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                                                               EXECUTION VERSION

                                  EXHIBIT 10.1

                                 THIRD AMENDMENT

                  THIRD AMENDMENT (this "Amendment"), dated as of December 22,
2003 to (i) the Letter of Credit Issuance and Reimbursement Agreement, dated as
of May 28, 2003 (as amended, supplemented or otherwise modified from time to
time, the "L/C Agreement"), among Lucent Technologies Inc. (the "Borrower"), the
banks from time to time parties thereto (the "L/C Banks") and JPMorgan Chase
Bank, as Administrative Agent and (ii) the External Sharing Debt Agreement,
dated as of May 28, 2003 (as amended, supplemented or otherwise modified from
time to time, the "ESD Agreement"; together with the L/C Agreement, the "Credit
Agreements"), among the Borrower, the banks from time to time parties thereto
(the "ESD Banks") and JPMorgan Chase Bank, as Administrative Agent.

     1. Defined Terms. Capitalized terms used but not otherwise defined herein
shall have the meanings assigned to such terms in the Credit Agreements.

     2. Amendment to the Credit Agreements. Section 1.01 of each Credit
Agreement is hereby amended by deleting clause (f) of the defined term
"Permitted Investments" and inserting in lieu thereof the following new clause
(f):

                  (f) investments made in compliance with the "Lucent
                  Technologies Global Investment Guidelines", dated November 21,
                  2003.

     3. Conditions to Effectiveness of this Amendment. This Amendment shall
become effective upon the date when the Administrative Agent shall have received
this Amendment, duly executed and delivered by each of (i) the Borrower and (ii)
the Required Lucent Banks.

     4. Continuing Effect of the Credit Documents. The execution, delivery and
effectiveness of this Amendment shall not operate as a waiver of any right,
power or remedy of any Bank or the Administrative Agent under any of the Credit
Documents. Except as expressly amended herein, all of the provisions of the
Credit Agreements and the other Credit Documents are and shall remain in full
force and effect in accordance with the terms thereof and are hereby in all
respects ratified and confirmed.

     5. Representations and Warranties. To induce the Administrative Agent and
the Banks parties hereto to enter into this Amendment, the Borrower hereby
represents and warrants to the Administrative Agent and the Banks that, after
giving effect to this Amendment, (a) the representations and warranties set
forth in Article III in each of the Credit Agreements are true and correct in
all material respects on and as of the date hereof, except to the extent such
representations and warranties expressly relate to a specific earlier date, in
which case such representations and warranties were true and correct in all
material respects as of such earlier date, and (b) no Default or Event of
Default shall have occurred and be continuing as of the date hereof.





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     6. Counterparts. This Amendment may be executed by one or more of the
parties hereto on any number of separate counterparts (including by facsimile),
and all of said counterparts taken together shall be deemed to constitute one
and the same instrument.

     7. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

     8. Expenses. The Borrower agrees to pay or reimburse the Administrative
Agent for all of its out-of-pocket costs and expenses incurred in connection
with the preparation, negotiation and execution of this Amendment, include the
fees and disbursements of counsel to the Administrative Agent.






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                  IN WITNESS WHEREOF, each of the undersigned has caused this
Amendment to be duly executed and delivered as of the date first above written.

                                LUCENT TECHNOLOGIES INC., as the Borrower
                                and as a Grantor



                                By:
                                    ------------------------------------------
                                    Name:
                                    Title: