<PAGE>
EXHIBIT 10.12
AMENDMENT #1 TO
THE
OEM PURCHASE AND SALE
AGREEMENT
BY AND BETWEEN
NORTEL NETWORKS
AND
CHORUM TECHNOLOGIES
This amendment (the "Amendment") is made this 12th day of October, 2000 (the
"Effective Date") by and between Nortel Networks, Ltd., having an office at 8200
Dixie Road, Brampton, Ontario L6T 5P6 ("Nortel") and Chorum Technologies, Inc.
("Seller") having an office at 1303 E. Arapaho Road, Richardson, Texas 75081.
Whereas, Nortel and Seller entered into an OEM Purchase and Sale Agreement,
effective as of 1 January 2000 (the "OEM Agreement"), and,
Whereas, the parties desire that this Amendment revise the OEM Agreement.
Now therefore, for good and valuable consideration, the receipt and sufficiency
of which the parties acknowledge, the parties hereby amend the OEM Agreement as
follows:
1. Insert the following as Section 8.5.6:
[*]
All capitalized terms herein will have the meaning set forth in the OEM
Agreement. Except as specifically provided above, the OEM Agreement shall
remain in full force and effect without modification.
THE REST OF THIS PAGE IS INTENTIONALLY LEFT BLANK; THE NEXT PAGE IS THE
SIGNATURE PAGE.
* Certain information on this page has been omitted and filed separately with
the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.
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IN WITNESS WHEREOF, the Parties hereto have executed this Amendment #1 on the
day and year last written below.
CHORUM TECHNOLOGIES INCORPORATED NORTEL NETWORKS LIMITED
By: By:
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(Signature) (Signature)
Name: Name:
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Title: Title:
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(Print) (Print)
Date: Date:
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