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EXHIBIT 99.3
JOINT FILING AGREEMENT
The undersigned hereby agree that the Statement on Schedule
13D filed herewith (and any amendments thereto), relating to the common stock,
$0.01 par value, of Southern Mineral Corporation, is being filed jointly with
the Securities Exchange Commission pursuant to Rule 13d-1(k)(1) under the
Securities Exchange Act of 1934, as amended, on behalf of each such person.
IN WITNESS WHEREOF, the undersigned have executed this
Agreement.
Dated: August 11, 2000
/s/ Paul J. Coughlin
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Paul J. Coughlin
/s/ Christopher M. Mackey
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Christopher M. Mackey
COMAC ADVISERS, INC.
By:/s/ Paul J. Coughlin
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Name: Paul J. Coughlin
Title: Authorized Signatory
COMAC ASSOCIATES, L.P.
By: CoMac Advisers, Inc.
Its: General Partner
By:/s/ Paul J. Coughlin
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Name: Paul J. Coughlin
Title: Authorized Signatory
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COMAC PARTNERS, L.P.
By: CoMac Associates, L.P.
Its: General Partner
By: CoMac Advisers, Inc.
Its: General Partner
By:/s/ Paul J. Coughlin
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Name: Paul J. Coughlin
Title: Authorized Signatory
COMAC ENDOWMENT FUND, L.P.
By: CoMac Advisers, Inc.
Its: General Partner
By:/s/ Paul J. Coughlin
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Name: Paul J. Coughlin
Title: Authorized Signatory