in the conduct of  its  business or  the business
  of any  of its  Subsidiaries to  be maintained  and  kept in  good condition,
  repair and  working order  (reasonable wear  and tear  excepted) and
  supplied  with  all necessary equipment  and shall  cause  to  be  made  all
  necessary  repairs, renewals,  replacements,  betterments  and improvements
  thereof, all as, in the judgment of  the Company, may be necessary  so that
  the business carried on in connection therewith  may be properly and
  advantageously conducted at all  times; provided that nothing in this Section
  4.18 shall prevent the Company from  discontinuing the operation or
  maintenance of  any of such Property if such discontinuance  is, in the
  judgment of the Company, desirable in the  conduct of its business or the
  business of any of its Subsidiaries  and not disadvantageous in any material
  respect  to the Holders of the Securities.

                   SECTION 4.19.   Payment of  Taxes and Other  Claims.  The
  Company shall pay  or discharge  or cause to  be paid or discharged, before
  the  same shall become delinquent,  (a) all material taxes, assessments and
  governmental charges  levied or  imposed upon the Company  or any of its
  Subsidiaries or upon the  income, profits  or property of the Company  or any
  of its Subsidiaries  and (b) all material lawful claims for labor, materials
  and  supplies which,  if unpaid,  might by  law become  a Lien  upon the
  Property or  assets of the Company or any of its  Subsidiaries; provided that
  the  Company shall not be  required to pay or  discharge or cause to  be paid
  or discharged  any such  tax, assessment,  charge or  claim whose  amount,
  applicability  or validity  is being  contested in  good faith by
  appropriate proceedings  and for  which adequate  reserves in accordance with
  GAAP or other appropriate provision has been made.

  SECTION 4.20  Compliance Certificate; Notice of Default or Event of Default.

                   (a)      The  Company shall  deliver to  the Trustee  within
  120  days after  the end  of each fiscal year of the Company  ending after
  the date hereof,  an Officers'  Certificate (which shall  be signed by
  officers satisfying  the requirements of Section  314 of the  Trust Indenture
  Act) stating  whether or not,  to the  best knowledge of such  officers, the
  Company  has complied  with all conditions and  covenants under this
  Indenture, and, if the  Company shall be  in Default,  specifying all such
  Defaults  and the nature thereof  of which such officer may have knowledge.

                   (b)      The year-end financial statements  delivered
  pursuant to Section 4.02 above  shall be accompanied by a written statement
  of the Company's independent public





                                       46
<PAGE>   54
  accountants (who  shall be a firm  of established  national reputation
  reasonably satisfactory  to the Trustee) that in  making the examination
  necessary for certification of  such financial statements nothing  has come
  to their attention which would lead them to believe that the Company or any
  of its  Subsidiaries has violated the provisions of Section 4.01, 4.03,
  4.04, 4.05, 4.07, 4.09 or 4.17 hereof or of Article 5 of  this Indenture or,
  if  any such  violation  has  occurred,  specifying  the  nature and  period
  of  existence thereof,  it  being understood  that such accountants shall not
  be liable directly or indirectly  to any person for any failure to obtain
  knowledge of  any such  violation, and  it  being  further understood  that
  such  statement may  not be provided to the extent contrary to the then
  current recommendations of the accountants  governing body.

                   (c)      The Company will,  so long as any  of the
  Securities are outstanding,  deliver to the Trustee, within 5 days of any
  Officer becoming aware of (i) any Default  or Event of Default or (ii) any
  event of  default under  any other mortgage,  indenture or instrument
  referred to in Section  6.01(e), an Officers' Certificate specifying such
  Default,  Event of Default or  other event of  default and what action  the
  Company or applicable Subsidiary is taking or proposes to take with respect
  thereto.

                   SECTION 4.21.  Further Instruments  and Acts.  Upon request
  of  the Trustee, the Company will execute and  deliver such  further
  instruments  and do  such further  acts as  may be  reasonably necessary  or
  proper to carry out more effectively the purpose of this Indenture.

                   SECTION  4.22.  Prohibition on Company  and Guarantors
  Becoming Investment Companies.  None of the Company or the  Guarantors shall
  become an   investment company  as  defined in the Investment  Company Act of
  1940, as amended.

                   SECTION 4.23.   Stay,  Extension and  Usury Laws.   The
  Company and each  of the  Guarantors covenant (to the extent  that it may
  lawfully do so) that it shall  not at any time insist upon,  plead, or in any
  manner whatsoever claim or  take the benefit of  advantage of, any  stay,
  extension  or usury law wherever enacted, now or at  any time hereafter  in
  force,  that may affect  the covenants or  the performance of  this
  Indenture; and  the Company and each  of the  Guarantors (to the  extent that
  it may  lawfully do so)  hereby expressly waive all benefit  or advantage of
  any such law,  and covenants that it shall  not, by resort to any such  law,
  hinder, delay or impede the execution of any power herein  granted to the
  Trustee, but shall suffer and permit the execution of every such power as
  though no such law has been enacted.


                                   ARTICLE 5

              Consolidation, Merger, Conveyance, Lease or Transfer

     SECTION 5.01.  Consolidation, Merger, Conveyance, Lease or Transfer.

                   (a)      The Company  will not, in any transaction or series
  of transactions, consolidate with or  merge into any other Person (other than
  a  merger of a Subsidiary into the Company in which the Company is the
  continuing corporation), or continue in any new





                                       47
<PAGE>   55
  jurisdiction, or sell,  convey, assign, transfer, lease  or otherwise dispose
  of all or  substantially all of the Property and assets of the Company and
  the Subsidiaries, taken as a whole, to any Person, unless

                            (i)     either (A)  the  Company  shall  be the
                   continuing  corporation or  (B)  the corporation (if  other
                   than  the Company)  formed by  such  consolidation or  into
                   which  the Company is merged,  or the Person which acquires,
                   by sale, assignment, conveyance,  transfer, lease  or
                   disposition, all or substantially all of the Property and
                   assets of the Company and the Subsidiaries,  taken as a
                   whole  (such corporation  or Person,  the  Surviving  Entity
                   ), shall be a corporation organized and  validly existing
                   under the laws  of the United States of America, any
                   political subdivision thereof  or any state thereof or the
                   District of  Columbia, and shall expressly  assume, by a
                   supplemental indenture, the due and punctual  payment of the
                   principal of (and premium, if any)  and interest on all the
                   Securities and the performance of the Company s covenants
                   and obligations under this Indenture;

                            (ii)    immediately  before and after giving effect
                   to such  transaction or series of transactions on a  pro
                   forma basis (including,  without limitation, any
                   Indebtedness  incurred or  anticipated to be incurred in
                   connection with or in respect  of such transaction or series
                   of transactions), no  Event of Default  or Default  shall
                   have occurred  and be continuing  or would result therefrom;

                            (iii)   immediately  after   giving  effect   to
                   such   transaction  or  series   of transactions on a pro
                   forma basis (including,  without limitation, any
                   Indebtedness  incurred or anticipated to be incurred in
                   connection with or in respect  of such transaction or series
                   of transactions),  the Company  (or the  Surviving Entity if
                   the Company  is not continuing) shall have a Consolidated
                   Net Worth equal to  or greater than the  Consolidated Net
                   Worth of the Company immediately prior to such transactions;
                   and

                            (iv)    immediately  after  giving  effect  to  any
                   such  transaction  or  series of transactions  on a  pro
                   forma  basis as  if such  transaction  or  series of
                   transactions had occurred on the  first day of the
                   Determination Period,  the Company (or the Surviving  Entity
                   if  the  Company  is  not continuing)  would  be  permitted
                   to  incur  $1.00  of  additional Indebtedness pursuant to
                   the provisions of the first sentence of Section 4.03.

                   (b)      The  provision  of  Section 5.01(a)(iv)  above
  shall not  apply  to  any  merger  or consolidation  into or with, or  any
  such transfer of all or  substantially all of the  Property and assets of the
  Company and the Subsidiaries taken as a whole into, the Company.

                   SECTION  5.02.    Officers'  Certificate and  Opinion  of
  Counsel   In  connection  with any consolidation, merger,  continuance,
  transfer  of assets or  other transactions  contemplated by  Section 5.01,
  the Company shall deliver, or cause to be delivered, to the





                                       48
<PAGE>   56
  Trustee, in  form  and substance  reasonably  satisfactory  to the  Trustee,
  an  Officers'   Certificate and  an Opinion of  Counsel, each stating that
  such consolidation, merger,  continuance, sale, assignment, conveyance or
  transfer  and the supplemental  indenture in respect  thereto comply with the
  provisions  of this Indenture and that all conditions precedent in this
  Indenture relating to such transactions have been complied with.

                   SECTION  5.03.   Substitution  of  Surviving  Entity
  Upon  any  transaction  or series  of transactions  that are of  the type
  described in,  and are  effected in  accordance with, this  Article 5, the
  Surviving Entity  shall succeed to,  and be substituted for, and  may
  exercise every  right and power  of, the Company  under this Indenture and
  the  Securities with the  same effect as  if such Surviving  Entity had been
  named as the  Company in this Indenture; and when a Surviving  Person duly
  assumes all of  the obligations and covenants of the  Company pursuant to
  this  Indenture and the Securities, except in  the case of a  lease, the
  predecessor Person shall be relieved of all such obligations.

                   If such Surviving  Entity shall have succeeded to and  been
  substituted for the Company,  such Surviving Entity may  cause to be signed,,
  and may issue either  in its own name or  in the name of the Company prior to
  such succession any  or all of the Securities  delivered to the Trustee; and,
  upon the order  of such Surviving Entity,  instead of the Company,  and
  subject to  all the terms, conditions  and limitations in  this Indenture
  prescribed, the Trustee shall authenticate and shall deliver  any Securities
  which previously shall have  been signed and  delivered by  the officers of
  the Company  to the  Trustee for  authentication, and any Securities which
  such Surviving  Entity thereafter shall cause  to be signed  and delivered to
  the  Trustee for that  purpose (in  each instance  with endorsements  of
  Guarantees  thereon by  the Guarantors).   All  of  the Securities  so issued
  and so  endorsed shall in all  respects have the same  legal rank and benefit
  under this Indenture  as the Securities  theretofore or thereafter issued
  and endorsed in  accordance with  the terms of this Indenture and the
  Guarantee as though  all of such Securities had been issued and endorsed at
  the date  of the execution hereof.

                   In case of any  such consolidation, merger, continuance,
  sale, transfer, conveyance  or other disposal, such  changes  in  phraseology
  and  form  (but  not  in substance)  may  be  made in  the  Securities
  thereafter to be issued or the Guarantees to be endorsed thereon as may be
  appropriate.

                   For  all purposes of this Indenture and the Securities,
  Subsidiaries of any Surviving Entity will, upon such  transaction or series
  of transactions, become  Subsidiaries or Unrestricted Subsidiaries  as
  provided  pursuant to  this Indenture  and  all Indebtedness,  and all  Liens
  on Property  or assets,  of  the Surviving Entity  and its Subsidiaries
  immediately  prior to such transaction  or series  of transactions shall be
  deemed to have been incurred upon such transaction or series of transactions.





                                       49
<PAGE>   57

                                   ARTICLE 6

                             Defaults and Remedies

                   SECTION 6.01.  Events of Default.   Whenever used herein, an
  "Event of Default" means any  one of  the following events (whatever the
  reason for such Event of  Default and whether it shall be voluntary or
  involuntary or be  effected by operation of law or  pursuant to any judgment,
  decree  or order of any court or any order, rule or regulation of any
  administrative or governmental body):

                   (a)      default in  the payment of interest  on any
           Security pursuant to  this Indenture when the same becomes due and
           payable, and the continuance of such Default for a period of 30
           days;

                   (b)      default  in the payment  of principal of (or
           premium, if any,  on) any Security when the  same  becomes due  and
           payable,  whether  upon  Maturity,  upon  optional  redemption,
           required repurchase (including pursuant  to a Change of Control
           Offer or an Asset Sale Offer)  or otherwise or the failure  to make
           an offer to purchase any such  Security as required pursuant to the
           provisions of the Securities and this Indenture;

                   (c)      the Company fails  to comply  with any of  its
           covenants or  agreements contained  in Sections 4.03, 4.04, 4.05,
           4.07, 4.09, 4.13 and 5.01 of this Indenture;

                   (d)      the  Company defaults  in the  performance,  or
           breach, of  any covenant  or warranty of  the Company  in this
           Indenture  (other than a  covenant or warranty  addressed in clause
           (a), (b) or (c)  above) and continuance of such  Default or breach
           for a period of  30 days after  written notice  thereof has  been
           given to  the Company by  the Trustee or  to the Company and  the
           Trustee  by Holders  of at  least 25%  of the  aggregate principal
           amount  at Stated Maturity of the outstanding Securities;

                   (e)      Indebtedness  of the Company or any  Subsidiary is
           not paid  when due within the applicable grace period, if any,  or
           is accelerated by the  holders thereof and, in either case, the
           principal amount of such unpaid or accelerated Indebtedness exceeds
           $10,000,000;

                   (f)      the  entry  by  a  court  of  competent
           jurisdiction  of  one  or  more final judgments against  the Company
           or any  Subsidiary in an  uninsured or unindemnified aggregate
           amount  in excess of $5,000,000 which is not discharged,  waived,
           appealed, stayed, bonded or satisfied for a period of 60 consecutive
           days;

                   (g)      the entry  by a court having jurisdiction  in the
           premises of (i) a decree or order for  relief in respect of  the
           Company  or any Significant Subsidiary  in an involuntary case  or
           proceeding under U.S. bankruptcy laws, as now or  hereafter
           constituted, or any other applicable Federal, state, or foreign
           bankruptcy, insolvency,  or other similar law or  (ii) a decree or
           order adjudging the Company or any Significant




                                       50
<PAGE>   58
           Subsidiary a  bankrupt  or  insolvent,  or approving  as  properly
           filed a  petition  seeking reorganization, arrangement,  adjustment
           or  composition of or  in respect of  the Company  or any
           Significant  Subsidiary under U.S.  bankruptcy laws, as now or
           hereafter constituted, or any other  applicable Federal,  state or
           foreign bankruptcy,  insolvency, or similar  law, or appointing  a
           custodian,  receiver,  liquidator,  assignee,  trustee, sequestrator
           or  other similar  official of the Company or any  Significant
           Subsidiary or of any  substantial part of the Property  or assets of
           the Company  or any Significant Subsidiary, or ordering the winding
           up  or liquidation  of the  affairs  of  the Company  or any
           Significant Subsidiary,  and the continuance of  any such  decree
           or order  for  relief or  any such  other decree  or  order unstayed
           and in effect for a period of 60 consecutive days;

                   (h)      (i)  the commencement  by  the Company  or any
           Significant  Subsidiary  of a voluntary case  or proceeding under
           U.S. bankruptcy  laws, as now or hereafter constituted, or any
           other applicable Federal, state or  foreign bankruptcy, insolvency
           or  other similar law or  of any other case  or proceeding to  be
           adjudicated  a bankrupt or insolvent;  or (ii) the consent by the
           Company or any Significant  Subsidiary to the entry of  a decree or
           order  for relief  in respect  of the Company  or any Significant
           Subsidiary  in an  involuntary case or proceeding  under  U.S.
           bankruptcy  laws,  as  now  or hereafter  constituted,  or  any
           other applicable  Federal, state, or foreign bankruptcy, insolvency
           or other  similar law or to the commencement of any bankruptcy  or
           insolvency case or  proceeding against the Company or  any
           Significant Subsidiary; or (iii) the filing  by the Company or any
           Significant Subsidiary of a petition or answer or consent seeking
           reorganization  or relief under U.S. bankruptcy  laws, as  now  or
           hereafter  constituted,  or  any  other  applicable  Federal,  state
           or  foreign bankruptcy,  insolvency or  other similar  law; or  (iv)
           the  consent by  the Company  or any Significant Subsidiary  to the
           filing  of such  petition or to  the appointment of or  taking
           possession by a  custodian, receiver, liquidator, assignee, trustee,
           sequestrator  or similar official of  the Company  or any
           Significant Subsidiary  or of  any substantial  part of  the
           Property or  assets of the Company  or any Significant Subsidiary
           or of  any substantial part of the Property or assets of the Company
           or any Significant Subsidiary, or the  making by the Company or any
           Significant  Subsidiary of an  assignment for the benefit of
           creditors;  or (v) the admission  by the Company  or any Significant
           Subsidiary in  writing of its  inability to pay its  debts generally
           as they  become due; or  (vi) the taking of  corporate action by
           the Company or any Significant Subsidiary in furtherance of any such
           action; or

                   (i)      any Guarantee  shall for  any reason  cease to  be,
           or  be asserted  by  the Company  or any  Guarantor,  as applicable,
           not  to  be,  in full  force  and effect  (except pursuant to  the
           release  of any  such Guarantee  in accordance  with the  provisions
           of  this Indenture).

                   SECTION 6.02.   Acceleration.    If an  Event of  Default
  (other than  an  Event of  Default described in clause (g)  or (h) of Section
  6.01)  occurs and shall be continuing, then in each  and every case the
  Trustee  or the  Holders of  not less than  25% of  the outstanding
  aggregate principal amount at  Stated Maturity of the Securities may declare
  the principal amount at Stated





                                       51
<PAGE>   59
  Maturity of  the Securities to be  due and payable  immediately by a notice
  in writing to the  Company (and to the Trustee if  given by Holders  of such
  Securities), and upon any  such declaration the principal  amount at Stated
  Maturity of, premium, if any, on, any accrued and unpaid interest on, and any
  other amounts payable in respect of, the  Securities then outstanding will
  become and be immediately due and payable.   If any Event of Default
  specified in clause  (g) or (h) of  Section 6.01 occurs,  the principal
  amount at Stated Maturity  of, premium,  if any,  and any accrued  and unpaid
  interest  on, and any  other amount payable in  respect of, the Securities
  then outstanding shall become  immediately due and payable without any
  declaration or other act on the part  of the Trustee  or any Holder  of such
  Securities.   In the  event of a  declaration of  acceleration because an
  Event  of  Default set  forth  in  Section  6.01(e) above  has  occurred  and
  is  continuing,  such declaration of acceleration  shall be automatically
  rescinded and annulled  if the event of default  triggering such Event of
  Default  pursuant to Section 6.01(e) shall be remedied  or cured or waived
  by the holders of the relevant Indebtedness within 30 days after  such event
  of default; provided that no judgment or decree for  the payment of the money
  due on the Securities has been obtained by the Trustee as provided in this
  Indenture.

                   After  any such acceleration,  but before  a judgment  or
  decree  based on  acceleration, the Holders  of a  majority  in aggregate
  principal  amount at  Stated  Maturity of  the  Securities at  the  time
  outstanding may rescind and annul such acceleration if

                   (a)      the  Company or any Guarantor has paid or deposited
           with the Trustee a sum sufficient to pay

                            (i)     all money  paid  or  advanced by  the
                   Trustee  hereunder  and the  reasonable compensation,
                   expenses, disbursement and advances of the Trustee, its
                   agents and counsel,

                            (ii)    all overdue installments of  interest on
                   any other  amounts due in respect of all Securities;

                            (iii)   the principal  of (and premium, if any, on)
                   any Securities that have become due otherwise  than by
                   such declaration  of acceleration  and interest thereon at
                   the rate or rates prescribed therefor in the Securities and
                   this Indenture; and

                            (iv)    to  the  extent  that payment  of  such
                   interest is  lawful,  interest  upon Defaulted Interest  at
                   the  rate or  rates prescribed  therefor  in the  Securities
                   and  this Indenture;

                   (b)      all  Events of Default,  other than the  nonpayment
           of principal  of Securities which have become due solely  by such
           declaration of acceleration, have been cured  or waived as provided
           in Section 6.04;

                   (c)      the annulment of such  acceleration would not
           conflict with any judgment or decree of a court of competent
           jurisdiction; and





                                       52
<PAGE>   60
                   (d)      the Company has delivered  an Officers' Certificate
           to  the Trustee to the effect  of clauses (b) and (c) of this
           sentence.

           No such rescission shall affect any subsequent Default or impair any
right consequent thereto.

                   SECTION 6.03.  Other Remedies. If  an Event of Default
  occurs and is continuing, the  Trustee may pursue  any available remedy to
  collect the payment  of principal (and premium, if any) of or interest on,
  and any other  amounts then due in respect  of, the Securities or to  enforce
  the performance of any provision of the Securities or this Indenture.

                   The Trustee may maintain  a proceeding even if  it does not
  possess any of the  Securities or does  not produce  any of  them in  the
  proceeding.   A  delay or  omission by  the Trustee  or any  Holder in
  exercising any  right or remedy  accruing upon an  Event of Default shall
  not impair the  right or  remedy or constitute a waiver  of or acquiescence
  in  the Event of Default.  No remedy is  exclusive of any other remedy.  All
  available remedies are cumulative.

                   SECTION  6.04.  Waiver of  Past Defaults.   The Holders  of
  a majority in  principal amount at Stated Maturity of the Securities then
  outstanding by notice to  the Trustee may waive an existing  Default and its
  consequences except (i) a Default in the payment  of the principal of or
  interest on a Security or (ii) a Default in respect of  a provision  that
  under  Section 9.02  cannot be amended  without the  consent of  each Holder
  affected.   When a  Default is waived,  it is  deemed cured,  but no  such
  waiver  shall extend  to any subsequent or other Default or impair any
  consequent right.

                   SECTION 6.05.  Control by Majority.   The Holders of a
  majority in principal amount at  Stated Maturity  of  the  Securities then
  outstanding  may  direct the  time,  method  and place  of  conducting  any
  proceeding  for any  remedy available to  the Trustee  or of  exercising any
  trust or  power conferred  on the Trustee.  However, the  Trustee may refuse
  to follow any direction  that conflicts with law or  this Indenture or,
  subject to  Section 7.01,  that  the Trustee  determines is  unduly
  prejudicial to  the rights  of  other Holders, it being understood that the
  Trustee shall have no  duty to ascertain whether or not such  actions or
  forbearances  are unduly  prejudiced to  such Holders,  or would  involve
  the  Trustee in  personal liability; provided that the  Trustee may take  any
  other action deemed proper  by the Trustee  that is not  inconsistent with
  such direction.   Prior to taking any action hereunder,  the Trustee shall be
  entitled to  indemnification satisfactory to it  in its sole discretion
  against all losses and expenses caused by taking or not taking such action.

                   SECTION 6.06.   Limitation on  Suits.  No  Holder of any
  Securities shall have  any right  to institute any  proceeding, judicial or
  otherwise, with respect  to this Indenture, or  for the appointment of a
  receiver or a trustee, or for any other remedy hereunder, unless:

                   (i)      such Holder has previously  given to the Trustee
           written notice of a continuing Event of Default with respect to the
           Securities;





                                       53
<PAGE>   61
                   (ii)     the Holders of  at least 25% in aggregate principal
           amount  at Stated Maturity of the Securities then  outstanding  have
           made  written request,  and  such Holder  or  Holders have  offered
           reasonable indemnity, to the Trustee to institute such proceeding as
           trustee; and

                   (iii)    the Trustee  has failed to institute such
           proceeding, and has not  received from the Holders  of  a majority
           in  aggregate principal  amount at  Stated  Maturity of  the
           Securities then outstanding a direction inconsistent with such
           request, within 60  days after such notice, request and offer.

                   A Holder may not use this Indenture to  prejudice the rights
  of another Holder  or to obtain a preference or priority over another Holder.

                   SECTION 6.07.   Rights of Holders to Receive Payment.
  Notwithstanding any  other provision of this Indenture, the  right of any
  Holder to receive payment of  principal of and  interest on the  Securities
  held by such  Holder, on or after the  respective due dates expressed in the
  Securities, or  to bring suit for the  enforcement of  any such  payment on
  or  after such respective  dates, shall  not be impaired  or affected without
  the consent of such Holder.

                   SECTION  6.08.   Collection Suit  by Trustee.   If an  Event
  of  Default specified  in Section 6.01(a)  or (b) occurs and is continuing,
  the Trustee  may recover judgment in its own  name and as trustee of an
  express trust  against the Company for the whole amount then  due and owing
  (together with  interest on any unpaid interest to the extent lawful) and the
  amounts provided for in Section 7.07.

                   SECTION 6.09.    Trustee  May File  Proofs  of Claim.    The
  Trustee  shall be  entitled  and empowered, without  regard to whether the
  Trustee or any Holder  shall have made any  demand or performed  any other
  act pursuant  to the provisions  of this  Article and  without regard to
  whether  the principal  of the Securities shall then be due and payable as
  therein expressed or by declaration or  otherwise, by intervention in  any
  proceedings  relative  to  the Company  or any  Obligor upon  the Securities,
  or  to the  creditors or Property or  assets of  the Company, any Guarantor
  or any  other Obligor or  otherwise, to  take any  and all actions authorized
  under the  Trust Indenture Act  in order  to have  claims of the Holders  and
  the  Trustee allowed in  any  such  proceeding.   In  particular,  the
  Trustee shall  be  entitled  and empowered  in  such instances:

                   (a)      to file and prove a  claim or claims for the whole
  amount of  principal (and premium, if any), interest and  any other amounts
  owing and unpaid in  respect of the Securities, and to file such other papers
  or documents as may  be necessary or advisable  in order to have  the claims
  of the  Trustee (including all amounts owing  to the Trustee  and each
  predecessor Trustee  pursuant to Section 7.07  hereof) and of  the Holders
  allowed in any  judicial proceedings relative to the Company  or other
  obligor upon the Securities,  or to the creditors or property of the Company,
  any Guarantor, or any such other Obligor,





                                       54
<PAGE>   62





                   (b)      unless  prohibited  by applicable  law  and
  regulations,  to  vote on  behalf  of the Holders of the  Securities in any
  election  of a trustee or a  standby trustee in arrangement,  reorganization,
  liquidation  or  other  bankruptcy  or  insolvency  proceedings  or  Person
  performing  similar  functions  in comparable proceedings, and

                   (c)      to collect and  receive any moneys or other
  Property or assets payable or deliverable on any such claims,  and to
  distribute all amounts received with respect  to the claims of the Holders
  and of the Trustee on their behalf; and  any trustee, receiver, or
  liquidator, custodian or other similar official  is hereby authorized by
  each of the Holders to make payments  to the Trustee, and,  in the event that
  the Trustee shall  consent to the making  of payments directly to the
  Holders, to pay  to the Trustee such amounts as shall be  sufficient to cover
  all amounts  owing to  the Trustee  and each  predecessor Trustee pursuant
  to Section 7.07.

                   Nothing herein  contained shall be deemed to  authorize the
  Trustee to authorize or consent to or vote for  or accept or adopt on behalf
  of any Holder any plan of reorganization, arrangement, adjustment or
  composition  affecting the Securities or the rights  of any Holder thereof,
  or to authorize the Trustee to vote in respect of the  claim of any Holder in
  any such proceeding except, as aforesaid, to vote  for the election of a
  trustee in bankruptcy or similar person.

                   In  any  proceedings  brought  by  the  Trustee  (and  also
  any  proceedings  involving  the interpretation  of any provision of this
  Indenture to which the Trustee  shall be a party), the Trustee shall be  held
  to represent all the Holders of the  Securities, and it shall not be
  necessary to make any Holders of the Securities parties to any such
  proceedings.

                   SECTION 6.10.  Priorities.   If the Trustee  collects any
  money or  property pursuant to this Article 6, it shall pay out the money or
  property in the following order:

                   FIRST:  to the Trustee for amounts due under Section 7.07;

                   SECOND:   to Holders for amounts due and unpaid on the
           Securities for principal and interest, ratably, without preference
           or  priority of any kind, according to the amounts  due and payable
           on the Securities for principal (premium, if any) and interest,
           respectively; and

                   THIRD:   to the  Company or the  Guarantors or  to such
           other  party as  a court  of competent jurisdiction shall direct.

                   The  Trustee may fix a  record date and  payment date  for
  any payment to  Holders pursuant to this Section.   At  least 15 days before
  such  record date,  the Company  shall mail  to each  Holder and  the Trustee
  a notice that states  the record date, the payment date  and amount to be
  paid.  The Trustee  may mail such notice in the name and at the expense of
  the Company.

                   SECTION 6.11.   Undertaking  for Costs.   In  any suit  for
  the  enforcement of  any right  or remedy under this Indenture or in any suit
  against the Trustee for any action taken or





                                       55
<PAGE>   63





  omitted  by it as Trustee, a court in its  discretion may require the filing
  by any party litigant in the suit of  an undertaking to pay the costs of the
  suit, and the court in its discretion  may assess reasonable costs, including
  reasonable attorneys' fees, against any party litigant  in the suit, having
  due regard  to the merits and good faith of  the claims or  defenses made by
  the party litigant.   This Section does not apply  to a suit by  the Trustee,
  a suit  by a  Holder pursuant  to Section  6.07 or  a suit  by  Holders of
  more than  10% in principal amount at Stated Maturity of the Securities.

                   SECTION  6.12   Restoration  of  Rights  and  Remedies.   If
  the  Trustee  or any  Holder  of Securities has  instituted any  proceeding
  to enforce  any  right or  remedy under  this Indenture  and  such proceeding
  has been discontinued or abandoned  for any reason, or has been determined
  adversely to the  Trustee or to such  Holder, then and in every such case the
  Company, the Trustee and the  Holders shall, subject to any determination in
  such proceeding, be  restored severally and respectively to their former
  positions  hereunder, and  thereafter all  rights and  remedies of  the
  Trustee  and the  Holders shall  continue  as though  no such proceeding has
  been instituted.

                   SECTION 6.13  Rights and  Remedies Cumulative.  Except as
  otherwise provided in  Section 2.08 hereof, no  right or remedy conferred
  herein, upon or reserved to the Trustee or  to the Holders is intended to be
  exclusive of any other  right or remedy, and  every right and remedy shall,
  to the extent  permitted by law, be cumulative and in addition to every other
  right and remedy  given hereunder or now or hereafter existing at law  or in
  equity or otherwise.  The assertion  or employment of any right  or remedy
  hereunder, or otherwise, shall not prevent the concurrent assertion or
  employment of any other appropriate right or remedy.

                   SECTION 6.14   Delay or Omission Not  Waiver.  No delay or
  omission of the  Trustee or of any Holder of any  Security to exercise any
  right or remedy accruing  upon any Event of Default shall  impair any such
  right or  remedy or constitute a waiver of  any such Event of Default  or an
  acquiescence therein.  Every right and  remedy given by this  Article 6 or by
  law to the Trustee  or to the Holders may  be exercised from time to time,
  and as often as may be deemed expedient, by the Trustee or by the Holders, as
  the case may be.


                                   ARTICLE 7

                                    Trustee

                   SECTION 7.01.  Duties of Trustee.

                   (a)      If an  Event of Default  has occurred and is
  continuing, the Trustee  shall exercise the  rights and  powers vested in  it
  by this  Indenture and  use the same  degree of care and  skill in their
  exercise as a prudent  Person would exercise  or use  under the circumstances
  in  the conduct of such  Person's own affairs.

                   (b)      Except during the continuance of an Event of
  Default:





                                       56
<PAGE>   64
                   (1) the  Trustee undertakes to perform  such duties  and
           only such duties  as are specifically set forth in this Indenture
           and no implied  covenants or obligations shall be read into this
           Indenture against the Trustee; and

                   (2) in the absence  of bad faith on  its part, the  Trustee
           may  conclusively rely, as to  the truth  of the statements and  the
           correctness of the opinions  expressed therein, upon certificates or
           opinions furnished to the Trustee and conforming to the
           requirements of this Indenture.  However, the Trustee shall examine
           the  certificates and opinions to determine  whether or not they
           conform  to the requirements of this Indenture.

                   (c)      The Trustee may not be relieved from liability for
  its own  negligent action, its own negligent failure to act or its own
  willful misconduct, except that:

                   (1) this subsection does not limit the effect of subsection
                       (b) of this Section;

                   (2) the  Trustee shall not be liable for any  error of
           judgment made in good faith by a Trust Officer unless it is proved
           that the Trustee was negligent in ascertaining the pertinent facts;
           and

                   (3) the Trustee shall not be liable with  respect to any
           action it takes or  omits to take in good faith in accordance with a
           direction received by it pursuant to Section 6.05.

                   (d)      Every provision of  this Indenture that in any way
  relates  to the Trustee is subject to subsections (a), (b) and (c) of this
  Section.

                   (e)      The Trustee shall not  be liable for interest on
  any money received by it  except as the Trustee may agree in writing with the
  Company.

                   (f)      Money held in trust by the Trustee need not  be
  segregated from other funds except to the extent required by law.

                   (g)      No provision of  this Indenture shall require  the
  Trustee to expend or  risk its own funds or otherwise  incur financial
  liability in  the performance  of any of  its duties hereunder  or in  the
  exercise  of any of its  rights or powers,  if it shall  have reasonable
  grounds to believe  that repayment of such funds or adequate indemnity
  against such risk or liability is not reasonably assured to it.

                   (h)      Every provision  of this Indenture relating to the
  conduct or affecting the liability of or  affording protection to the
  Trustee shall  be subject to  the provisions  of this  Section and to  the
  provisions of the Trust Indenture Act.

                   SECTION 7.02.  Rights of Trustee.





                                       57
<PAGE>   65





                   (a)      Subject  to the  provisions of Section 7.01(a)
  hereof, the  Trustee may  rely on any document believed by  it to be genuine
  and to have been signed or presented by the  proper Person.  The Trustee need
  not investigate any fact or matter stated in the document.

                   (b)      Before  the Trustee  acts  or  refrains from
  acting,  it  may require  an  Officers' Certificate or an  Opinion of
  Counsel.  The  Trustee shall not be  liable for any action it takes or  omits
  to take in good faith in reliance on the Officers' Certificate or Opinion of
  Counsel.

                   (c)      The  Trustee may act through  agents and shall not
  be responsible for the misconduct or negligence of any agent appointed with
  due care.

                   (d)      The Trustee  shall not be  liable for any  action
  it takes or  omits to take  in good faith  which  it believes  to  be
  authorized  or  within  its rights  or  powers; provided,  however,  that the
  Trustee's conduct does not constitute willful misconduct or negligence.

                   (e)      The Trustee  may consult  with counsel,  and the
  advice  or opinion  of counsel  with respect  to  legal  matters  relating
  to this  Indenture  and  the  Securities shall  be  full  and  complete
  authorization and  protection from  liability  in respect  to  any action
  taken, omitted  or suffered  by  it hereunder in good faith and in accordance
  with the advice or opinion of such counsel.

                   (f)      Prior  to the occurrence  of an Event  of Default
  hereunder and after  the curing or waiving of all Events of Default, the
  Trustee shall not be  bound to make any investigation into the facts  or
  matters  stated  in  any  resolution,  Officer's  Certificate,  or  other
  certificate,  statement,  instrument, opinion,  report,  notice,  request,
  consent,  order,  approval,  appraisal,  bond,  debenture,  note, coupon,
  security, or other paper or  document unless requested in writing to  do so
  by the Holders of not less  than a majority  in aggregate  principal amount
  of the  Securities  then  outstanding; provided  that if  the payment within
  a reasonable time  to the Trustee of the costs, expenses or  liabilities
  likely to be incurred by it  in the making of such investigation is, in the
  opinion of the Trustee, not reasonably assured  to the Trustee by the
  security afforded to  it by  the terms  of this  Indenture, the  Trustee may
  require  reasonable indemnity against such  expenses or liabilities  as a
  condition to  proceeding; the  reasonable expenses  of every  such
  examination shall  be paid by the  Company or, if advanced by the Trustee,
  shall  be repaid by the Company upon demand.

                   (g)      The Trustee shall  not be  required to  give any
  bond or  surety in  respect of  the performance of its powers and duties
  hereunder.

                   (h)      The Trustee  shall not be  bound to  ascertain or
  inquire as to  the performance  or observance of  any covenants, conditions,
  or  agreements on the  part of the Company,  except as otherwise  set forth
  herein, but the Trustee may require of the Company full information and
  advice as  to the performance of the  covenants, conditions  and agreements
  contained  herein and shall be  entitled in  connection herewith to examine
  the books, records and premises of the Company.





                                       58
<PAGE>   66
                   (i)      The permissive rights of the Trustee to do things
  enumerated in this Indenture shall not be construed as a duty.

                   (j)      Except for (i) a default under Section 6.01(a) or
  (b), or  (ii) any other event of which the Trustee has "actual knowledge"
  and which  event, with the giving of notice or the passage of time or both,
  would  constitute an Event of Default under this  Indenture, the Trustee
  shall not  be deemed to have notice of any Default or Event of Default
  unless specifically  notified in writing of such event by the Company or
  the  Holders of not less than 25% in aggregate principal amount at
  Stated Maturity of the Securities then outstanding; provided that the
  Trustee  shall comply with the "automatic stay" provisions contained in
  the  U.S. bankruptcy laws, if applicable; and as used herein, the term
  "actual knowledge" means the actual fact or statement of knowing by  a
  Responsible Officer, without any duty to  make any investigation with regard
  thereto.

                   SECTION  7.03.  Individual Rights of Trustee.  The Trustee
  in  its individual or any other capacity may become the owner or pledgee
  of  Securities and may otherwise deal with the Company or its Affiliates
  with the same rights it would have if it were not Trustee.  Any Paying
  Agent, Registrar,  co-registrar or co-paying agent may do the same with
  like rights.  However, the Trustee must comply with Sections 7.10 and
  7.11.

                   SECTION  7.04. Trustee's Disclaimer. The Trustee shall not
  be responsible for and makes no representation  as to the validity or
  adequacy  of this Indenture or the Securities, it shall not be
  accountable for the Company's  use of the proceeds from the Securities, and
  it shall not be responsible for any statement of the Company in this
  Indenture or in any document issued in connection with the sale of the
  Securities or in the Securities other than the Trustee's certificate of
  authentication.

                   SECTION 7.05.  Notice of Defaults.   If a Default occurs and
  is continuing and if it is known to the Trustee,  the Trustee shall mail to
  each  Holder notice of the Default within 90 days after it occurs. Except
  in the case of  a Default in payment of principal of (or premium, if any) or
  interest on  any Security (including payments pursuant to the mandatory
  repurchase provisions  of such Security, if any), the Trustee may withhold
  the notice if and so long as the Trustee in good faith determines that
  withholding the notice is in the interests of Holders.

                   SECTION  7.06.  Reports by Trustee to Holders.   As
  promptly as practicable after May 15 beginning with the May 15 following
  the date of this Indenture, and in any event prior to August 15 in each
  year, the Trustee shall mail to each Holder a brief report dated as of
  such date that complies with TIA Section 313(a) if and to  the extent
 required by TIA  Section 313(a). The Trustee also shall comply with TIA
  Sections 313(b) and 313(c).

                   A copy of each report at the time of its mailing to
  Holders shall be filed with the Commission and each stock exchange (if
  any) on which the Securities are listed. The Company agrees  to notify
 promptly the Trustee whenever the Securities become listed on any stock
  exchange and of any delisting thereof.





                                       59
<PAGE>   67
                   SECTION 7.07.   Compensation and Indemnity.   The  Company
  shall pay  to the Trustee  promptly upon request from time  to time the
  compensation for its services as agreed to by the  Trustee and the Company.
  The  Trustee's compensation shall not be limited by any law on compensation
  of a trustee of an express trust.  The  Company shall  reimburse the  Trustee
  promptly  upon  request for  all reasonable  out-of-pocket expenses incurred
  or made by  it, including  costs of  collection, in  addition to  the
  compensation for  its services.  Such  expenses shall  include  the
  reasonable  compensation and  expenses, disbursements  and advances  of the
  Trustee's agents, counsel, accountants and  experts.  The Company shall
  indemnify  the Trustee against any and all loss, liability or reasonable
  expense  (including reasonable attorneys' fees) incurred  by it in connection
  with  the acceptance  and administration  of this  trust  and  the
  performance  of its  duties hereunder.   The Trustee shall  notify the
  Company promptly  of any  claim for which  it may  seek indemnity.   Failure
  by  the Trustee  to so notify the Company  shall not relieve  the Company of
  its obligations hereunder.   The Company shall  defend the claim  and the
  Trustee may have separate  counsel and  the Company shall  pay the  fees and
  expenses  of  such counsel.    The Company  need  not  reimburse any  expense
  or indemnify  against  any loss, liability  or expense incurred by the
  Trustee through the Trustee's  own willful misconduct, negligence or bad
  faith.  The Company  need not pay for any  settlement made by the Trustee
  without the Company's  consent, such consent not to be unreasonably withheld.

                   To secure the Company's  payment obligations  in this
  Section, the  Trustee shall have a  Lien prior  to the  Securities on  all
  money  or property  held or  collected by  the Trustee  other than  money or
  property held in trust to pay principal of and interest on particular
  Securities.

                   The Company's  payment obligations  pursuant to  this
  Section  shall survive the  discharge of this  Indenture.  When  the Trustee
  incurs expenses  after the  occurrence of  a Default specified  in Section
  6.01(g)  or  (h)  with  respect  to  the  Company,  the  expenses  are
  intended  to  constitute  expenses  of administration under any applicable
  bankruptcy laws.

                   SECTION 7.08.  Replacement  of Trustee.  The  Trustee may
  resign  at any time by  so notifying the Company.  The Holders of a  majority
  in principal amount at  Stated Maturity of the Securities  may remove the
  Trustee by so notifying the Trustee and may appoint a successor Trustee.  If
  at any time:

                            (i)     the Trustee shall fail  to comply with
           Section 310(b) of the Trust  Indenture Act after written request
           thereof by the Company  or by any Holder who has been a bona  fide
           Holder of a Security for at least six  months, unless the Trustees
           duty to resign is  stayed in accordance with the provisions of TIA
           Section 310(b); or

                            (ii)    the  Trustee shall cease to  be eligible
           under Section 7.10  hereof and shall fail to resign after written
           request therefor by the Company or by any Holder; or

                            (iii)   the Trustee shall become incapable of
           acting or a decree or order for relief by a court having
           jurisdiction  in the premises shall have  been entered in respect of
           the  Trustee in an involuntary case  under the United States
           bankruptcy laws, as  now or hereafter constituted, or any other
           applicable federal or state bankruptcy, insolvency or





                                       60
<PAGE>   68
           similar law,  or a decree or order by  a court having jurisdiction
           in the premises shall have been entered for  the appointment  of a
           receiver, custodian,  liquidator, assignee,  trustee, sequestrator
           (or  other similar  official) of the  Trustee or  of its Property
           and assets or affairs, or  any public  officer  shall take  charge
           or  control  of the  Trustee  or of  its Property and  assets or
           affairs for the  purpose of rehabilitation,  conservation,
           winding-up or liquidation; or

                            (iv)    the  Trustee  shall  commence  a  voluntary
           case  under  the  United  States bankruptcy  laws,  as  now  or
           hereafter  constituted,  or  any  other  applicable  federal  or
           state bankruptcy, insolvency or similar law  or shall consent to the
           appointment of or  taking possession by a receiver, custodian,
           liquidator, assignee, trustee,  sequestrator (or other similar
           official) of the Trustee or  of its Property  and assets or
           affairs, or  shall make an  assignment for the  benefit of
           creditors,  or shall admit in writing its inability to  pay its
           debts generally as they become due, or shall take corporate action
           in furtherance of any such action,

  then, in any  such case,  (i) the Company by  a Board Resolution  may remove
  the  Trustee with respect to  the Securities, or (ii) subject to  Section
  6.11 hereof, any Holder who has been  a bona fide Holder of a Note for at
  least six months may,  on behalf of such  Holder and all others  similarly
  situated, petition any  court of competent  jurisdiction for the  removal of
  the Trustee  and the  appointment of  a successor Trustee  for the
  Securities.

                   If  the Trustee  resigns, is  removed  by the  Company or
  by  the Holders  of a  majority  in principal amount at Stated  Maturity of
  the Securities  and such Holders  do not reasonably promptly  appoint a
  successor  Trustee, or if a vacancy exists in  the office of Trustee  for any
  reason (the Trustee in such event being referred to herein as the retiring
  Trustee), the Company shall promptly appoint a successor Trustee.

                   A successor  Trustee shall deliver  a written acceptance  of
  its appointment to  the retiring Trustee  and to  the Company.   Thereupon
  the resignation  or removal  of the  retiring Trustee  shall  become
  effective, and the  successor Trustee shall have all  the rights, powers and
  duties  of the Trustee under this Indenture.   The successor  Trustee shall
  mail  a notice of  its succession to Holders.   The retiring Trustee shall
  promptly  transfer all  property held by  it as  Trustee to  the successor
  Trustee, subject to  the Lien provided for in Section 7.07.

                   If  a successor  Trustee  does not  take office  within  60
  days  after  the  retiring Trustee resigns or is  removed, the retiring
  Trustee or  the Holders of 10% in  principal amount at Stated Maturity of the
  Securities may petition any court of competent jurisdiction for the
  appointment of a successor Trustee.

                   If  the Trustee  fails to  comply with Section  7.10, any
  Holder may  petition any  court of competent jurisdiction for the removal of
  the Trustee and the appointment of a successor Trustee.





                                       61
<PAGE>   69
                   Notwithstanding  the replacement  of  the  Trustee  pursuant
  to  this  Section, the  Company's obligations under Section 7.07 shall
  continue for the benefit of the retiring Trustee.

                   SECTION 7.09.   Successor Trustee by  Merger.   If the
  Trustee  consolidates with,  merges or converts  into, or  transfers all  or
  substantially all  its corporate  trust business  or assets  to, another
  corporation or banking  association, the resulting,  surviving or  transferee
  corporation  without any  further act shall be the successor Trustee.

                   In case  at the time such  successor or successors by
  merger, conversion  or consolidation to the Trustee  shall succeed  to the
  trusts created by this  Indenture any  of the  Securities shall  have been
  authenticated  but  not  delivered,   any  such  successor  to  the   Trustee
  may  adopt  the  certificate  of authentication of any predecessor trustee,
  and  deliver such Securities so authenticated; and in case at  that time any
  of the  Securities shall not have  been authenticated, any  successor to the
  Trustee  may authenticate such Securities  either in  the name  of any
  predecessor hereunder  or in the name  of the  successor to  the Trustee; and
  in all  such cases  such certificates  shall have  the full  force which it
  is  anywhere in  the Securities or in this Indenture provided that the
  certificate of the Trustee shall have.

                   SECTION 7.10.   Eligibility; Disqualification.   The Trustee
  shall  at all times  satisfy the requirements of  TIA Section  310(a).   The
  Trustee shall  have a  combined capital  and surplus  of at  least
  $100,000,000 as set forth in its  most recent published annual report of
  condition.   The Trustee shall comply with TIA  Section 310(b); provided,
  however, that there  shall be excluded from the  operation of TIA Section
  310(b)(1)  any  indenture  or  indentures  under  which  other  securities
  or  certificates  of  interest  or participation in  other securities of the
  Company are outstanding  if the requirements for  such exclusion set forth in
  TIA Section 310(b)(1) are met.

                   SECTION 7.11.   Preferential Collection of Claims Against
  Company.   The Trustee shall comply with TIA Section 311(a), excluding any
  creditor relationship  listed in TIA Section 311(b).   A Trustee who has
  resigned or been removed shall be subject to TIA Section 311(a) to the extent
  indicated therein.


                                   ARTICLE 8

                           Satisfaction and Discharge

                   SECTION 8.01   Satisfaction  and Discharge.   This
  Indenture shall  upon the  request of  the Company cease to be of further
  effect (except as to  surviving rights of registration of transfer or
  exchange of Securities  herein expressly provided for,  the Company's
  obligations under  Sections 7.07  and 8.04 hereof, and  the Company's,  the
  Trustee's  and the  Paying Agent s  obligations under  Section 8.03  hereof)
  and the Trustee, at  the expense  of the  Company, shall  execute proper
  instruments acknowledging  satisfaction  and discharge of this Indenture when

                   (a)      either





                                       62
<PAGE>   70
                            (i)     all  Securities  therefore  authenticated
           and  delivered  (other  than  (A) Securities which have been
           destroyed, lost or stolen  and which have been replaced or paid as
           provided in Section 2.08  and (B)  Securities for  whose payment
           money  has been  deposited in  trust with  the Trustee or  any
           Paying Agent and  thereafter paid to the  Company or discharged from
           such trust) have been delivered to the Trustee for cancellation; or

                            (ii)    all  such   Securities  not  theretofore
           delivered  to   the  Trustee   for cancellation

                             (A)    have become due and payable, or

                             (B)    will become due and payable at their Stated 
                   Maturity within one year, or

                             (C)     are  to  be  called  for  redemption
                   within  one  year  under   irrevocable arrangements
                   satisfactory to  the Trustee  for the  giving of  notice  of
                   redemption  by the Trustee in the name, and at the expense,
                   of the Company,

           and the Company, in the case of  clause (A), (B) or (C) above, has
           irrevocably deposited  or caused to be deposited with  the Trustee
           as trust  funds in trust  for such  purpose money  or U.S.
           Government Obligations in an amount  sufficient (as certified by  an
           independent public accountant  designated by the  Company)  to  pay
           and  discharge  the  entire  indebtedness of  such  Securities  not
           theretofore delivered to the Trustee  for cancellation, for
           principal (and  premium, if any, on) and  interest, if any, to the
           date of such deposit (in  the case of Securities which have become
           due and payable) or the Stated Maturity or Redemption Date, as the
           case may be;

                   (b)      the Company  has paid  or caused  to  be paid  all
  other  sums then  due and  payable hereunder by the Company;

                   (c)      no Default or  Event of Default  with respect to
  the Securities shall  have occurred and be continuing on the date of such
  deposit and after giving effect to such deposit; and

                   (d)      the Company has delivered to the  Trustee an
  Officers' Certificate and an Opinion  of Counsel, each  stating that  all
  conditions  precedent herein  provided for  relating to  the satisfaction
  and discharge of this Indenture have been complied with.

                   Notwithstanding the satisfaction  and discharge of this
  Indenture, the  Company s obligations in Sections 2.03, 2.04,  2.06, 2.08,
  2.11, 7.07,  7.08, 8.02,  8.03 and 8.04,  and the  Trustee s and  Paying
  Agent s  obligations  in  Section  8.03  shall  survive  until  the
  Securities  are  no  longer  outstanding.  Thereafter, only  the Company s
  obligations in  Sections 7.07,  8.03 and  8.04 and the  Trustee s and  Paying
  Agent s obligations in Section 8.03 shall survive.





                                       63
<PAGE>   71
                   In  order to have money  available on a  payment date  to
  pay principal (and  premium, if any, on) or  interest on  the Securities, the
  U.S. Government  Obligations shall be  payable as  to principal  (and
  premium,  if any) or  interest at  least one Business Day  before such
  payment date in  such amounts  as will provide the necessary money.  U.S.
  Government Obligations shall not be callable at the issuer s option.

                   SECTION 8.02  Application of Trust  Money.  All money
  deposited with the Trustee pursuant  to Section 8.01  shall be  held in
  trust and,  at the  written direction  of the  Company, be invested prior  to
  maturity in U.S. Government  Obligations, and applied by the Trustee  in
  accordance with the provisions of  the Securities  and this Indenture, to the
  payment, either directly or through any  Paying Agent as the Trustee may
  determine, to  the Persons  entitled thereto,  of the  principal (and
  premium, if  any) and  interest for  the payment of which money has been
  deposited with the Trustee;  but such money need not be segregated  from
  other funds except to the extent required by law.

                   SECTION 8.03  Repayment to the Company.

                   The Trustee and the Paying  Agent shall promptly pay to the
  Company upon written request any excess money or securities held by them at
  any time.

                   The Trustee and  the Paying Agent  shall pay  to the Company
  upon written request  any money held by them  for the payment of principal
  or interest that  remains unclaimed for two  years after the  date upon
  which such payment shall have become due; provided  that the  Company shall
  have either caused notice of such payment  to  be mailed  to each
  Securityholder  entitled thereto  no less  than 30  days prior  to  such
  repayment  or within  such period  shall have published  such notice  in a
  financial newspaper  of widespread circulation published in The City of  New
  York, including, without limitation, The Wall Street Journal.   After payment
  to the  Company, Holders  entitled to  the money  must  look to  the Company
  for payment  as  general creditors  unless an  applicable abandoned property
  law designates another Person,  and all  liability of the Trustee and such
  Paying Agent with respect to such money shall cease.

                   SECTION 8.04  Reinstatement.

                   If the Trustee or  Paying Agent is unable  to apply any
  money  or U.S. Government Obligations in accordance with Section  8.01 by
  reason of  any legal proceeding or  by reason of  any order or judgment  of
  any court  of governmental  authority enjoining,  restraining or otherwise
  prohibiting  such application,  the Company s and  Guarantors   obligations
  under  this Indenture,  the Securities  and  the Guarantees  shall  be
  revived and reinstated  as though  no deposit has  occurred pursuant  to
  Section  8.01 until  such time as  the Trustee or  Paying Agent is  permitted
  to apply  all such money  or U.S. Government  Obligations in  accordance with
  Section  8.02; provided, however, that if the  Company or the Guarantors have
  made any payment of interest on or  principal of  any Securities because  of
  the  reinstatement of their  Obligations, the  Company or  such Guarantors
  shall be subrogated to the rights of the Holders of such Securities to
  receive





                                       64
<PAGE>   72
  such payment from the money or U.S. Government Obligations held by the
  Trustee or Paying Agent.


                                   ARTICLE 9

                                   Defeasance

                   SECTION 9.01  Company's Option to  Effect Defeasance or
  Covenant Defeasance.   The Company may elect, at its option,  at any time,
  to have Section 9.02  or Section 9.03  hereof applied to  the outstanding
  Securities (in whole and not in part) upon  compliance with the conditions
  set forth below  in this Article 9, such election to be evidenced by a Board
  Resolution delivered to the Trustee.

                   SECTION 9.02 Defeasance  and Discharge.   Upon the Company's
  exercise of its option to  have this Section  9.02 applied  to the
  outstanding  Securities (in  whole and  not in  part), the Company  shall be
  deemed to  have been  discharged from  its Obligations  with respect  to such
  Securities as  provided in  this Section 9.02 on  and after the date  on
  which the  conditions set forth  in Section 9.04 hereof are  satisfied
  (hereinafter called "Defeasance").   For this  purpose, Defeasance  means
  that the  Company shall be deemed  to have paid  and discharged  the entire
  indebtedness represented  by such  Securities and the  Company and  the
  Guarantors shall be  deemed to  have satisfied  all of  their other
  obligations under  such Securities,  this Indenture  and  the  Guarantees
  (and  the Trustee,  at  the expense  of  the  Company,  shall  execute proper
  instruments  acknowledging the same), subject to the following which  shall
  survive until otherwise terminated or discharged hereunder:

                   (a)      the  rights of  Holders of  such Securities  to
  receive, solely  from the  trust fund described in Section  9.04 hereof  and
  as more  fully set forth  in Section 9.04,  payments in respect of  the
  principal of and any premium and interest on such Securities when payments
  are due,

                   (b)      the Company's obligations with respect to such
  Securities under Sections  2.06, 2.08, 2.10, 4.15, 4.16 and 4.17 hereof,

                   (c)      the  rights,  powers,  trusts,  duties  and
  immunities  of  the  Trustee  under  this Indenture,

                   (d)      Article 3 hereof, and

                   (e)      this Article 9.

                   Subject  to compliance with this Article 9, the Company may
  exercise its option to have this Section 9.02 applied  to the outstanding
  Securities  notwithstanding the prior exercise of its option  to have Section
  9.03 hereof applied to such Securities.





                                       65
<PAGE>   73
                   SECTION 9.03  Covenant  Defeasance.  Upon the  Company's
  exercise of its  option to have this Section 9.03  applied to  the
  outstanding  Securities  (in whole  and not  in part),  (i) the  Company and
  the Guarantors shall  be released from  their respective obligations  under
  Sections 5.01  and 5.02, Sections  4.02 through 4.14, inclusive, Sections
  4.18, 4.19 and 4.21 and any  covenant added to this Indenture subsequent  to
  the Issue Date pursuant  to Section 10.01 hereof,  and (ii) the  occurrence
  of  any event specified in  Section 6.01(c)  or 6.01(d)  hereof,  with
  respect  to  any of  Section  5.01 and  5.02,  Sections 4.03  through  4.14,
  inclusive, Sections 4.18,  4.19 and 4.21,  and any  covenant added  to this
  Indenture  subsequent to the  Issue Date pursuant to  Section 10.01 hereof,
  shall be  deemed not to be  or result in an Event of Default,  in each case
  with  respect to such  Securities as provided  in this  Section 9.03  on and
  after  the date on  which the conditions set  forth in Section  9.04 hereof
  are  satisfied (hereinafter called  "Covenant Defeasance").   For this
  purpose, Covenant Defeasance means that,  with respect to such Securities,
  the Company and the Guarantors may omit  to comply with and shall have no
  liability in respect of any term, condition or limitation set forth in any
  such specified Section (to the extent so specified in the case of Section
  6.01(c) and  6.01(d) hereof), whether directly or indirectly by  reason of
  any reference elsewhere herein to  any such Section or by  reason of  any
  reference  in any  such Section  to any  other provisions  herein or  in any
  other document;  but the remainder of this Indenture, the Guarantees and such
  Securities shall be unaffected thereby.

                   SECTION 9.04  Conditions  to Defeasance  or Covenant
  Defeasance.   The following shall be  the conditions to the application of
  Section 9.03 or Section 9.04 hereof to the outstanding Securities:

                   (a)      The  Company shall  irrevocably have  deposited or
  caused to  be deposited  with the Trustee as  trust funds in  trust for the
  purpose of making  the following payments,  specifically pledged  as security
  for, and dedicated solely to the benefits of the Holders of such Securities,
  (i) money in an amount, or (ii) U.S. Government Obligations which  through
  the scheduled payment of principal and interest in  respect thereof  in
  accordance with their terms  will provide, not later than  one Business Day
  before the due date of any payment, money in an amount, or (iii) a
  combination thereof, in each case sufficient, in  the opinion of a nationally
  recognized  firm of  independent public  accountants expressed in a  written
  certification  thereof delivered to the Trustee, to pay and  discharge the
  principal of (premium,  if any on) and any  installment of interest  on such
  Securities on  the Stated Maturity  thereof, in  accordance with the terms
  of this Indenture and such Securities.

                   (b)      In the event  of an election  to have Section  9.02
  hereof  apply to the  outstanding Securities,  the Company  shall have
  delivered to  the  Trustee  an Opinion  of Counsel  stating that  (i) the
  Company  has received from,  or there has  been published  by, the Internal
  Revenue Service  a ruling  or (ii) since the date of  this Indenture, there
  has been a change  in the applicable United States federal income tax law, in
  either case (i) or  (ii) to the effect  that, and based thereon  such opinion
  shall  confirm that, the Holders of such Securities will not recognize gain
  or loss for  United States federal income tax purposes as a result of the
  deposit,  Defeasance and discharge to  be effected with respect  to such
  Securities  and will  be subject to United States federal  income tax in the
  same amount,  in the same manner and at the same  times as would be the case
  if such deposit, Defeasance and discharge were not to occur.





                                       66
<PAGE>   74
                   (c)      In the  event of an  election to have  Section 9.03
  hereof  apply to  the outstanding Securities,  the Company shall  have
  delivered  to the  Trustee an  Opinion of Counsel  to the effect  that the
  Holders of such Securities will not recognize gain or loss for United States
  federal income  tax purposes as a result of  the deposit and  Covenant
  Defeasance to  be effected  with respect to  such Securities  and will  be
  subject to United States federal  income tax in the same amount,  in the same
  manner and at the same  times as would be the case if such deposit, Covenant
  Defeasance and discharge were not to occur.

                   (d)      No Default or Event of Default with respect to the
  outstanding Securities shall  have occurred and be continuing at the time of
  such deposit  after giving effect thereto or and no  Default or Event of
  Default under  Section 6.01(g) or 6.01(h) shall have occurred at any time on
  or prior  to the 91st day after the date of  such deposit and be continuing
  on  such 91st day (it  being understood that this  condition shall not be
  deemed satisfied until after such 91st day).

                   (e)      Such  Defeasance or  Covenant  Defeasance  shall
  not  cause  the  Trustee to  have  a conflicting interest within the  meaning
  of the Trust  Indenture Act (assuming  for the purpose of  this clause (e)
  that all Securities are in default within the meaning of such Act).

                   (f)      Such Defeasance or Covenant Defeasance shall not
  result in a breach  or violation of, or constitute a default under, any other
  agreement or instrument to which  the Company or the Guarantor  is a party or
  by which it is bound.

                   (g)      Such Defeasance or  Covenant Defeasance shall  not
  result in  the trust arising  from such deposit  constituting an investment
  company within the  meaning of the Investment  Company Act of 1940, as
  amended, unless such trust shall be registered under such Act or exempt from
  registration thereunder.

                   (h)      The Company  shall have  delivered to  the Trustee
  an Officers'  Certificate and  an Opinion of  Counsel, each stating  that all
  conditions  precedent with respect to such  Defeasance or Covenant Defeasance
  have been complied with.

                   SECTION  9.05    Deposited  Money and  U.S.  Government
  Obligations  to  be  Held  in Trust; Miscellaneous  Provisions.    Subject to
  Section  9.06 hereof,  all  money  and  U.S. Government  Obligations
  (including the proceeds thereof) deposited with  the Trustee pursuant to
  Section 9.04 hereof in respect of  the outstanding Securities shall be  held
  in trust and  applied by the  Trustee, in accordance with  the provisions of
  such Securities  and this Indenture, to  the payment, either directly  or
  through any  such Paying  Agent as the Trustee may determine,  to the Holders
  of such Securities, of  all sums due and  to become due thereon  in respect
  of principal and  any premium and  interest, but money so  held in trust
  need not be  segregated upon other  funds except to the extent required  by
  law.  The  Company shall pay and  indemnity the Trustee against any tax,  fee
  or other  charge imposed  on or  assessed  against the  U.S. Government
  Obligations  deposited pursuant to Section 9.04 hereof or the principal and
  interest received in





                                       67
<PAGE>   75
  respect thereof other  than any such  tax, fee  or other  charge which by
  law is for the account of  the Holders  of outstanding Securities.

                   Anything in this  Article 9 to the contrary notwithstanding,
  the Trustee shall  deliver or pay to  the Company from time  to time upon
  Company  Order any money  or U.S. Government Obligations  held by it as
  provided in Section  9.04 hereof which, in  the opinion of a nationally
  recognized firm of independent  public accountants expressed  in a  written
  certification  thereof delivered  to the  Trustee, are in  excess of  the
  amount thereof that  would then be required  to be deposited to effect  the
  Defeasance or Covenant  Defeasance, as the case may be, with respect to the
  outstanding Securities.

                   SECTION  9.06   Repayment to  Company.   Any money deposited
  with the  Trustee or  any Paying Agent,  or then  held  by the  Company, in
  trust for  the payment  of the  principal of,  premium, if  any, or interest,
  if any,  on any Security  and remaining  unclaimed for  two years after  such
  principal, premium,  if any, or interest, if any, have become due and payable
  shall be paid to the Company on  its request or (if then held by the Company)
  shall  be discharged from such trust;  and the Holder of such Security shall
  thereafter, as an unsecured  general creditor,  look only to  the Company
  for payment  thereof, and  all liability of  the Company as trustee  thereof,
  shall thereupon  cease; provided  that the Trustee  or such Paying  Agent,
  before being  required to make any such repayment, may at  the expense of the
  Company cause  to be published once, in the New York Times  and The Wall
  Street  Journal (national edition),  notice that such money  remains
  unclaimed and that,  after a  date specified  therein, which  shall not  be
  less  than 30  days from  the  date of  such notification or  publication,
  any unclaimed  balance of  such money  then  remaining will  be repaid  to
  the Company.

                   SECTION  9.07  Reinstatement.  If the Trustee or Paying
  Agent is  unable to apply any money in accordance with this Article 9  with
  respect to any Notes by  reason of any order or judgment of any  court or
  governmental authority enjoining, restraining  or otherwise prohibiting such
  application, then the obligations under this Indenture, the  Guarantees and
  such Securities  from which the  Company or the Guarantors  have been
  discharged or released pursuant  to Section 9.02 or 9.03  hereof shall be
  revived and reinstated as  though no deposit had occurred  pursuant to  this
  Article  9 with respect to  such Securities,  until such  time as  the
  Trustee  or Paying Agent is  permitted to apply all  money held in trust
  pursuant to  Section 9.05 hereof with respect to such Securities  in
  accordance with this Article  9; provided that if the  Company or any
  Guarantor makes  any payment  of  principal  of, premium,  if  any, or
  interest  on  any such  Security  following  such reinstatement  of its
  obligations, the Company  or such Guarantor, as the case may  be, shall be
  subrogated to the Holders of such Securities to receive such payment from the
  money so held in trust.





                                       68
<PAGE>   76
                                   ARTICLE 10

                                   Amendments

                   SECTION 10.01.  Without Consent of Holders.

                   (a)      The Company, the Guarantors  and the Trustee may at
  any time and from time  to time, without notice  to or consent of  any
  Holder, enter into  one or more indentures  supplemental hereto, in  form
  satisfactory to the Trustee, for any of the following purposes:

                        (i)         to  evidence  the  succession  of  another
                   Person to  the  Company  and  the Guarantors  and the
                   assumption by such  successor of the covenants  and
                   Obligations   of the Company under this Indenture and
                   contained in the Securities and  the Guarantors contained in
                   this Indenture and the Guarantees;

                        (ii)        to add to the covenants  of the Company,
                   for the  benefit of the  Holders, or to  surrender any
                   right  or power  conferred  upon the  Company  or the
                   Guarantors  by  this Indenture;

                       (iii)       to add any additional Events of Default;

                       (iv)        to provide  for  uncertificated  Securities
                   in  addition to  or  in place  of certificated Securities;

                       (v)         to  evidence  and  provide  for  the
                   acceptance  of  appointment  under this Indenture by the
                   successor Trustee;

                       (vi)         to secure the Securities and/or the 
                   Guarantees;

                       (vii)        to  cure any  ambiguity,  to correct  or
                   supplement  any  provision in  this Indenture which  may be
                   inconsistent with any  other provision  therein or to  add
                   any other provisions with respect  to matters or questions
                   arising  under this Indenture, provided  that such actions
                   will not adversely affect the interests  of the Holders in
                   any  material respect; or

                       (viii)       to add or release any Guarantor pursuant 
                   to the terms of this Indenture.





                                       69
<PAGE>   77
                   SECTION 10.02.   With Consent  of Holders.   With the
  consent of  the Holders  of at least  a majority  of the  principal amount
  at  Stated  Maturity of  the  outstanding  Securities (including  consents
  obtained  in connection with a tender offer or an exchange offer for  the
  Securities), by Act delivered to the Company, the Guarantors and  the
  Trustee, the Company,  the Guarantors and the  Trustee may enter  into one
  or more indentures supplemental  hereto for the purpose of  adding any
  provisions to  or changing or  eliminating any of the provisions  of this
  Indenture  or modifying  the rights of the  Holders of the Securities,
  provided that no such supplemental indenture,  without the consent of the
  Holder  of each outstanding Security affected thereby, will:

                   (a)      change  the Stated Maturity of the  principal of,
  or any  installment of interest on, any Security, or reduce the principal
  amount thereof  (or any premium, if any), or the  interest thereon, that
  would be  due and  payable upon  Maturity thereof, or  change the  place of
  payment  where, or  in the coin  or currency  in which,  any Security  or
  any premium  or interest  thereon is  payable,  or  impair the  right to
  institute suit for the enforcement of any such payment on or after the Stated
  Maturity thereof; or

                   (b)      reduce the percentage in principal amount at Stated
  Maturity of the outstanding Securities, the consent of whose Holders is
  required for any such supplemental indenture or required for any waiver of
  compliance with the provisions of this Indenture; or

                   (c)      modify any of the provisions of Section 6.04
  hereof, except to increase the percentage set forth therein or to provide
  that certain other provisions of this Indenture cannot be amended or waived
  without the consent of the Holder of each outstanding Security affected
  thereby; or

                   (d)      subordinate in right of payment, or otherwise
  subordinate, the Securities or the Guarantees to any other Indebtedness; or

                   (e)      modify any provision of  this Indenture relating to
  the obligations of the Company to make offers to purchase Securities upon a
  Change of Control or from the proceeds of an Asset Sale; or

                   (f)      modify any of the provisions of this  Section 10.02
  except to increase any percentage set forth herein or to  provide that
  certain other provisions of this  Indenture cannot be modified or  waived
  without the consent of the Holders of each outstanding Security affected
  thereby; or

                   (g)      amend, supplement or otherwise  modify the
  provisions  of this Indenture relating  to the Guarantees.

                   It shall not  be necessary for  any Act  of Holders  under
  this Section  10.02 to approve  the particular form of any  proposed
  supplemental indenture, but it shall  be sufficient if such Act shall
  approve the substance thereof.





                                       70
<PAGE>   78
                   SECTION 10.03   Effect of  Supplemental Indentures.   Upon
  the execution of  any supplemental indenture  under  this  Article  10, this
  Indenture  shall  be  modified  in  accordance  therewith, and  such
  supplemental indenture shall form  a part of this  Indenture for all
  purposes; and every Holder  of Securities theretofore or thereafter
  authenticated  and delivered hereunder shall be  bound thereby.  After a
  supplemental indenture becomes  effective, the Company  shall mail to
  Holders a  notice briefly describing  such amendment.  The  failure to  give
  such  notice to  all Holders,  or any  defect therein,  shall not  impair or
  affect the validity of an amendment under this Section.

                   SECTION 10.04.   Compliance with Trust  Indenture Act.
  Every  amendment to  this Indenture or the Securities shall comply with the
  Trust Indenture Act as then in effect.

         SECTION 10.05.  Revocation and Effect of Consents and Waivers.

                   (a)      A consent  to an  amendment or  a waiver  by a
  Holder  of a  Security shall  bind the Holder  and every subsequent Holder of
  that Security  or portion of the Security  that evidences the same debt as
  the consenting Holder's Security, even  if notation of the consent  or waiver
  is not made on the Security.  However, any such Holder or  subsequent Holder
  may revoke the  consent or waiver as to such Holder's  Security or portion of
  the Security if  the Trustee receives the notice of revocation  before the
  date the amendment or waiver becomes effective.   After an  amendment or
  waiver becomes effective, it  shall bind every Holder.   An amendment or
  waiver  becomes effective  upon  the  execution  of a  supplemental
  indenture  containing  such amendment or waiver by the Trustee.

                   (b)      The Company may, but shall not be obligated to, fix
  a record date for the purpose  of determining the Holders  entitled to give
  their  consent or take any other  action described above or  required or
  permitted to  be taken pursuant to  this Indenture.   If a record  date is
  fixed, then notwithstanding  the immediately  preceding  subsection, those
  Persons  who  were  Holders  at  such  record date  (or  their  duly
  designated proxies),  and only those Persons, shall be entitled to give such
  consent or to revoke any consent previously  given or to take any such
  action, whether or not  such Persons continue to  be Holders after such
  record date.  No such consent shall be valid or effective for more than 120
  days after such record date.

                   SECTION 10.06.  Notation on or Exchange of  Securities.  If
  an amendment changes  the terms of a Security, the  Trustee may require the
  Holder of the Security to deliver it to the  Trustee.  The Trustee may place
  an appropriate  notation on  the Security  regarding  the  changed terms  and
  return  it to  the Holder.  Alternatively, if  the Company or the  Trustee so
  determines,  the Company in exchange  for the Security  shall issue and the
  Trustee shall authenticate a  new Security that reflects the changed terms.
  Failure to make the appropriate notation or to issue a new Security shall not
  affect the validity of such amendment.

                   SECTION 10.07.   Trustee To Execute  Supplemental
  Indentures.  The  Trustee shall execute any supplemental  indenture
  authorized  pursuant  to this  Article 10  if  such  supplemental indenture
  does  not adversely  affect the rights, duties, liabilities or immunities of
  the Trustee.   If it does, the Trustee may, but shall not be required to,
  execute such supplemental





                                       71
<PAGE>   79
  indenture.   In  executing any  supplemental  indenture,  the Trustee  shall
  be  entitled to  receive indemnity reasonably satisfactory to  it and to
  receive,  and (subject to Section 7.01  hereof) shall be fully  protected in
  relying upon, an Officers'  Certificate (which need only cover  the matters
  set forth in  clause (a) below) and an Opinion of Counsel provided by the
  Company stating that:

                   (a)      such supplemental indenture  is authorized or
  permitted by this  Indenture and  that all conditions  precedent to the
  execution, delivery and performance of such  supplemental indenture have been
  satisfied:

                   (b)      the Company  and the Guarantors have  all necessary
  corporate power  and authority to execute  and deliver  the  supplemental
  indenture and  that the  execution, delivery  and performance  of such
  supplemental indenture  has been duly  authorized by  all necessary
  corporate action  of the  Company and  the Guarantors;

                   (c)      the execution,  delivery  and  performance  of  the
  supplemental  indenture  do  not conflict with,  or result in  the breach  of
  or  constitute a default  under any  of the terms, conditions  or provisions
  of (i) this Indenture, (ii) the charter  documents and by-laws of the Company
  or any Guarantor, or (iii) any material agreement or instrument to which the
  Company or any Guarantor is subject and of which such counsel is aware;

                   (d)      to  the knowledge of  legal counsel writing  such
  Opinion of  Counsel, the execution, delivery and  performance of the
  supplemental indenture  do not conflict with, or result in  the breach of any
  of  the terms,  conditions  or provisions  of (i)  any law  or regulation
  applicable  to the  company  or any Guarantor,  or  (ii)   any  material
  order,  writ,  injunction  or   decree  of  any  court  or   governmental
  instrumentality applicable to the Company or any Guarantor;

                   (e)      such supplemental indenture has been duly  and
  validly executed and delivered by  the Company and  the Guarantors, and  the
  Indenture together with such supplemental  indenture constitutes a legal,
  valid  and binding  obligations of  the Company and  the Guarantors
  enforceable against  the Company  and the Guarantors, as  applicable, in
  accordance  with its  terms, except  as such  enforceability may  be limited
  by applicable  bankruptcy, insolvency, or similar laws  affecting the
  enforcement of  creditors  rights generally and general equitable principles;
  and

                   (f)      the Indenture  together with  such amendment or
  supplement complies  with the  Trust Indenture Act.

                   SECTION 10.08.  Payment  for Consent.  Neither  the Company
  nor any  Affiliate of the Company shall, directly or indirectly, pay or cause
  to be paid  any consideration, whether by way of interest,  fee or otherwise,
  to any Holder for  or as an inducement to any  consent, waiver or amendment
  of any of the  terms or provisions of this Indenture or the Securities
  unless such consideration is offered to  be paid to all Holders that  so
  consent, waive or  agree to amend in  the time frame set forth in
  solicitation documents relating to such consent, waiver or agreement.





                                       72
<PAGE>   80
                                   ARTICLE 11

                                   Guarantees

                   SECTION 11.01.  Guarantees.

                   (a)      For good and valuable consideration, the receipt
  and sufficiency of  which are hereby acknowledged, each  of the Guarantors,
  together with each Subsidiary  of the Company which  in accordance with
  Section 11.08 is required in the  future to guarantee the Obligations of the
  Company and the  Guarantors under the Securities, the  Guarantees and this
  Indenture upon execution  of a supplemental indenture, hereby  jointly and
  severally  and irrevocably and unconditionally guarantees to  the Trustee and
  to  each Holder of a Security authenticated and delivered by  the Trustee
  irrespective of  the validity  or enforceability of this  Indenture or the
  Securities or the Obligations  of the Company and  the Guarantors under  this
  Indenture,  that: (i) the principal  of,  premium,  if any,  and any
  interest,  on the  Securities (including,  without  limitation, any interest
  that accrues  after the filing of a proceeding of the type described in
  Sections 6.01(g) and (h)) and any fees, expenses and other  amounts owing
  under this Indenture will be duly and punctually paid in full when due,
  whether  at Stated Maturity, by acceleration, call  for redemption, upon a
  Change of Control Offer, Asset Sale Offer, purchase or otherwise, and
  interest on the overdue  principal and (to the extent permitted  by law)
  interest,  if any, on the Securities  and any other  amounts due in respect
  of the Securities,  and all other Obligations of the Company and  the
  Guarantors to the Holders  of the Securities under this  Indenture and the
  Securities,  whether now or hereafter  existing, will be  promptly paid  in
  full or performed,  all strictly in accordance with the terms hereof and of
  the Securities; and (ii)  in case of any extension of time of  payment or
  renewal of any Securities  or any of such  other Obligations, the same  will
  be promptly paid  in full when due or performed in accordance  with the terms
  of the extension  or renewal, whether  at Stated Maturity,  by acceleration,
  call for redemption, upon Change of Control  Offer, Asset Sale Offer,
  purchase or  otherwise.  If payment is not made when due of  any amount so
  guaranteed for whatever reason, each Guarantor shall be jointly and severally
  obligated to pay  the same individually whether or  not such failure to pay
  has become an Event of  Default which could cause acceleration  pursuant to
  Section  6.02.  Each  Guarantor agrees that  this is a guarantee  of payment
  and  not a guarantee of  collection.  An  Event of  Default under this
  Indenture or the Securities  shall constitute  an  Event of  Default under
  this Guarantee,  and shall  entitle the  Holders to accelerate the
  Obligations  of each  Guarantor hereunder  in the same manner  and to  the
  same  extent as  the Obligations of  the Company.  This Guarantee  is
  intended to be superior to or pari  passu in right of payment with all
  Indebtedness of the Guarantors and each Guarantor s Obligations are
  independent of any Obligation of the Company or any other Guarantor.

                   (b)      Each  Guarantor waives presentation  to, demand of,
  payment from and  protest to the Company of  any of  the Obligations under
  this  Indenture or the Securities  and also waives notice  of protest for
  nonpayment.  Each  Guarantor waives notice of  any default under the
  Securities or the  Obligations.   The Obligations of each Guarantor hereunder
  shall not be affected by (a) the failure of any  Holder or the Trustee to
  assert any  claim or demand or to enforce any right or remedy against the
  Company  or any other Person under this Indenture, the Securities or





                                       73
<PAGE>   81





  any  other agreement or otherwise;  (b) any extension  or renewal  of any
  thereof; (c)  any rescission, waiver, amendment or modification  of any of
  the terms  or provisions of this  Indenture, the Securities or  any other
  agreement; (d) the  release of any security  held by any  Holder or the
  Trustee  for the Obligations or  any of them; (e)  the failure  of  any
  Holder  or the  Trustee to  exercise any  right or  remedy against  any
  other guarantor of the Obligations; or (f) any change in the ownership of
  such Guarantor.

                   (c)      The Obligations  of each Guarantor hereunder  shall
  not be subject  to any reduction, limitation,  impairment or  termination for
  any reason, including  any claim  of waiver,  release, surrender, alteration
  or  compromise, and shall  not be  subject to  any defense  of setoff,
  counterclaim, recoupment  or termination whatsoever  or by reason of  the
  invalidity, illegality or  unenforceability of the Obligations  of the
  Company  or otherwise.    Without limiting  the generality  of  the
  foregoing,  the  Obligations  of each Guarantor herein  shall not be
  discharged  or impaired or otherwise  affected by the failure  of any Holder
  or the Trustee to  assert any claim or  demand or to enforce any remedy
  under this Indenture, the  Securities or any other agreement,  by any waiver
  or modification of any thereof, by any  default, failure or delay, willful or
  otherwise, in the performance of  the Obligations of the Company, or by  any
  other act or  thing or omission or delay to do any other act or thing which
  may or might in any manner  or to any extent vary the risk of  such Guarantor
  or would otherwise operate as a discharge of such Guarantor as a matter of
  law or equity.

                   (d)      Each  Guarantor  further  agrees  that  its
  Guarantee  herein  shall  continue  to be effective or be  reinstated, as the
  case may be, if at any time payment, or any  part thereof, of principal of,
  premium, if any,  on or interest on any Obligation of the  Company is
  rescinded or must  otherwise be restored by any Holder or the Trustee upon
  the bankruptcy or reorganization of the Company or otherwise.

                   (e)      In furtherance of  the foregoing and not  in
  limitation of any other  right which any Holder or the  Trustee has at law or
  in equity against any Guarantor by virtue hereof,  upon the failure of the
  Company to pay  the principal of, premium, if any, on or interest on any
  Obligation when  and as the same shall become  due, whether at maturity,  by
  acceleration, by  redemption or  otherwise, or to perform  or comply with any
  other  Obligation, each  Guarantor hereby  promises to  and will,  upon
  receipt  of written  demand by  the Trustee, forthwith pay,  or cause to be
  paid,  in cash, to the  Holders or the Trustee an amount equal  to the sum of
  (i) the  unpaid amount of such Obligations,  (ii) accrued and unpaid interest
  on such  Obligations (but only to  the extent not  prohibited by law)  and
  (iii) all other  monetary Obligations of  the Company  to the Holders and the
  Trustee.

                   (f)      Until  such  time  as  the  Securities  and  the
  other  Obligations  of the  Company guaranteed hereby have  been satisfied in
  full, each  Guarantor hereby irrevocably waives  any claim or  other rights
  that it may now  or hereafter acquire against  the Company or any  other
  Guarantor that arise  from the existence,  payment,  performance  or
  enforcement  of  such  Guarantor's  Obligations  under  this  Guarantee,
  including,  without  limitation,  any  right  of  subrogation,
  reimbursement,  exoneration,  contribution  or indemnification and any right
  to participate in any claim or remedy of the Holders or  the Trustee against
  the Company or any





                                       74
<PAGE>   82
  other Guarantor  or  any security,  whether or  not such  claim,  remedy  or
  right  arises in  equity or  under contract, statute or common law,
  including,  without limitation, the right to take or receive from the
  Company or  any other Guarantor,  directly or  indirectly, in cash or  other
  property  or by set-off  or in  any other manner, payment or security on
  account of such claim, remedy or  right.  If any amount shall be paid  to
  such Guarantor in violation of  the preceding sentence at  any time prior  to
  the later of  the payments in full  of the Securities and all  other amounts
  payable under this Indenture,  this Guarantee and the Stated Maturity  of the
  Notes, such  amount shall  be held  in trust  for the  benefit of  the
  Holders  and the  Trustee and shall forthwith be paid to  the Trustee to be
  credited and applied to  the Notes and all other amounts payable  under this
  Guarantee, whether  matured or unmatured, in accordance  with the terms of
  this Indenture, or  to be held as security for any Obligations or other
  amounts payable under this Guarantee thereafter arising.

                   (g)      Each Guarantor acknowledges that  it will receive
  direct and indirect benefits  from the financing arrangements contemplated by
  this Indenture and  that the waiver set forth in  this Section 11.01 is
  knowingly made in contemplation  of such benefits.  Each Guarantor further
  agrees that, as between it,  on the  one hand,  and the  Holders and  the
  Trustee,  on the  other hand,  (x)  subject to  this Article  11, the
  maturity  of the Obligations guaranteed hereby may  be accelerated as
  provided in Article 6 for the purposes of this Guarantee,  notwithstanding
  any  stay, injunction  or other  prohibition preventing  such acceleration in
  respect of  the Obligations guaranteed hereby,  and (y) in  the event of any
  acceleration of such  Obligations guaranteed hereby as provided  in Article
  6, such  Obligations (whether or  not due and payable)  shall further then
  become due and payable by the Guarantors for the purposes of this Guarantee.

                   (h)      A Guarantor that makes a  distribution or payment
  under a Guarantee shall be entitled to contribution  from each other
  Guarantor in a pro rata  amount based on the Adjusted Net Assets  of each
  such other  Guarantor  for all  payments,  damages  and expenses  incurred
  by  that Guarantor  in  discharging  the Company s obligations with respect
  to the Securities and  this Indenture or any  other Guarantor with respect to
  its Guarantee, so  long as the  exercise of such  right does not  impair the
  rights  of the  Holders of the Securities under the Guarantees.

                   (i)      Each  Guarantor  also  agrees to  pay  any  and
  all  costs and  expenses  (including reasonable attorneys' fees) incurred by
  the Trustee or any Holder in enforcing any rights under this Section.

                   SECTION 11.02.   Limitation on  Liability.   Any term or
  provision of this  Indenture to  the contrary  notwithstanding,  the  maximum
  aggregate  amount  of  the  Obligations  guaranteed  hereunder by  any
  Guarantor  shall not exceed the maximum  amount that can be hereby guaranteed
  without rendering this Indenture, as  it relates to such Guarantor, void,
  voidable or unenforceable  under applicable law relating to fraudulent
  conveyance  or fraudulent transfer or similar laws affecting the rights of
  creditors generally.  To effectuate the  foregoing intention, the Obligations
  of each Guarantor  shall be  limited to the maximum  amount as will, after
  giving effect  to all other contingent  and fixed liabilities of such
  Guarantor and after giving  effect to any collections from or payments  made
  by or on behalf of any  other Guarantor in respect of the Obligations of such
  other Guarantor under  its Guarantee or pursuant to its  contribution
  Obligations hereunder, result in the Obligations of such Guarantor under its





                                       75
<PAGE>   83
  Guarantee  not constituting  a fraudulent conveyance  or fraudulent  transfer
  under federal, state  or foreign law.    Each Guarantor  that  makes a
  payment or  distribution  under  a Guarantee  shall  be  entitled to  a
  contribution  from each  other Guarantor  in a  pro  rata amount  based  on
  the  Adjusted Net  Assets  of each Guarantor.

                   SECTION  11.03  Execution and Delivery of  Guarantees.  To
  further evidence  its Guarantee set forth in Section 11.01 hereof, each
  Guarantor hereby  agrees that notation of such Guarantee  shall be endorsed
  on  each Security  authenticated and  delivered by  the Trustee  and executed
  by either  manual  or facsimile signature  of an authorized officer  of such
  Guarantor.   Each  Guarantor hereby agrees that  its Guarantee set forth in
  Section 11.01 hereof shall remain in  full force and effect notwithstanding
  any  failure to endorse on each Note a  notation of such Guarantee.  If an
  officer of a Guarantor whose signature  is on this Indenture or a Security
  no longer holds  that office at the time  the Trustee authenticates  such
  Security or at  any time thereafter, such Guarantor's  Guarantee of such
  Security shall  be valid nevertheless.   The delivery  of any Security by the
  Trustee,  after the  authentication thereof hereunder,  shall constitute  due
  delivery of  any Guarantee set forth in this Indenture on behalf of the
  Guarantor.

                   SECTION 11.04   When  a Guarantor  May Merge,  etc.   No
  Guarantor  shall consolidate with  or merge with  or into (whether  or not
  such  Guarantor is the  surviving person) another  corporation, Person  or
  entity whether or not affiliated with such Guarantor  (but excluding any
  consolidation, amalgamation  or merger if the  surviving corporation is no
  longer a  Subsidiary) unless (i) subject to the provisions of Section 11.07
  hereof, the Person  formed by or  surviving any  such consolidation  or
  merger (if  other than such  Guarantor) assumes  all  the Obligations  of
  such  Guarantor  pursuant to  a  supplemental indenture  in  form reasonably
  satisfactory  to the Trustee under the Securities and this Indenture  and
  (ii) immediately after giving effect to such transaction, no Default  or
  Event of  Default exists.   In connection with  any such consolidation  or
  merger, the Trustee shall  be entitled to receive  an Officers' Certificate
  and an Opinion of  Counsel stating that such consolidation or merger is
  permitted by this Section 11.04.

                   SECTION 11.05.   No  Waiver.  Neither a failure  nor a delay
  on the part of either the Trustee or the Holders  in exercising any right,
  power or  privilege under this Article  11 shall operate as  a waiver
  thereof, nor shall a single or partial  exercise thereof preclude any other
  or further exercise of any  right, power  or privilege.   The  rights,
  remedies  and  benefits  of the  Trustee and  the Holders  herein expressly
  specified are  cumulative and not exclusive  of any other  rights, remedies
  or benefits  which either may  have under this Article 11 at law, in equity,
  by statute or otherwise.

                   SECTION 11.06.   Modification.  No modification,  amendment
  or waiver of any provision of this Article  11, nor the  consent to  any
  departure  by any  Guarantor therefrom, shall  in any event  be effective
  unless the same  shall be  in writing  and signed  by the Trustee,  and then
  such waiver or  consent shall  be effective only in the specific  instance
  and for the purpose for  which given.  No notice to or demand  on any
  Guarantor in any  case shall entitle  such Guarantor to any  other or further
  notice or  demand in the  same, similar or other circumstances.





                                       76
<PAGE>   84
                   SECTION 11.07.   Release of Guarantor.  Upon the  sale or
  other transfer of all of the Capital Stock of a  Guarantor to any Person that
  is not an Affiliate  of the Company in compliance with the  terms of this
  Indenture (including, without limitation, Section 4.07 hereof) and in a
  transaction that does not result in a Default  or an Event of  Default being
  in existence or  continuing immediately thereafter, such  Guarantor shall be
  deemed automatically and unconditionally  released and  discharged from  all
  obligations under  this Indenture without any  further action required on the
  part of the Trustee or any Holder; provided that the Net Available  Proceeds
  of such  sale or  other disposition  are applied  in accordance  with Section
  4.07  of this Indenture as if such  sale or disposition were an Asset Sale
  and in accordance with the applicable provisions of this  Indenture.  The
  Trustee shall  deliver at the  expense of  the Company  an appropriate
  instrument or instruments evidencing such  release upon  receipt of  a
  request of  the Company  accompanied by  an Officers' Certificate  and Opinion
  of  Counsel certifying  as to  the compliance  with this  Section 11.07 and
  the other applicable provisions of this Indenture.

                   SECTION 11.08.   Execution of  Supplemental  Indentures  for
  Future  Guarantors.   Any  Wholly Owned Subsidiary that is a domestic
  Subsidiary or  any other Subsidiary that guarantees any  Indebtedness of an
  Obligor  is required  to become  a Guarantor  and the  Company shall  cause
  each  such Subsidiary  to  promptly execute and deliver  to the Trustee a
  supplemental indenture in the form of Exhibit C hereto pursuant to which such
  Subsidiary  shall become a  Guarantor under this  Article 11 and  shall
  guarantee the  Obligations of  the Company under  the Securities  and this
  Indenture.   Concurrently  with the  execution and  delivery of  such
  supplemental indenture,  the Company shall  deliver to the  Trustee an
  Opinion  of Counsel to  the effect  that such supplemental indenture has
  been duly  authorized, executed and  delivered by  such Subsidiary and  that,
  subject to the  application of bankruptcy, insolvency, moratorium, fraudulent
  conveyance or  transfer and other similar laws relating to creditors' rights
  generally and  to the principles of equity, whether  considered in a
  proceeding at law or  in equity, the Guarantee of  such Guarantor is a legal,
  valid and binding  obligation of such Guarantor, enforceable  against such
  Guarantor  in accordance  with its  terms, and as  to any such  other matters
  as the Trustee may reasonably request.





                                       77
<PAGE>   85





                                   ARTICLE 12

                                 Miscellaneous

                   SECTION 12.01.   Compliance Certificates and  Opinions.
  Upon  any application or  request by the Company or  the Guarantors to the
  Trustee to take any  action under any provision of this  Indenture, the
  Company and the Guarantors, as  applicable, shall furnish to the Trustee, to
  the extent required by the TIA or this Indenture,  (i) an Officers'
  Certificate stating that all  conditions precedent, if any,  provided for in
  this  Indenture (including any covenant, compliance  with which constitutes a
  condition precedent) relating to the  proposed action have been complied
  with and (ii)  an Opinion of Counsel  stating that in  the opinion of such
  counsel all such conditions precedent, if any, have  been complied with,
  except that  in the case of any such application  or request  as to which
  the furnishing  of such documents  is specifically  required by  any
  provision  of this Indenture relating to such  particular application or
  request, no  additional certificate or opinion need be furnished.

                   Every  certificate  or  opinion  with  respect  to
  compliance  with  a  condition  or covenant provided for in this Indenture
  shall include:

           (1)     a statement that each  individual signing such certificate
  or opinion has read  such covenant or condition and the definitions herein
  relating thereto;

           (2)     a brief statement as to  the nature and scope of the
  examination or investigation upon which the statements or opinions contained
  in such certificate or opinion are based;

           (3)     a statement that,  in the opinion of  each such individual,
  he has made  such examination or investigation as is necessary to enable him
  to express an informed opinion as to whether or not such covenant or
  condition has been complied with; and

           (4)     a statement  as to whether or not, in  the opinion of each
  such individual, such condition or covenant has been complied with.

                   SECTION 12.02.   Form of Documents Delivered to Trustee.
  In any case  where several matters are required to  be certified by, or
  covered by an opinion of, any specified Person,  it is not necessary that all
  such matters be  certified by, or  covered by the  opinion of, only  one such
  Person,  or that  they be so certified or covered by  only one document, but
  one such Person  may certify or give an opinion with respect to some  matters
  and one or more other such Persons  as to other matters, and any such Person
  may certify or give an opinion as to such matters in one or several
  documents.

           Any certificate or opinion  of an officer of the Company or any
  Guarantor  may be based, insofar as it relates to legal  matters, upon  a
  certificate  or opinion  of, or  representations by,  counsel, unless  such
  officer  knows,  or in  the  exercise of  reasonable  care  should know,
  that  the certificate  or  opinion or representations with respect to the
  matters upon which his certificate or





                                       78
<PAGE>   86
  opinion is based are erroneous.   Any such certificate or  opinion of counsel
  may be based, and may  state that it  is  so  based,  insofar  as  it
  relates  to  factual  matters,  upon  a  certificate  or  opinion  of,  or
  representations by, an officer or officers of the  Company or such Guarantor
  stating that  the information with respect to such factual  matters is in the
  possession of the Company  or such Guarantor,  unless such  counsel knows, or
  in the exercise of reasonable care  should know, that the  certificate of
  opinion or representations with respect to such matters are erroneous.

           Where any Person is  required to make, give or  execute two or more
  applications,  requests, consents, certificates, statements,  opinions or
  other instruments  under this  Indenture, they  may, but  need not,  be
  consolidated and form one instrument.

                   SECTION 12.03.  Acts of Holders.

           (a)     Any  request, demand,  authorization,  direction,  notice,
  consent,  waiver or  other  action provided by this  Indenture to be given or
  taken by a specified percentage of Holders may  be embodied in and evidenced
  by one  or more instruments of  substantially similar tenor  signed by such
  specified percentage of Holders in person or by agents duly appointed  in
  writing; and, except as herein  otherwise expressly provided, such action
  shall become effective when  such instrument or instruments are received by
  the Trustee and,  where it is hereby expressly required, to the Company and
  the  Guarantors.  Such instrument or instruments (and  the action embodied
  therein  and evidenced thereby) are  herein sometimes referred to as  the
  "Act" of the  Holders signing such instrument or  instruments.  Proof of
  execution of any such instrument or of  a writing appointing any such agent
  shall be sufficient for any purpose of this Indenture and (subject  to
  Sections 7.01 and 7.02) conclusive  in favor of the  Trustee, the Company and
  the Guarantors, if made in the  manner provided in this Section.

           (b)     The  fact and date of  the execution by any  Person of any
  such instrument  or writing may be proved by  the affidavit  of a  witness of
  such execution or  by a  certificate of  a notary  public or  other officer
  authorized  by  law to  take acknowledgments  of deeds,  certifying that  the
  individual  signing such instrument or writing acknowledged  to him the
  execution thereof.  Where  such execution is by a signer acting in a
  capacity  other than  his  individual capacity,  such  certificate  or
  affidavit shall  also  constitute sufficient proof  of authority.  The  fact
  and date of the execution of any  such instrument or writing, or the
  authority  of the Person executing  the same, may also  be proved in any
  other manner  which the Trustee deems sufficient, including the execution of
  such instrument or writing without more.

           (c)     The ownership,  principal amount and serial numbers  of
  Securities held by any Person, and the date of holding the same, shall be
  proved by the Security Register.

           (d)     If  the  Company  shall   solicit  from  the  Holders  of
  Securities  any  request,   demand, authorization, direction,  notice,
  consent,  waiver  or other  Act,  the Company  may, at  its option,  by  or
  pursuant  to Board Resolution, fix in advance a record date for  the
  determination of Holders entitled to give such request, demand,
  authorization,  direction, notice, consent, waiver  or other Act, but  the
  Company  shall have  no obligation to  do so.   Such record date  shall be
  the  record date specified  in or  pursuant to such Board Resolution, which
  shall be a date not earlier than the





                                       79
<PAGE>   87
  date 30 days  prior to the first solicitation  is completed.  If  such a
  record  date is fixed, such  request, demand, authorization,  direction,
  notice,  consent, waiver  or other  Act may  be given  before or after  such
  record date, but only the  Holders of record at the close  of business on
  such record date shall be  deemed to be Holders  for  the  purposes  of
  determining  whether  Holders of  the  requisite proportion  of  outstanding
  Securities have authorized or agreed or consented  to such request, demand,
  authorization,  direction, notice, consent, waiver or other  Act, and for
  that purpose  the outstanding Securities shall  be computed as of  such
  record date; provided  that no such  authorization, agreement  or consent  by
  the Holders  on such record  date shall be deemed  effective unless it shall
  become effective pursuant to the  provisions of this Indenture  not later
  than eleven months after the record date.

           (e)     Except to  the extent  otherwise expressly provided  in this
  Indenture,  any request,  demand, authorization, direction, notice, consent,
  waiver or  other Act of the Holder of any Security shall bind  every future
  Holder of the same Security and  the Holder of every Security issued upon the
  registration of  transfer thereof or in  exchange therefor or  in lieu
  thereof  in respect of anything done,  omitted or suffered  to be done by the
  Trustee or the Company in  reliance thereon, whether or not notation of such
  action is made upon such Security.

           (f)     Without limiting the foregoing,  a Holder entitled
  hereunder to give or take any  action with regard to any  particular Security
  may do so  with regard to all  or any part of the principal amount  of such
  Security or  by one or more  duly appointed agents  each of which may  do so
  pursuant to  such appointment with regard to all or any different part of
  such principal amount.

                   SECTION  12.04.  Trust  Indenture Act Controls.   If any
  provision of  this Indenture limits, qualifies  or  conflicts with  another
  provision  which is  required  to  be  included  in  this Indenture  by
  Sections 310 to 318,  inclusive, of the  Trust Indenture Act, the  required
  provision shall  control.  If  any provision  of this  Indenture  modifies or
  excludes any  provision  of the  TIA that  may be  so modified  or excluded,
  the latter provision shall be  deemed to apply to this Indenture as  so
  modified or excluded, as the case may be.

                   SECTION 12.05.   Notices.  Any notice  or communication
  shall be in writing and  delivered in person, or sent  by registered or
  certified mail,  by air  courier guaranteeing overnight  delivery or by  fax
  (promptly confirmed by telephone) and addressed as follows:

           if to the Company or any Guarantor:

                   DI Industries, Inc.
                   10370 Richmond Avenue
                   Suite 600
                   Houston, Texas  77042
                   Attn:  Chief Financial Officer
                   Phone: (281) 435-6100
                   Fax:   (281) 435-6171





                                       80
<PAGE>   88
           if to the Trustee:

                   Texas Commerce Bank National Association
                   600 Travis Street, Suite 1150
                   Houston, Texas  77002
                   Attention:  Corporate Trust Division
                   Phone: (713) 216-5811
                   Fax:   (713) 216-5476

           with a copy to the Trustees Dallas Payment Office:

                   Texas Commerce Bank National Association
                   1201 Main Street
                   Dallas, Texas  75202
                   Attn:  Corporate Trust Services

                   The Company, the  Guarantors or the Trustee by notice  to
  the others may designate  additional or different addresses for subsequent
  notices or communications.

                   Any notice  or communication mailed to  a Holder shall  be
  sent to the  Holder by first  class mail, postage prepaid,  at the Holder's
  address as it appears in  the Security Register and shall  be given if so
  sent within  the time prescribed.  Failure to mail a notice or communications
  to a  Holder or any default in it shall not affect its  sufficiency with
  respect to other Holders.  If a notice or communication  is mailed or faxed
  to the Company, the Guarantors, the Trustee  or a Holder in the manner
  provided  above, it is duly given, whether or not  the addressee receives it
  but shall not be  effective unless in the  case of the Company,  the
  Guarantors or the Trustee  actually received.  In case by reason  of the
  suspension of regular mail service or by  reason or  any other  cause  it
  shall  be impracticable  to  give notice  by  mail to  Holders,  then such
  notification as shall be made with  the approval of the Trustee shall
  constitute a sufficient notification  for every purpose hereunder.

                   SECTION 12.06.    Communication  by  Holders with  Other
  Holders.   Holders  may  communicate pursuant to  TIA Section 312(b)  with
  other  Holders with respect to  their rights under this  Indenture or the
  Securities.    The Company,  the  Guarantors,  the Trustee,  the  Registrar
  and  anyone  else  shall have  the protection of TIA Section 312(c).

                   SECTION  12.07.   Rules  by  Trustee,  Paying  Agent  and
  Registrar.    The  Trustee may  make reasonable  rules for  action by  or a
  meeting of  Holders.   The  Registrar and  the Paying  Agent  may make
  reasonable rules for their functions.

                   SECTION 12.08.   Payments on Business Days.   If a payment
  hereunder  is scheduled to be  made on  a date that is  not a Business Day,
  payment shall be  made on  the next succeeding day  that is a Business Day,
  and no interest  shall accrue with respect to  that payment during the
  intervening period.  If  a regular Record Date is not a Business Day, such
  Record Date shall not be affected.





                                       81
<PAGE>   89





                   SECTION 12.09.  GOVERNING LAW.   THIS INDENTURE AND THE
  SECURITIES  SHALL BE GOVERNED BY, AND CONSTRUED IN  ACCORDANCE WITH,  THE
  LAWS OF THE  STATE OF  NEW YORK  BUT WITHOUT  GIVING EFFECT TO  APPLICABLE
  PRINCIPLES OF CONFLICTS OF LAW  TO THE EXTENT THAT THE  APPLICATION OF THE
  LAWS OF  ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

                   SECTION 12.10.   No Recourse Against  Others.  A director,
  officer,  employee or stockholder, as such, of  the Company or any Guarantor
  shall not have any liability for any obligations  of the Company or a
  Guarantor under the Securities,  the Guarantees or this Indenture or for  any
  claim based on, in respect of or by reason  of such  obligations or  their
  creation.   By  accepting a  Security,  each Holder  shall waive  and release
  all such liability.   The waiver and release shall  be part of the
  consideration  for the issue of the Securities.

                   SECTION  12.11   Submission  to  Jurisdiction; Appointment
  of Agent  for Service  of Process; Waiver of Immunities.

                   (a)      The  Company and each Guarantor  hereby
  irrevocably, to the fullest  extent it may do so under applicable  law,
  submits to the  jurisdiction of any New  York State or federal  court sitting
  in the Borough  of Manhattan, The City  of New York  and to the courts  of
  its own corporate  domicile with respect to all actions brought against it as
  a defendant  in respect of any suit, action or  proceeding or arbitral award
  arising out  or relating to this Indenture, the Securities  or any
  transaction contemplated  hereby or thereby (a "Proceeding"),  and
  irrevocably  accepts  for  itself and  in  respect  of  its  property,
  generally  and unconditionally,  the  jurisdiction  of the  aforesaid
  courts,  to the  fullest  extent  it may  do  so  under applicable law.  The
  Company  and each Guarantor irrevocably waives, to the fullest extent it may
  do so under applicable law, trial  by jury and any objection which it may now
  or hereafter have to  the laying of the venue of any such  Proceeding brought
  in any such court  and any claim that any  such Proceeding brought in any
  such court has been brought in an inconvenient  forum.  The Company and each
  Guarantor acknowledges that it has, by separate written  instrument,
  irrevocably  appointed  CT Corporation  System  (the "Process Agent"),  with
  an office at  1633 Broadway, New York,  New York  10019, as  its authorized
  agent to  receive on  behalf of  the Company and  each Guarantor  and its
  property  service of copies  of the  summons and complaint  and any  other
  process  which may be served in any Proceeding, and that the Process  Agent
  has accepted such appointment.  If for any reason such Process  Agent shall
  cease to be such  agent for service of process,  the Company and each
  Guarantor  shall forthwith appoint a new agent of  recognized standing for
  service of  process in the State of New York, United States  and deliver to
  the Trustee  a copy of the new agent's acceptance of  that appointment within
  30  days.  Nothing  herein shall affect  the right of  the Trustee,  any
  Paying  Agent or any  Holder to serve  process in any  other manner
  permitted by  law or  to commence  legal proceedings or  otherwise proceed
  against the Company or the Guarantors in any other court of competent
  jurisdiction.

                   (b)      Service may be  made by delivering by hand  a copy
  of such process to  the Company or the Guarantors, as the case may be, in
  care of the Process Agent at the address





                                       82
<PAGE>   90
  specified above.  The Company and the Guarantors  hereby irrevocably
  authorize and direct the  Process Agent to accept  such service on  their
  behalf.   Failure of  the Process  Agent to give  notice to  the Company  or
  the Guarantors or failure of the Company or the Guarantors to receive notice
  of such service  of process shall not affect in any way  the validity of such
  service  on the Process Agent or the Company or  the Guarantors.  As an
  alternative method  of service, the Company and the  Guarantors also
  irrevocably consent  to the service of any and all process  in any such
  proceeding by  the delivery by hand  of copies of such process to the
  Company or the Guarantors, as  the case may be,  at the applicable  address
  specified in  Section 12.05 hereof or at  the address most recently furnished
  in writing by the Company or the  Guarantors to the Trustee.  The Company and
  the Guarantors covenant and agree that they shall  take any and all
  reasonable action,  including the execution and filing of any and all
  documents,  that may be necessary to  continue the designation of the
  Process Agent specified above in full force and effect during the term of
  the Securities, and to cause the Process  Agent to continue to act as such.

                   (c)      The Company and the  Guarantors irrevocably agree
  that,  in any Proceedings  anywhere (whether for an injunction, specific
  performance or otherwise), no immunity (to  the extent that it may at any
  time  exist,  whether on  the grounds  of  sovereignty or  otherwise)  from
  such Proceedings,  from attachment (whether in aid  of execution, before
  judgment or  otherwise) of  their assets or  from execution of  judgment
  shall be claimed  by them or on their behalf or with respect to their assets,
  except  to the extent required by applicable  law, any  such immunity being
  irrevocably waived, to the  fullest extent  permitted by applicable law.
  The Company  and the Guarantors  irrevocably agree  that, where permitted  by
  applicable  law, they  and their  assets are, and  shall be,  subject to
  such Proceedings,  attachment or  execution in respect  of their obligations
  under this Indenture or the Securities.

                   SECTION  12.12.   Successors.   All  agreements  of the
  Company  in this  Indenture  and  the Securities shall  bind  its successors.
  All  agreements  of  the Trustee  in this  Indenture  shall bind  its
  successors.

                   SECTION 12.13.   Multiple Originals.   The  parties may
  sign any  number of  copies of  this Indenture.   Each signed copy  shall be
  an  original, but all  of them together  represent the same agreement.  One
  signed  copy is  enough  to prove  this Indenture.   This  Indenture  may be
  executed in  any  number of counterparts, each of which shall  be deemed an
  original, but all  such counterparts shall together constitute but one and
  the same instrument.

                   SECTION 12.14.   Table of Contents; Headings.   The table of
  contents,  cross-reference sheet and headings of the  Articles and Sections
  of  this Indenture have  been inserted for convenience  of reference only,
  are not  intended to be considered a  part hereof and shall  not modify or
  restrict any of the  terms or provisions hereof.





                                       83
<PAGE>   91
                   IN WITNESS WHEREOF, the parties have caused this Indenture
  to be duly executed as of the date first above written.


                                        COMPANY:

                                        DI INDUSTRIES, INC.


                                        By:  /s/ T. Scott O'Keefe            
                                        Name:  T. Scott O'Keefe            
                                        Title: Senior Vice President, Chief 
                                               Financial Officer & Secretary 


                                        GUARANTORS:

                                        DRILLERS, INC.


                                        By:  /s/ T. Scott O'Keefe            
                                        Name:  T. Scott O'Keefe            
                                        Title: Senior Vice President, Chief 
                                               Financial Officer & Secretary


                                        DI INTERNATIONAL, INC.


                                        By:  /s/ T. Scott O'Keefe            
                                        Name:  T. Scott O'Keefe            
                                        Title: Senior Vice President, Chief 
                                               Financial Officer & Secretary


                                        DI ENERGY, INC.


                                        By:  /s/ T. Scott O'Keefe            
                                        Name:  T. Scott O'Keefe            
                                        Title: Senior Vice President, Chief 
                                               Financial Officer & Secretary




<PAGE>   92
                                        TRUSTEE:

                                        TEXAS COMMERCE BANK NATIONAL
                                               ASSOCIATION



                                        By:  /s/ Mauri J. Cowen 
                                        Name:  Mauri J. Cowen 
                                        Title: Vice President and Trust Officer


<PAGE>   93

                                                                       EXHIBIT A



                      [FORM OF FACE OF GLOBAL SECURITY]

                             DI INDUSTRIES, INC.

No. _______             8-7/8% SENIOR NOTE DUE 2007        CUSIP No. 232909 AA 9


     THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
REFERRED TO ON THE REVERSE HEREOF.

     UNLESS THIS GLOBAL SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC" OR THE
"DEPOSITARY"), NEW YORK, NEW YORK, TO DI INDUSTRIES, INC. (THE "COMPANY") OR
ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY
CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME
AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE
TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

     TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE,
BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH
SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE
LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN
SECTION 2.06 OF THE INDENTURE REFERRED TO ON THE REVERSE HEREOF.

     THIS GLOBAL SECURITY IS EXCHANGEABLE FOR SECURITIES IN DEFINITIVE, FULLY
REGISTERED FORM, WITHOUT INTEREST COUPONS, IF (A) DTC NOTIFIES THE COMPANY THAT
IT IS UNWILLING OR UNABLE TO CONTINUE AS DEPOSITARY FOR THIS GLOBAL SECURITY OR
IF AT ANY TIME DTC CEASES TO BE A "CLEARING AGENCY" REGISTERED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED, AND A SUCCESSOR DEPOSITARY IS NOT
APPOINTED BY THE COMPANY WITHIN 90 DAYS OF SUCH NOTICE OR (B) AN EVENT OF
DEFAULT (AS HEREINAFTER DEFINED) HAS OCCURRED AND IS CONTINUING WITH RESPECT TO
THE SECURITIES.



                                      1


<PAGE>   94


     DI INDUSTRIES, INC., a Texas corporation, hereby promises to pay to CEDE &
CO., or registered assigns, the principal sum indicated on Schedule A hereof,
on July 1, 2007.

     Interest Payment Dates:  January 1 and July 1, commencing January 1, 1998.

     Record Dates:  June 15  and December 15.

     Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth in this place.

     Unless the certificate of authentication hereon has been duly executed by
the Trustee referred to on the reverse hereof by manual signature, this
Security shall not be entitled to any benefit under the Indenture or be valid
or obligatory for any purposes.

     IN WITNESS WHEREOF, DI INDUSTRIES, INC. has caused this instrument to be
duly executed under its corporate seal.

Dated:

                                    DI INDUSTRIES, INC.



                                    By:
                                       -------------------------------------
                                         Name:
                                         Title:

[Corporate Seal]

                                    By:
                                       -------------------------------------
                                         Name:
                                         Title:

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

TEXAS COMMERCE BANK NATIONAL ASSOCIATION,
     as Trustee, certifies that this is one of
     the Securities referred to in the Indenture.



By:
   --------------------------------
     Authorized Signatory



                                      2


<PAGE>   95





                       [FORM OF REVERSE SIDE OF SECURITY]

                          8-7/8% SENIOR NOTE DUE 2007


1.   Interest

     DI Industries, Inc., a Texas corporation (such corporation, and its
successors and assigns under the Indenture hereinafter referred to, being
herein called the "Company"), promises to pay interest on the principal amount
of this Security at the rate per annum shown above.  The Company will pay
interest semiannually on January 1 and July 1 of each year (an "Interest
Payment Date") commencing on January 1, 1998, until the principal amount is
paid or made available for payment.  Interest on the Securities will accrue
from the most recent date to which interest has been paid or, if no interest
has been paid, from the Issue Date.  Interest will be computed on the basis of
a 360-day year of twelve 30-day months.


2.   Method of Payment

     The Company will pay interest on the Securities (except Defaulted
Interest) to the Persons who are registered Holders of Securities at the close
of business on the June 15 or December 15 immediately preceding the Interest
Payment Date even if Securities are canceled after the Record Date and on or
before the Interest Payment Date.  Holders must surrender Securities to a
Paying Agent to collect principal payments.  The Company will pay principal,
premium, if any, and interest in money of the United States that at the time of
payment is legal tender for payment of public and private debts.  Payments in
respect of the Securities represented by a Global Security (including
principal, premium, if any, and interest) will be made by wire transfer of
immediately available funds to the accounts specified by the Depositary, but,
at the option of the Company, interest may be paid by check mailed to the
registered Holders at their registered addresses.


3.   Paying Agent and Registrar

     Initially, Texas Commerce Bank National Association, a national banking
association (the "Trustee"), will act as Paying Agent and Registrar.  The
Company may appoint and change any Paying Agent, Registrar or co-registrar
without notice.  In certain situations, the Company or any of its Subsidiaries
may act as Paying Agent, Registrar or co-registrar.


4. Indenture

     The Company issued the Securities under an Indenture dated as of June 27,
1997 (as such 

                                      3


<PAGE>   96



may be amended from time to time, the "Indenture"), among the Company, the
corporations acting as guarantors and named therein (the "Guarantors") and
Texas Commerce Bank National Association, as trustee (the "Trustee," which term
includes any successor trustee under the Indenture), to which Indenture
reference is hereby made for a statement of the respective rights, duties and
immunities thereunder of the Company, the Guarantors, the Trustee and each
Holder of the Securities and the terms upon which the Securities are, and are
to be, authenticated and delivered.  The terms of the Securities include those
stated in the Indenture and those made part of the Indenture by reference to
the Trust Indenture Act of 1939 (15 U.S.C. Section Section  77aaa-77bbbb) as in
effect on the date of the Indenture (the "Act"). Terms defined in the Indenture
and not defined herein have the meanings ascribed thereto in the Indenture. 
The Securities are subject to all such terms, and Holders are referred to the
Indenture and the Act for a statement of those terms.

     The Securities are limited to $175,000,000 aggregate principal amount at
Stated Maturity at any one time outstanding (subject to Section 2.08 of the
Indenture).  This Security is one of the Securities referred to in the
Indenture.  The Indenture imposes certain limitations on the incurrence of
additional Indebtedness by the Company and its Subsidiaries; the payment of
dividends on, and redemption of, Capital Stock of the Company and its
Subsidiaries and the redemption of Subordinated Indebtedness of the Company and
its Subsidiaries; Investments; sales of assets and Subsidiary Capital Stock;
certain transactions with Affiliates of the Company and the right of the
Company and its Subsidiaries to engage in unrelated lines of business.


5.   Optional Redemption

     Except as provided in the next paragraph, the Securities are not
redeemable prior to July 1, 2002.  At any time on or after July 1, 2002, the
Securities are redeemable at the option of the Company, in whole or in part, on
not less than 30 nor more than 60 days' notice, at the following Redemption
Prices (expressed as percentages of principal amount at Stated Maturity), if
redeemed during the 12 months beginning July 1 of the years indicated below,
plus accrued and unpaid interest (if any) thereon to the Redemption Date:



<TABLE>
<CAPTION>
                                             Redemption
         Year                                  Price
     -----------                           -------------
         <S>                                 <C>
         2002   ..........................   104.4375%
         2003   ..........................   102.9580%
         2004   ..........................   101.4792%
         2005 and thereafter .............   100.0000%
</TABLE>

     Notwithstanding the foregoing, on and prior to July 1, 2000, the Company
may redeem up to 30% of the aggregate principal amount of the Securities
originally outstanding at a redemption price of 108.875% of the principal
amount at Stated Maturity thereof, plus accrued and unpaid interest (if any)
thereon to the Redemption Date, with the net proceeds of one or 




                                      4


<PAGE>   97


more Qualified Equity Offerings of the Company; provided that at least
$120,000,000 aggregate principal amount at Stated Maturity of the Securities
shall remain outstanding immediately after the occurrence of any such
redemption; and provided, further, that such redemption shall occur not later
than 90 days after the date of the closing of any such Qualified Equity
Offering. The redemption shall be made in accordance with procedures set forth
in the Indenture.


6.   Notice of Redemption

     Notice of redemption will be mailed by first-class mail, postage prepaid,
at least 30 days but not more than 60 days before the Redemption Date to each
Holder of Securities to be redeemed at his address as it appears in the
Security Register.  Securities in denominations larger than $1,000 may be
redeemed in part but only in whole multiples of $1,000.  If less than all of
the Securities are to be redeemed at any time, the Securities to be redeemed
will be chosen by the Trustee in accordance with the Indenture.  If any
Security is redeemed subsequent to a Record Date with respect to any Interest
Payment Date specified above and on or prior to such Interest Payment Date,
then any accrued interest will be paid on such Interest Payment Date to the
Holder of the Security at the close of business on such Record Date.  If money
sufficient to pay the Redemption Price of and accrued interest on all
Securities (or portions thereof) to be redeemed on the Redemption Date is
deposited with the Paying Agent on or before the Redemption Date and certain
other conditions are satisfied, on and after such date interest ceases to
accrue on such Securities (or such portions thereof) called for redemption.


7.   Change of Control

     Upon the occurrence of a Change of Control, each Holder of Securities
shall have the right to require the Company to purchase such Holder's
Securities, in whole or in part in a principal amount at Stated Maturity that
is an integral multiple of $1,000, pursuant to a Change of Control Offer, at a
purchase price in cash equal to 101% of the principal amount at Stated Maturity
thereof on any Change of Control Payment Date, plus accrued and unpaid
interest, if any, to the Change of Control Payment Date.

     Within 30 calendar days following any Change of Control, the Company shall
send, or cause to be sent, by first class mail, postage prepaid, a notice
regarding the Change of Control Offer to each Holder of Securities.  The Holder
of this Security may elect to have this Security or a portion hereof in an
authorized denomination purchased by completing the form entitled "Option of
Holder to Elect Purchase" appearing below and tendering this Security pursuant
to the Change of Control Offer.  Unless the Company defaults in the payment of
the Change of Control Purchase Price with respect thereto, all Securities or
portions thereof accepted for payment pursuant to the Change of Control Offer
will cease to accrue interest from and after the Change of Control Payment
Date.



                                      5


<PAGE>   98



8.   Repurchase at the Option of Holders upon Asset Sale

     Subject to the limitations set forth in the next following paragraph, if
at any time the Company or any Subsidiary engages in any Asset Sale, as a
result of which the aggregate amount of Excess Proceeds exceeds $15,000,000,
the Company shall, within 30 calendar days of the date the amount of Excess
Proceeds exceeds $15,000,000, or at any time after receipt of Excess Proceeds
but prior to there being $15,000,000 of Excess Proceeds, the Company may, at
its option, use the then-existing Excess Proceeds to make an offer to purchase
from all Holders, on a pro rata basis, Securities in an aggregate principal
amount at Stated Maturity equal to the maximum principal amount that may be
purchased out of the then-existing Excess Proceeds, at a purchase price in cash
equal to 100% of the principal amount at Stated Maturity thereof, plus accrued
and unpaid interest, if any, to the Asset Sale Offer Purchase Date.  Upon
completion of an Asset Sale Offer (including payment of the Asset Sale Offer
Purchase Price for accepted Securities), any surplus Excess Proceeds that were
the subject of such offer shall cease to be Excess Proceeds, and the Company
may then use such amounts for general corporate purposes.

     Within 30 calendar days of the date the amount of Excess Proceeds exceeds
$15,000,000, the Company shall send, or cause to be sent, by first class mail,
postage prepaid, a notice regarding the Asset Sale Offer to each Holder of
Securities.  The Holder of this Security may elect to have this Security or a
portion hereof in an authorized denomination purchased by completing the form
entitled "Option of Holder to Elect Purchase" appearing below and tendering
this Security pursuant to the Asset Sale Offer.  Unless the Company defaults in
the payment of the Asset Sale Offer Purchase Price with respect thereto, all
Securities or portions thereof selected for payment pursuant to the Asset Sale
Offer will cease to accrue interest from and after the Asset Sale Offer
Purchase Date.


9.   The Global Security

     So long as this Global Security is registered in the name of the
Depositary or its nominee, members of, or participants in, the Depositary
("Agent Members") shall have no rights under the Indenture with respect to this
Global Security held on their behalf by the Depositary or the Trustee as its
custodian, and the Depositary may be treated by the Company, the Guarantors,
the Trustee and any agent of the Company, the Guarantors or the Trustee as the
absolute owner of this Global Security for all purposes.  Notwithstanding the
foregoing, nothing herein shall (i) prevent the Company, the Guarantors, the
Trustee or any agent of the Company, the Guarantors or the Trustee from giving
effect to any written certification, proxy or other authorization furnished by
the Depositary or (ii) impair, as between the Depositary and its Agent Members,
the operation of customary practices governing the exercise of the rights of a
Holder of Securities.

     The Holder of this Global Security may grant proxies and otherwise
authorize any Person, including Agent Members and Persons that may hold
interests in this Global Note through Agent Members, to take any action which a
Holder of Securities is entitled to take under the Indenture or the Securities.

     Whenever, as a result of an optional redemption of Securities by the
Company, a 

                                      6


<PAGE>   99

Change of Control Offer, an Asset Sale Offer or an exchange for Certificated
Securities, this Global Security is redeemed, repurchased or exchanged or
substituted in part, this Global Security shall be surrendered by the Holder
thereof to the Trustee who shall cause an adjustment to be made to Schedule A
hereof so that the principal amount of this Global Security will be equal to
the portion not redeemed, repurchased or exchanged and shall thereafter return
this Global Security to such Holder; provided that this Global Security shall
be in a principal amount at Stated Maturity of $1,000 or an integral multiple
of $1,000.


10.  Transfer and Exchange

     The Holder of this Global Security shall, by its acceptance of this Global
Security, agree that transfers of beneficial interests in this Global Security
may be effected only through a book entry system maintained by such Holder (or
its agent), and that ownership of a beneficial interest in the Securities
represented thereby shall be required to be reflected in book entry form.

     Transfers of this Global Security shall be limited to transfers in whole,
and not in part, to the Depositary, its successors and their respective
nominees.  Interests of beneficial owners in this Global Security may be
transferred in accordance with the rules and procedures of the Depositary (or
its successors).

     This Global Security will be exchanged by the Company for one or more
Certificated Securities if (a) the Depositary (i) has notified the Company that
it is unwilling or unable to continue as, or ceases to be, a "Clearing Agency"
registered under Section 17A of the Exchange Act and (ii) a successor to the
Depositary registered as a "Clearing Agency" under Section 17A of the Exchange
Act is not appointed by the Company within 90 calendar days or (b) the
Depositary is at any time unwilling or unable to continue as Depositary and a
successor to the Depositary is not able to be appointed by the Company within
90 calendar days.  If an Event of Default occurs and is continuing, the Company
shall, at the request of the Holder hereof, exchange all or a part of this
Global Security for one or more Certificated Securities; provided that the
principal amount at Stated Maturity of each of such Certificated Securities and
this Global Security, after such exchange, shall be $1,000 or an integral
multiple thereof.  Whenever this Global Security is exchanged as a whole for
one or more Certificated Securities, it shall be surrendered by the Holder to
the Trustee for cancellation.  Whenever this Global Security is exchanged in
part for one or more Certificated Securities, it shall be surrendered by the
Holder to the Trustee and the Trustee shall make the appropriate notations
thereon pursuant to Section 2.05 of the Indenture. Interests in this Global
Security may not be exchanged for Certificated Securities other than as provided
in this paragraph.


                                      7


<PAGE>   100



11.  Persons Deemed Owners

     The registered Holder of this Security may be treated as the owner of it
for all purposes.

12. Unclaimed Money

     If money for the payment of principal or interest remains unclaimed for
two years, the Trustee or Paying Agent shall pay the money back to the Company
at its written request unless an abandoned property law designates another
Person.  After any such payment, Holders entitled to the money must look only
to the Company and not to the Trustee for payment.

13. Discharge and Defeasance

     Subject to certain conditions, the Company at any time may terminate some
or all of its Obligations and the Guarantors' Obligations under the Securities,
the Guarantees and the Indenture if the Company deposits with the Trustee money
or U.S. Government Obligations for the payment of principal, premium and
interest on the Securities to redemption or Maturity, as the case may be.


14. Amendment, Waiver

     Subject to certain exceptions set forth in the Indenture, (i) the
Indenture or the Securities may be amended with the written consent of the
Holders of at least a majority in outstanding principal amount at Stated
Maturity of the Securities and (ii) any default or noncompliance with any
provision may be waived with the written consent of the Holders of a majority
in outstanding principal amount at Stated Maturity outstanding of the
Securities.  Subject to certain exceptions set forth in the Indenture, without
the consent of any Holder, the Company, the Guarantors and the Trustee may
amend the Indenture or the Securities (a) to evidence the succession of another
Person to the Company and the Guarantors and the assumption by such successor
of the covenants and Obligations of the Company under the Indenture and
contained in the Securities and of the Guarantors contained in the Indenture
and the Guarantees, (b) to add to the covenants of the Company, for the benefit
of the Holders, or to surrender any right or power conferred upon the Company
or the Guarantors by the Indenture, (c) to add any additional Events of
Default, (d) to provide for uncertificated Securities in addition to or in
place of Certificated Securities, (e) to evidence and provide for the
acceptance of appointment under the Indenture by the successor Trustee, (f) to
secure the Securities and/or the Guarantees, (g) to cure any ambiguity, to
correct or supplement any provision in the Indenture which may be inconsistent
with any other provision therein or to add any other provision with respect to
matters or questions arising under the Indenture, provided that such actions
will not adversely affect the interests of the Holders in any material respect
or (h) to add or release any Guarantor pursuant to the terms of the Indenture.
Certain provisions of the Securities and the Indenture may not be amended or
waived without the consent of each Holder affected thereby.

15.  Defaults and Remedies

     Under the Indenture, Events of Default include in summary form (i) default
in the payment 



                                      8

<PAGE>   101
of principal of (or premium, if any, on) the Securities when due; (iii) 
failure to comply with certain of the covenants in the Indenture, including the
Change of Control covenant, the Asset Sale covenant and the Restrictive Payments
covenant; (iv) failure to perform any other covenant of the Company or any
Guarantor in the Indenture, continued for 30 days after written notice as
provided in the Indenture; (v) Indebtedness of the Company or any Subsidiary is
not paid when due within the applicable grace period, or is accelerated and, in
either case, the principal amount of such unpaid Indebtedness exceeds
$10,000,000; (vi) one or more final judgments or orders by a court of competent
jurisdiction are entered against the Company or any Subsidiary in an uninsured
or unindemnified aggregate amount in excess of $5,000,000 and such judgments or
orders are not discharged, waived, appealed, stayed, satisfied or bonded for a
period of 60 consecutive days; (vii) certain events of bankruptcy, insolvency or
reorganization; or (viii) a Guarantee ceases to be in full force and effect
(other than in accordance with the terms of the Indenture and such Guarantee) or
a Guarantor denies or disaffirms its obligations under its Guarantee.

     Holders may not enforce the Indenture or the Securities except as provided
in the Indenture.  The Trustee may refuse to enforce the Indenture or the
Securities unless it receives reasonable indemnity or security.  Subject to
certain limitations, Holders of a majority in principal amount at Stated
Maturity of the Securities may direct the Trustee in its exercise of any trust
or power.  The Trustee may withhold from Holders notice of any continuing
Default (except a Default in payment of principal or interest) if it determines
that withholding notice is in the interest of the Holders.  The Holders of a
majority in principal amount at Stated Maturity of the outstanding Securities,
by written notice to the Company and the Trustee, may rescind any declaration
of acceleration and its consequences if the rescission would not conflict with
any judgment or decree, and if all Events of Default have been cured or waived
except nonpayment of principal and interest that has become due solely because
of the acceleration.


16. Trustee Dealings with the Company

     Subject to certain limitations imposed by the Trust Indenture Act,  the
Trustee under the Indenture, in its individual or any other capacity, may
become the owner or pledgee of Securities and may otherwise deal with and
collect obligations owed to it by the Company or its Affiliates and may
otherwise deal with the Company or its Affiliates with the same rights it would
have if it were not Trustee.


17. No Recourse Against Others

     A director, officer, employee or stockholder, as such, of the Company or
any Guarantor shall not have any liability for any obligations of the Company
or a Guarantor under the Securities, the Guarantees or the Indenture or for any
claim based on, in respect of or by reason of such obligations or their
creation.  By accepting a Security, each Holder waives and releases all such
liability.  The waiver and release are part of the consideration for the issue
of the Securities.




                                      9


<PAGE>   102

18.  Governing Law

     THIS SECURITY SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
LAWS OF THE STATE OF NEW YORK BUT WITHOUT GIVING EFFECT TO APPLICABLE
PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS
OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.


19.  Abbreviations

     Customary abbreviations may be used in the name of a Holder or an
assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the
entireties), JT TEN (=joint tenants with rights of survivorship and not as
tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors
Act).


20.  CUSIP Numbers

     Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures the Company has caused CUSIP numbers to be
printed on the Securities and has directed the Trustee to use CUSIP numbers in
notices of redemption as a convenience to Holders.  No representation is made
as to the accuracy of such numbers either as printed on the Securities or as
contained in any notice of redemption and reliance may be placed only on the
other identification numbers placed thereon.

     The Company will furnish to any Holder upon written request and without
charge to the Holder a copy of the Indenture which has in it the text of this
Security.



                                     10


<PAGE>   103


                               SECURITY GUARANTEE

     Subject to the limitations set forth in the Indenture, the Guarantors (as
defined in the Indenture referred to in this Security and each hereinafter
referred to as a "Guarantor," which term includes any successor or additional
Guarantor under the Indenture) have jointly and severally, irrevocably and
unconditionally guaranteed (a) the due and punctual payment of the principal
(and premium, if any) of and interest on the Securities, whether at Stated
Maturity, by acceleration, call for redemption, upon a Change of Control Offer,
Asset Sale Offer, purchase or otherwise, (b) the due and punctual payment of
interest on the overdue principal of and interest on the Securities, if any, to
the extent lawful, (c) the due and punctual performance of all other
Obligations of the Company and the Guarantors to the Holders under the
Indenture and the Notes and (d) in case of any extension of time of payment or
renewal of any Securities or any of such other Obligations, the same will be
promptly paid in full when due or performed in accordance with the terms of the
extension or renewal, whether at Stated Maturity, by acceleration, call for
redemption, upon a Change of Control Offer, Asset Sale Offer, purchase or
otherwise.  Capitalized terms used herein shall have the same meanings assigned
to them in the Indenture unless otherwise indicated.

     Payment on each Security is guaranteed jointly and severally, by the
Guarantors pursuant to Article 11 of the Indenture and reference is made to
such Indenture for the precise terms of the Guarantees.

     The Obligations of each Guarantor are limited to the maximum amount as
will, after giving effect to such maximum amount and all other contingent and
fixed liabilities of such Guarantor, and after giving effect to any collections
from or payments made by or on behalf of any other Guarantor in respect of the
Obligations of such other Guarantor under its Guarantee or pursuant to its
contribution Obligations under the Indenture, result in the Obligations of such
Guarantor under its Guarantee not constituting a fraudulent conveyance or
fraudulent transfer under federal or state law or not otherwise being void,
voidable or unenforceable under any similar other bankruptcy, receivership,
insolvency, liquidation or other similar legislation or legal principles under
applicable foreign law.  Each Guarantor that makes a payment or distribution
under a Guarantee shall be entitled to a contribution from each other Company
in a pro rata amount based on the Adjusted Net Assets of each Guarantor.

     Certain of the Guarantors may be released from their Guarantees upon the
terms and subject to the conditions provided in the Indenture.



                                     11


<PAGE>   104



     The Guarantee shall be binding upon each Guarantor and its successors and
assigns and shall inure to the benefit of the Trustee and the Holders and, in
the event of any transfer or assignment of rights by any Holder or the Trustee,
the rights and privileges herein conferred upon that party shall automatically
extend to and be vested in such transferee or assignee, all subject to the
terms and conditions hereof and in the Indenture.

                              DRILLERS, INC.         
                                                     
                                                     
                                                     
                              By:                    
                                 --------------------------------------
                                                     

                              DI INTERNATIONAL, INC. 
                                                     
                                                     
                                                     
                              By:                    
                                 ---------------------------------------

                                                     
                              DI ENERGY, INC.        
                                                     
                                                     
                                                     
                              By:
                                 ---------------------------------------



                                     12


<PAGE>   105




                                ASSIGNMENT FORM

To assign this Security, fill in the form below:

I or we assign and transfer this Security to


- --------------------------------------------------------------------------------
     (Print or type assignee's name, address and zip code)


- --------------------------------------------------------------------------------
     (Insert assignee's social security or tax I.D. No.)


and irrevocably appoint _______________ agent to transfer this Security on the 
books of the Company.  The agent may substitute another to act for him.



Dated:                  Your Signature:
       ----------------                -----------------------------------------


- --------------------------------------------------------------------------------
Sign exactly as your name appears on the other side of this Security.


Signature Guarantee:


- -----------------------------
Signature must be guaranteed


- --------------------------------------------------------------------------------
Notice: Signature(s) must be guaranteed by an institution which is a participant
in the Securities Transfer Agent Medallion Program ("STAMP") or similar program.



                                      1


<PAGE>   106




                       OPTION OF HOLDER TO ELECT PURCHASE

     If you want to elect to have this Security purchased by the Company
pursuant to Section 4.07 or Section 4.09 of the Indenture, check the
appropriate box:

                               Section 4.07  [  ]

                               Section 4.09  [  ]

     If you want to elect to have only part of this Security purchased by the
Company pursuant to Section 4.07 or Section 4.09 of the Indenture, state the
amount in principal amount (must be an integral of $1,000):  $_______________



Dated:                  Your Signature:
      -----------------                -----------------------------------------
                                       (Sign exactly as your name appears on
                                       the other side of this Security.)

Signature Guarantee:
                      --------------------------------
                      (Signature must be guaranteed)


- --------------------------------------------------------------------------------
Notice: Signature(s) must be guaranteed by an institution which is a participant
in the Securities Transfer Agent Medallion Program ("STAMP") or similar program.




                                      2


<PAGE>   107




                                   SCHEDULE A

             SCHEDULE OF INCREASES OR DECREASES IN PRINCIPAL AMOUNT

     The initial principal amount at Maturity of this Global Security shall be
$175,000,000.  The following increases or decreases in this Global Security
have been made:


<TABLE>
<CAPTION>
                                                                                 Signature of
                                                           Total Principal       authorized
                                                           amount of this        signatory of
Date of        Amount of decrease    Amount of increase    Global Security       Trustee or
Increase/      in Principal          in Principal Amount   following such        Securities
Decrease       Amount at Maturity    at Maturity           Decrease/ Increase    Custodian
- --------       --------------------  --------------------  --------------------  -------------
<S>            <C>                   <C>                   <C>                   <C>
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
_____________  _____________         _____________         _____________         _____________
</TABLE>




                                      3


<PAGE>   108

                                                                       EXHIBIT B



                   [FORM OF FACE OF CERTIFICATED SECURITY]

                             DI INDUSTRIES, INC.

No._______               8-7/8% SENIOR NOTE DUE 2007       CUSIP No. 232909 AA 9



     DI INDUSTRIES, INC., a Texas corporation, hereby promises to pay to
_________________, or registered assigns, the principal sum of _______________
on July 1, 2007.

     Interest Payment Dates:  January 1 and July 1, commencing January 1, 1998.

     Record Dates:  June 15 and December 15.

     Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth in this place.

     Unless the certificate of authentication hereon has been duly executed by
the Trustee referred to on the reverse hereof by manual signature, this
Security shall not be entitled to any benefit under the Indenture or be valid
or obligatory for any purposes.

     IN WITNESS WHEREOF, DI INDUSTRIES, INC. has caused this instrument to be
duly executed under its corporate seal.

Dated:
      ----------------------
                                    DI INDUSTRIES, INC.



                                    By:
                                       --------------------------------
                                         Name:
                                         Title:

[Corporate Seal]

                                    By:
                                       --------------------------------
                                         Name:
                                         Title:

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

TEXAS COMMERCE BANK NATIONAL ASSOCIATION,
as Trustee, certifies that this is one of
     the Securities referred to in the Indenture.




By:
   ----------------------------------
     Authorized Signatory



                                      1


<PAGE>   109




                       [FORM OF REVERSE SIDE OF SECURITY]


                          8-7/8% Senior Note Due 2007



1.   Interest

     DI Industries, Inc., a Texas corporation (such corporation, and its
successors and assigns under the Indenture hereinafter referred to, being
herein called the "Company"), promises to pay interest on the principal
amount of this Security at the rate per annum shown above.  The Company will
pay interest semiannually on January 1 and July 1 of each year (an "Interest
Payment Date") commencing on January 1, 1998, until the principal amount is
paid or made available for payment.  Interest on the Securities will accrue
from the most recent date to which interest has been paid or, if no interest
has been paid, from the Issue Date.  Interest will be computed on the basis
of a 360-day year of twelve 30-day months.

2.   Method of Payment

     The Company will pay interest on the Securities (except Defaulted
Interest) to the Persons who are registered Holders of Securities at the
close of business on the June 15 or December 15 immediately preceding the
Interest Payment Date even if Securities are canceled after the Record Date
and on or before the Interest Payment Date.  Holders must surrender
Securities to a Paying Agent to collect principal payments.  The Company
will pay principal, premium, if any, and interest in money of the United
States that at the time of payment is legal tender for payment of public and
private debts.  Payments in respect of the Securities represented by a
Global Security (including principal, premium, if any, and interest) will be
made by wire transfer of immediately available funds to the accounts
specified by The Depository Trust Company, but, at the option of the
Company, interest may be paid by check mailed to the registered Holders at
their registered addresses.


3.   Paying Agent and Registrar

     Initially, Texas Commerce Bank National Association, a national banking
association (the "Trustee"), will act as Paying Agent and Registrar.  The
Company may appoint and change any Paying Agent, Registrar or co-registrar
without notice.  In certain circumstances, the Company or any of its
Subsidiaries may act as Paying Agent, Registrar or co-registrar.


4.   Indenture

     The Company issued the Securities under an Indenture dated as of June
27, 1997 (as such may be amended from time to time, the "Indenture"), among
the Company, the corporations acting as guarantors and named therein (the
"Guarantors") and the Texas Commerce Bank National Association, as trustee (the
"Trustee", which term includes any successor trustee under the Indenture), to
which 
                                        

                                      2


<PAGE>   110



Indenture reference is hereby made for a statement of the respective rights,
duties and immunities thereunder of the Company, the Guarantors, the Trustee and
each Holder of the Securities and the terms upon which the Securities are, and
are to be, authenticated and delivered.  The terms of the Securities include
those stated in the Indenture and those made part of the Indenture by reference
to the Trust Indenture Act of 1939 (15 U.S.C. Section Section  77aaa-77bbbb) as
in effect on the date of the Indenture (the "Act").  Terms defined in the
Indenture and not defined herein have the meanings ascribed thereto in the
Indenture.  The Securities are subject to all such terms, and Holders are
referred to the Indenture and the Act for a statement of those terms.

     The Securities are limited to $175,000,000 aggregate principal amount
at Stated Maturity at any one time outstanding (subject to Section 2.08 of
the Indenture).  This Security is one of the Securities referred to in the
Indenture.  The Indenture imposes certain limitations on the incurrence of
additional Indebtedness by the Company and its Subsidiaries; the payment of
dividends on, and redemption of, Capital Stock of the Company and its
Subsidiaries and the redemption of Subordinated Indebtedness of the Company
and its Subsidiaries; Investments; sales of assets and Subsidiary Capital
Stock; certain transactions with Affiliates of the Company and the right of
the Company and its Subsidiaries to engage in unrelated lines of business.


5.   Optional Redemption

     Except as provided in the next paragraph, the Securities are not
redeemable prior to July 1, 2002.  At any time on or after July 1, 2002, the
Securities are redeemable at the option of the Company, in whole or in part,
on not less than 30 nor more than 60 days' notice, at the following
Redemption Prices (expressed as percentages of principal amount at Stated
Maturity), if redeemed during the 12 months beginning July 1 of the years
indicated below, plus accrued and unpaid interest (if any) thereon to the
Redemption Date:


<TABLE>
<CAPTION>
                                               Redemption
              Year                               Price   
     ----------------------                    ----------
     <S>                                       <C>       
                                                         
     2002 ....................................  104.4375%
     2003 ....................................  102.9580%
     2004 ....................................  101.4792%
     2005 and thereafter .....................  100.0000%
</TABLE>



     Notwithstanding the foregoing, on and prior to July 1, 2000, the
Company may redeem up to 30% of the aggregate principal amount at Stated
Maturity of the Securities originally outstanding at a redemption price of
108.875% of the principal amount at Stated Maturity thereof, plus accrued
and unpaid interest (if any) thereon to the Redemption Date, with the net
proceeds of one or more Qualified Equity Offerings of the Company; provided
that at least $120,000,000 aggregate principal amount of the Securities shall
remain outstanding immediately after the occurrence of any such redemption; and
provided, further, that such redemption shall occur not later than 90 days
after the date of the closing of any such Qualified Equity Offering. The
redemption shall be made in accordance with procedures set forth in the
Indenture.



                                      3

<PAGE>   111





6.   Notice of Redemption

     Notice of redemption will be mailed by first-class mail, postage
prepaid, at least 30 days but not more than 60 days before the Redemption
Date to each Holder of Securities to be redeemed at his address as it
appears in the Security Register.  Securities in denominations larger than
$1,000 may be redeemed in part but only in whole multiples of $1,000.  If
less than all of the Securities are to be redeemed at any time, the
Securities to be redeemed will be chosen by the Trustee in accordance with
the Indenture.  If any Security is redeemed subsequent to a Record Date with
respect to any Interest Payment Date specified above and on or prior to such
Interest Payment Date, then any accrued interest will be paid on such
Interest Payment Date to the Holder of the Security at the close of business
on such Record Date.  If money sufficient to pay the Redemption Price of and
accrued interest on all Securities (or portions thereof) to be redeemed on
the Redemption Date is deposited with the Paying Agent on or before the
Redemption Date and certain other conditions are satisfied, on and after
such date interest ceases to accrue on such Securities (or such portions
thereof) called for redemption.


7.   Change of Control

     Upon the occurrence of a Change of Control, each Holder of Securities
shall have the right to require the Company to purchase such Holder's
Securities, in whole or in part in a principal amount at Stated Maturity
that is an integral multiple of $1,000, pursuant to a Change of Control
Offer, at a purchase price in cash equal to 101% of the principal amount at
Stated Maturity thereof on any Change of Control Payment Date, plus accrued
and unpaid interest, if any, to the Change of Control Payment Date.

     Within 30 calendar days following any Change of Control, the Company
shall send, or cause to be sent, by first class mail, postage prepaid, a
notice regarding the Change of Control Offer to each Holder of Securities.
The Holder of this Security may elect to have this Security or a portion
hereof in an authorized denomination purchased by completing the form
entitled "Option of Holder to Elect Purchase" appearing below and tendering
this Security pursuant to the Change of Control Offer.  Unless the Company
defaults in the payment of the Change of Control Purchase Price with respect
thereto, all Securities or portions thereof accepted for payment pursuant to
the Change of Control Offer will cease to accrue interest from and after the
Change of Control Payment Date.


8.   Repurchase at the Option of Holders upon Asset Sale.

     Subject to the limitations set forth in the next following paragraph,
if at any time the Company or any Subsidiary engages in any Asset Sale, as a
result of which the aggregate amount of Excess Proceeds exceeds $15,000,000,
the Company shall, within 30 calendar days of the date the amount of Excess
Proceeds exceeds $15,000,000, or at any time after receipt of Excess
Proceeds but prior to there being $15,000,000 of Excess Proceeds, the
Company may, at its option, use the then-existing Excess Proceeds to make an
offer to purchase from all Holders, on a pro rata basis, 


                                      4


<PAGE>   112




Securities in an aggregate principal amount equal to the maximum principal
amount that may be purchased out of the then-existing Excess Proceeds, at a
purchase price in cash equal to 100% of the principal amount at Stated Maturity
thereof, plus accrued and unpaid interest, if any, to the Asset Sale Offer
Purchase Date. Upon completion of an Asset Sale Offer (including payment of the
Asset Sale Offer Purchase Price for accepted Securities), any surplus Excess
Proceeds that were the subject of such offer shall cease to be Excess Proceeds,
and the Company may then use such amounts for general corporate purposes.

     Within 30 calendar days of the date the amount of Excess Proceeds
exceeds $15,000,000, the Company shall send, or cause to be sent, by first
class mail, postage prepaid, a notice regarding the Asset Sale Offer to each
Holder of Securities.  The Holder of this Security may elect to have this
Security or a portion hereof in an authorized denomination purchased by
completing the form entitled "Option of Holder to Elect Purchase" appearing
below and tendering this Security pursuant to the Asset Sale Offer.  Unless
the Company defaults in the payment of the Asset Sale Offer Purchase Price
with respect thereto, all Securities or portions thereof selected for
payment pursuant to the Asset Sale Offer will cease to accrue interest from
and after the Asset Sale Offer Purchase Date.


9.   Transfer and Exchange

     A Holder may transfer a Security only upon the surrender of such
Security for registration of transfer.  No such transfer shall be effected
until, and such transferee shall succeed to the rights of a Holder only
upon, final acceptance and registration of the transfer in the Security
Register by the Registrar.  When Securities are presented to the Registrar
with a request to register the transfer of, or to exchange, such Securities,
the Registrar shall register the transfer or make such exchange as requested
if its requirements for such transactions and any applicable requirements
hereunder are satisfied.

     No service charge shall be made for any registration of transfer or
exchange of Securities, but the Company may require payment of a sum
sufficient to cover any tax or other governmental charge that may be imposed
in connection with any registration of transfer of Securities.

     
10.  Persons Deemed Owners

     The registered Holder of this Security may be treated as the owner of
it for all purposes.

11. Unclaimed Money

     If money for the payment of principal or interest remains unclaimed for
two years, the Trustee or Paying Agent shall pay the money back to the
Company at its written request unless an abandoned property law designates
another Person.  After any such payment, Holders entitled to the money must
look only to the Company and not to the Trustee for payment.






                                      5


<PAGE>   113




12.  Discharge and Defeasance

     Subject to certain conditions, the Company at any time may terminate
some or all of its Obligations and the Guarantors' Obligations under the
Securities, the Guarantees and the Indenture if the Company deposits with
the Trustee money or U.S. Government Obligations for the payment of
principal, premium and interest on the Securities to redemption or Maturity,
as the case may be.


13.  Amendment, Waiver

     Subject to certain exceptions set forth in the Indenture, (i) the
Indenture or the Securities may be amended with the written consent of the
Holders of at least a majority in outstanding principal amount at Stated
Maturity of the Securities and (ii) any default or noncompliance with any
provision may be waived with the written consent of the Holders of a
majority in outstanding principal amount at Stated Maturity outstanding of
the Securities.  Subject to certain exceptions set forth in the Indenture,
without the consent of any Holder, the Company, the Guarantors and the
Trustee may amend the Indenture or the Securities (a) to evidence the
succession of another Person to the Company and the Guarantors and the
assumption by such successor of the covenants and Obligations of the Company
under the Indenture and contained in the Securities and of the Guarantors
contained in the Indenture and the Guarantees, (b) to add to the covenants
of the Company, for the benefit of the Holders, or to surrender any right or
power conferred upon the Company or the Guarantors by the Indenture, (c) to
add any additional Events of Default, (d) to provide for uncertificated
Securities in addition to or in place of certificated Securities, (e) to
evidence and provide for the acceptance of appointment under the Indenture
by the successor Trustee, (f) to secure the Securities and/or the
Guarantees, (g) to cure any ambiguity, to correct or supplement any
provision in the Indenture which may be inconsistent with any other
provision therein or to add any other provision with respect to matters or
questions arising under the Indenture, provided that such actions will not
adversely affect the interests of the Holders in any material respect or (h)
to add or release any Guarantor pursuant to the terms of the Indenture.
Certain provisions of the Securities and the Indenture may not be amended or
waived without the consent of each Holder affected thereby.




                                      6


<PAGE>   114





14.  Defaults and Remedies

     Under the Indenture, Events of Default include in summary form (i)
default in the payment of interest on the Securities when due, continued for
30 days; (ii) default in the payment of principal of (or premium, if any,
on) the Securities when due; (iii) failure to comply with certain of the
covenants in the Indenture, including the Change of Control covenant, the
Asset Sale covenant and the Restrictive Payments covenant; (iv) failure to
perform any other covenant of the Company or any Guarantor in the Indenture,
continued for 30 days after written notice as provided in the Indenture; (v)
Indebtedness of the Company or any Subsidiary is not paid when due within
the applicable grace period, or is accelerated and, in either case, the
principal amount of such unpaid Indebtedness exceeds $10,000,000; (vi) one
or more final judgments or orders by a court of competent jurisdiction are
entered against the Company or any Subsidiary in an uninsured or
unindemnified aggregate amount in excess of $5,000,000 and such judgments or
orders are not discharged, waived, appealed, stayed, satisfied or bonded for
a period of 60 consecutive days; (vii) certain events of bankruptcy,
insolvency or reorganization; or (viii) a Guarantee ceases to be in full
force and effect (other than in accordance with the terms of the Indenture
and such Guarantee) or a Guarantor denies or disaffirms its obligations
under its Guarantee.

     Holders may not enforce the Indenture or the Securities except as
provided in the Indenture.  The Trustee may refuse to enforce the Indenture
or the Securities unless it receives reasonable indemnity or security.
Subject to certain limitations, Holders of a majority in principal amount at
Stated Maturity of the Securities may direct the Trustee in its exercise of
any trust or power.  The Trustee may withhold from Holders notice of any
continuing Default (except a Default in payment of principal or interest) if
it determines that withholding notice is in the interest of the Holders.
The Holders of a majority in principal amount at Stated Maturity of the
outstanding Securities, by written notice to the Company and the Trustee,
may rescind any declaration of acceleration and its consequences if the
rescission would not conflict with any judgment or decree, and if all Events
of Default have been cured or waived except nonpayment of principal and
interest that has become due solely because of the acceleration.


15.  Trustee Dealings with the Company

     Subject to certain limitations imposed by the Trust Indenture Act,  the
Trustee under the Indenture, in its individual or any other capacity, may
become the owner or pledgee of Securities and may otherwise deal with and
collect obligations owed to it by the Company or its Affiliates and may
otherwise deal with the Company or its Affiliates with the same rights it
would have if it were not Trustee.




                                      7


<PAGE>   115





16.  No Recourse Against Others

     A director, officer, employee or stockholder, as such, of the Company
or any Guarantor shall not have any liability for any obligations of the
Company or a Guarantor under the Securities, the Guarantees or the Indenture
or for any claim based on, in respect of or by reason of such obligations or
their creation.  By accepting a Security, each Holder waives and releases
all such liability.  The waiver and release are part of the consideration
for the issue of the Securities.


17.  Governing Law

     THIS SECURITY SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH,
THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT GIVING EFFECT TO APPLICABLE
PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE
LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.


18.  Abbreviations

     Customary abbreviations may be used in the name of a Holder or an
assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the
entireties), JT TEN (=joint tenants with rights of survivorship and not as
tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors
Act).


19.  CUSIP Numbers

     Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures the Company has caused CUSIP numbers to
be printed on the Securities and has directed the Trustee to use CUSIP
numbers in notices of redemption as a convenience to Holders.  No
representation is made as to the accuracy of such numbers either as printed
on the Securities or as contained in any notice of redemption and reliance
may be placed only on the other identification numbers placed thereon.


     The Company will furnish to any Holder upon written request and without
charge to the Holder a copy of the Indenture which has in it the text of
this Security.





                                      8


<PAGE>   116




                             SECURITY GUARANTEE

     Subject to the limitations set forth in the Indenture, the Guarantors
(as defined in the Indenture referred to in this Security and each
hereinafter referred to as a "Guarantor," which term includes any successor
or additional Guarantor under the Indenture) have jointly and severally,
irrevocably and unconditionally guaranteed (a) the due and punctual payment
of the principal (and premium, if any) of and interest on the Securities,
whether at Stated Maturity, by acceleration, call for redemption, upon a
Change of Control Offer, Asset Sale Offer, purchase or otherwise, (b) the
due and punctual payment of interest on the overdue principal of and
interest on the Securities, if any, to the extent lawful, (c) the due and
punctual performance of all other Obligations of the Company and the
Guarantors to the Holders under the Indenture and the Notes and (d) in case
of any extension of time of payment or renewal of any Securities or any of
such other Obligations, the same will be promptly paid in full when due or
performed in accordance with the terms of the extension or renewal, whether
at Stated Maturity, by acceleration, call for redemption, upon a Change of
Control Offer, Asset Sale Offer, purchase or otherwise.  Capitalized terms
used herein shall have the same meanings assigned to them in the Indenture
unless otherwise indicated.

     Payment on each Security is guaranteed jointly and severally, by the
Guarantors pursuant to Article 11 of the Indenture and reference is made to
such Indenture for the precise terms of the Guarantees.

     The obligations of each Guarantor are limited to the maximum amount as
will, after giving effect to such maximum amount and all other contingent
and fixed liabilities of such Guarantor, and after giving effect to any
collections from or payments made by or on behalf of any other Guarantor in
respect of the Obligations of such other Guarantor under its Guarantee or
pursuant to its contribution Obligations under the Indenture, result in the
Obligations of such Guarantor under its Guarantee not constituting a
fraudulent conveyance or fraudulent conveyance or fraudulent transfer under
federal or state law or not otherwise being void, voidable or unenforceable
under any similar other bankruptcy, receivership, insolvency, liquidation or
other similar legislation or legal principles under applicable foreign law.
Each Guarantor that makes a payment or distribution under a Guarantee shall
be entitled to a contribution from each other Company in a pro rata amount
based on the Adjusted Net Assets of each Guarantor.

     Certain of the Guarantors may be released from their Guarantees upon
the terms and subject to the conditions provided in the Indenture.



                                      9


<PAGE>   117





     The Guarantee shall be binding upon each Guarantor and its successors
and assigns and shall inure to the benefit of the Trustee and the Holders
and, in the event of any transfer or assignment of rights by any Holder or
the Trustee, the rights and privileges herein conferred upon that party
shall automatically extend to and be vested in such transferee or assignee,
all subject to the terms and conditions hereof and in the Indenture.

                                DRILLERS, INC.          
                                                        
                                                        
                                                        
                                By:                     
                                   ----------------------------------
                                                        
                                DI INTERNATIONAL, INC.  
                                                        
                                                        
                                                        
                                By:                     
                                   ----------------------------------
                                                        
                                                        
                                DI ENERGY, INC.         
                                                        
                                                        
                                                        
                                By:                     
                                   ----------------------------------





                                     10


<PAGE>   118




                                ASSIGNMENT FORM



To assign this Security, fill in the form below:

I or we assign and transfer this Security to


- --------------------------------------------------------------------------------
             (Print or type assignee's name, address and zip code)


- --------------------------------------------------------------------------------
              (Insert assignee's social security or tax I.D. No.)


and irrevocably appoint _________ agent to transfer this Security on the books 
of the Company.  The agent may substitute another to act for him.



Dated:                  Your Signature:
       ----------------                -----------------------------------------


- --------------------------------------------------------------------------------
Sign exactly as your name appears on the other side of this Security.


Signature Guarantee:


- -------------------------------
Signature must be guaranteed


- --------------------------------------------------------------------------------
Notice: Signature(s) must be guaranteed by an institution which is a participant
        in the Securities Transfer Agent Medallion Program ("STAMP") or similar
        program.



                                      11


<PAGE>   119




                       OPTION OF HOLDER TO ELECT PURCHASE

     If you want to elect to have this Security purchased by the Company
pursuant to Section 4.07 or Section 4.09 of the Indenture, check the
appropriate box:

                               Section 4.07  [  ]

                               Section 4.09  [  ]

     If you want to elect to have only part of this Security purchased by the
Company pursuant to Section 4.07 or Section 4.09 of the Indenture, state the
amount in principal amount (must be an integral of $1,000):  $_______________



Dated:                 Your Signature:
       ---------------                ------------------------------------------
                                          (Sign exactly as your name appears on
                                             the other side of this Security.)

Signature Guarantee:
                      ------------------------------
                      (Signature must be guaranteed)



- --------------------------------------------------------------------------------
Notice: Signature(s) must be guaranteed by an institution which is a participant
        in the Securities Transfer Agent Medallion Program ("STAMP") or similar
        program.







                                      12


<PAGE>   120




                                                                       EXHIBIT C
                         FORM OF SUPPLEMENTAL INDENTURE


     SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of
_______________, among [GUARANTOR] (the "New Guarantor"), a subsidiary of DI
Industries, Inc. (or its successor), a Texas corporation (the "Company"), DI
INDUSTRIES, INC., the Guarantors (the "Existing Guarantors") under the
Indenture referred to below, and Texas Commerce Bank National Association, a
national banking association, as trustee under the Indenture referred to below
(the "Trustee").

                             W I T N E S S E T H :

     WHEREAS the Company has heretofore executed and delivered to the Trustee
an Indenture (as such may be amended from time to time, the "Indenture"), dated
as of June 27, 1997, providing for the issuance of an aggregate principal
amount of $175,000,000 of 8-7/8% Senior Notes due 2007 (the "Securities");

     WHEREAS Section 11.08 of the Indenture provides that the Company is
required to cause the New Guarantor to execute and deliver to the Trustee a
supplemental indenture pursuant to which the New Guarantor shall jointly and
severally and unconditionally and irrevocably guarantee all of the Company's
Obligations under the Securities and the Indenture pursuant to a Guarantee
contained in the Indenture on the terms and conditions set forth herein; and

     WHEREAS pursuant to Section 10.01 of the Indenture, the Trustee, the
Company and Existing Guarantors are authorized to execute and deliver this
Supplemental Indenture;

     NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the New
Guarantor, the Company, the Existing Guarantors and the Trustee mutually
covenant and agree for the equal and ratable benefit of the holders of the
Securities as follows:

     1. Definitions.  (a) Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

     (b) For all purposes of this Supplemental Indenture, except as otherwise
herein expressly provided or unless the context otherwise requires:  (i) the
terms and expressions used herein shall have the same meanings as corresponding
terms and expressions used in the Indenture; and (ii) the words "herein,"
"hereof" and "hereby" and other words of similar import used in this
Supplemental Indenture refer to this Supplemental Indenture as a whole and not
to any particular section hereof.

     2. Agreement to Guarantee.  The New Guarantor hereby agrees, jointly and
severally and unconditionally and irrevocably, with all other Guarantors, to
guarantee the 


                                      1


<PAGE>   121




Company's Obligations under the Securities and the Indenture on the terms and
subject to the conditions set forth in Article 11 of the Indenture and to be
bound by all other applicable provisions of the Indenture. From and after the
date hereof, the New Guarantor shall be a Guarantor for all purposes under the
Indenture and the Securities.

     3. Ratification of Indenture; Supplemental Indentures Part of Indenture.
Except as expressly amended hereby, the Indenture is in all respects ratified
and confirmed and all the terms, conditions and provisions thereof shall remain
in full force and effect.  This Supplemental Indenture shall form a part of the
Indenture for all purposes, and every Holder of Securities heretofore or
hereafter authenticated and delivered shall be bound hereby.

     4. Governing Law.  THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

     5. Trustee Makes No Representation. The Trustee makes no representation as
to the validity or sufficiency of this Supplemental Indenture.

     6. Counterparts.  The parties may sign any number of copies of this
Supplemental Indenture.  Each signed copy shall be an original, but all of them
together represent the same agreement.

     7. Effect of Headings.  The Section headings herein are for convenience
only and shall not effect the construction thereof.

     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                             [NEW GUARANTOR]              
                                                          
                                                          
                             By:  
                                -------------------------------------------
                             Name:                        
                             Title:                       
                                                          
                                                          
                                                          
                                                          
                                                          
                             DI INDUSTRIES, INC.          
                                                          
                                                          
                             By:                          
                                -------------------------------------------
                             Name:                        
                             Title:                       
                                                          
                             [ALL EXISTING GUARANTORS]    
                                                          
                                                          
                             By:                          
                                -------------------------------------------
                             Name:                        
                             Title:                       



                             TEXAS COMMERCE BANK NATIONAL ASSOCIATION
                             as Trustee                              
                                                                     
                                                                     
                             By:                                     
                                -------------------------------------------
                             Name:                                   
                             Title:                                  
                                                                     
                                                                     





                                      2

<PAGE>   122



                             SUPPLEMENTAL INDENTURE


         SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE"), dated as of
March 31, 1998, among (i) MURCO DRILLING CORPORATION, a Delaware corporation
(the "NEW GUARANTOR"), a subsidiary of GREY WOLF, INC. (formerly "DI Industries,
Inc."), a Texas corporation (the "COMPANY"), (ii) the Company, (iii) the
Guarantors (the "EXISTING GUARANTORS") under the Indenture referred to below,
and (iv) CHASE BANK OF TEXAS NATIONAL ASSOCIATION (formerly "Texas Commerce Bank
National Association"), a national banking association, as trustee under the
Indenture referred to below (the "TRUSTEE").

                              W I T N E S S E T H:

         WHEREAS the Company has heretofore executed and deliver to the Trustee
an Indenture (as such may be amended from time to time, the "INDENTURE"), dated
as of June 27, 1997, providing for the issuance of an aggregate principal amount
of $175,000,000 of 8-7/8% Senior Notes due 2007 (the "SECURITIES");

         WHEREAS Section 11.08 of the Indenture provides that the Company is
required to cause the New Guarantor to execute and deliver to the Trustee a
supplemental indenture pursuant to which the New Guarantor shall jointly and
severally and unconditionally and irrevocably guarantee all of the Company's
Obligations under the Securities and the Indenture pursuant to a Guarantee
contained in the Indenture on the terms and conditions set forth herein; and

         WHEREAS pursuant to Section 10.01 of the Indenture, the Trustee, the
Company and Existing Guarantors are authorized to execute and deliver this
Supplemental Indenture;

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the New
Guarantor, the Company, the Existing Guarantors and the Trustee mutually
covenant and agree for the equal and ratable benefit of the holders of the
Securities as follows:

         1.       Definitions.  (a)  Capitalized terms used herein without 
definition shall have the meanings assigned to them in the Indenture.

                  (b) For all purposes of this Supplemental Indenture, except as
otherwise herein expressly provided or unless the context otherwise requires:
(i) the terms and expression used herein shall have the same meanings as
corresponding terms and expressions used in the Indenture; and (ii) the words
"herein," "hereof" and "hereby" and other words of similar import used in this
Supplemental Indenture refer to this Supplemental Indenture as a whole and not
to any particular section hereof.





<PAGE>   123



         2. Agreement to Guarantee. The New Guarantor hereby agrees, jointly and
severally and unconditionally and irrevocable, with all other Guarantors, to
guarantee the Company's Obligations under the Securities and the Indenture on
the terms and subject to the conditions set forth in Article 11 of the Indenture
and to be bound by all other applicable provisions of the Indenture. From and
after the date hereof, the New Guarantor shall be a Guarantor for all purposes
under the Indenture and the Securities.

         3. Ratification of Indenture; Supplemental Indentures Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed and all of the terms, conditions and provisions thereof
shall remain in full force and effect. This Supplemental Indenture shall form a
part of the Indenture for all purposes, and every Holder of Securities
heretofore or hereafter authenticated shall be bound hereby.

         4. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

         5. Trustee Makes No Representation. The Trustee makes no representation
as to the validity or sufficiency of this Supplemental Indenture.

         6. Counterparts. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

         7. Effect of Headings. The Section headings herein are for convenience
only and shall not effect the construction thereof.

         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                       MURCO DRILLING CORPORATION


                       By:  /s/ DAVID W. WEHLMANN
                          ------------------------------------------------------
                       Name:  David W. Wehlmann
                       Title: Secretary

                       GREY WOLF, INC.


                       By:  /s/ DAVID W. WEHLMANN
                          ------------------------------------------------------
                       Name:  David W. Wehlmann
                       Title:  Senior Vice President and Chief Financial Officer


                                        2

<PAGE>   124



                      GREY WOLF DRILLING COMPANY
                      DI INTERNATIONAL, INC.
                      DI ENERGY, INC.


                      By:  /s/ DAVID W. WEHLMANN
                         -------------------------------------------------------
                      Name:    David W. Wehlmann
                      Title:Senior Vice President and Chief Financial Officer of
                      each of the above Guarantors


                      CHASE BANK OF TEXAS NATIONAL ASSOCIATION,
                      as Trustee

                      By:  /s/ MAURI J. COWEN
                         -------------------------------------------------------
                      Name:    Mauri J. Cowen
                      Title:   Vice President and Trust Officer



                                        3
<PAGE>   125

================================================================================



                                GREY WOLF, INC.,

                         THE GUARANTORS PARTIES HERETO

                                      and

                   CHASE BANK OF TEXAS, NATIONAL ASSOCIATION
                                   as Trustee

                          -------------------------

                         SECOND SUPPLEMENTAL INDENTURE

                            Dated as of May 8, 1998

                                       to

                                   INDENTURE

                           Dated as of June 27, 1997

                          -------------------------

                          8-7/8% Senior Notes due 2007



================================================================================

                                                                                
<PAGE>   126



                         SECOND SUPPLEMENTAL INDENTURE

         THIS SECOND SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"),
dated as of May 8, 1998, is by and among Grey Wolf, Inc., a Texas corporation
formerly known as DI Industries, Inc. (the "Company"), the guarantors parties
hereto (the "Guarantors"), and Chase Bank of Texas, National Association,
formerly known as Texas Commerce Bank National Association, as trustee (the
"Trustee").  All terms not defined herein shall have the meanings assigned to
them in the Indenture defined below, as such Indenture is amended by this
Supplemental Indenture.

                                    RECITALS

         A.      The Company, the Guarantors (other than Murco Drilling
Corporation) and the Trustee entered into an indenture, dated as of June 27,
1997 (the "Indenture"), relating to $175,000,000 of the Company's 8-7/8% Senior
Notes due 2007 (the "Securities").

         B.      Murco Drilling Corporation became a Guarantor under the
Indenture pursuant to the Supplemental Indenture dated as of March 31, 1998.

         C.      The Company, the Guarantors and the Trustee desire to enter
into a new indenture (the "Series B Indenture"), relating to $75,000,000 of
8-7/8% Senior Notes due 2007 to be issued by the Company (the "Series B
Notes").

         D.      Pursuant to Section 10.02 of the Indenture, the Company
desires to amend the Indenture to permit the execution and delivery of the
Series B Indenture by the Guarantors and the issuance of guarantees of the
Series B Notes.

         E.      Pursuant to Section 10.01(a)(vii) of the Indenture, the
Company desires to amend the Indenture to cure an ambiguity therein caused by
clerical error.

         F.      All conditions precedent provided for in the Indenture
relating to this Supplemental Indenture have been complied with.

         NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH, the Company,
the Guarantors and the Trustee mutually covenant and agree for the equal and
proportionate benefit of all Holders of the Securities as follows:

                                  ARTICLE ONE

                             Amendment of Indenture

                 Section 1.1  Amendment to Definition of "Consolidated Interest
Expense" in Section 1.01 of the Indenture.  The last sentence of the definition
of the term "Consolidated Interest Expense" in Section 1.01 of the Indenture is
hereby amended by deleting the words "the numerator of which is the amount of
such dividend requirements," and substituting in lieu thereof the words "the
numerator of which is one,".





                                      -1-
<PAGE>   127





         Section 1.2  Amendment to Definition of "Permitted Indebtedness" in 
Section 1.01 of the Indenture.  Clause (f) of the definition of the term
"Permitted Indebtedness" in Section 1.01 of the Indenture is hereby amended by
deleting the existing clause (f) and substituting in lieu thereof the
following:

                 "(f) (1) the Guarantees of the Securities (and any assumption
         of the Obligations guaranteed thereby) and (2) Indebtedness of a
         Guarantor constituting a guarantee of Indebtedness of the Company
         incurred in compliance with Section 4.03 of this Indenture (and any
         assumption of the Obligations guaranteed thereby);".

                                  ARTICLE TWO

                            Miscellaneous Provisions

         Section 2.1  Counterparts.  This Supplemental Indenture may be signed
in counterparts and by the different parties hereto in separate counterparts,
each of which shall constitute an original and all of which together shall
constitute one and the same instrument.

         Section 2.2  Severability.  In case any provision in this Supplemental
Indenture shall be invalid, illegal or unenforceable, the validity, legality
and enforceability of the remaining provisions shall not in any way be affected
or impaired thereby.

         Section 2.3  Headings.  The headings of the Articles and Sections of
this Supplemental Indenture have been inserted for convenience of reference
only, are not to be considered a part hereof and shall not modify or restrict
any of the terms or provisions hereof.

         Section 2.4  Successors.  All agreements of the Company and the
Guarantors in this Supplemental Indenture shall bind their respective
successors.  All agreements of the Trustee in this Supplemental Indenture shall
bind its successors.

         Section 2.5  Governing Law.  THIS SUPPLEMENTAL INDENTURE SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK
BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE
EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE
REQUIRED THEREBY.

         Section 2.6  Effect of Supplemental Indenture.  Except as amended by
this Supplemental Indenture, the terms and provisions of the Indenture shall
remain in full force and effect.





                                      -2-
<PAGE>   128



         Section 2.7  Trustee. The Trustee accepts the modifications of trusts
referenced in the Indenture and effected by this Supplemental Indenture.
Without limiting the generality of the foregoing, the Trustee assumes no
responsibility for the correctness of the recitals herein contained, which
shall be taken as the statements of the Company and the Guarantors, and the
Trustee shall not be responsible or accountable in any way whatsoever for or
with respect to the validity or execution or sufficiency of this Supplemental
Indenture, and the Trustee makes no representation with respect thereto.

         IN WITNESS WHEREOF, the parties hereto have executed this Supplemental
Indenture as of the date first above written.

                                             GREY WOLF, INC.


                                             By: /s/ DAVID W. WEHLMANN
                                                 -------------------------------
                                             Name:  David W. Wehlmann
                                             Title: Senior Vice President and 
                                                    Chief Financial Officer



                                             CHASE BANK OF TEXAS,
                                               NATIONAL ASSOCIATION, as Trustee


                                             By: /s/ MAURI J. COWEN
                                                 -------------------------------
                                             Name:  Mauri J. Cowen
                                             Title: Vice President and Trust 
                                                    Officer


                                             GUARANTORS:

                                             GREY WOLF DRILLING COMPANY
                                             GREY WOLF INTERNATIONAL, INC.
                                             DI ENERGY, INC.
                                             MURCO DRILLING CORPORATION


                                             By: /s/ DAVID W. WEHLMANN
                                                 -------------------------------
                                             Name:  David W. Wehlmann
                                             Title: Secretary
                                                    Of each of the above 
                                                    Guarantors





                                      -3-


© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission