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                                                                    EXHIBIT 10.4

                           PLEDGE AGREEMENT SUPPLEMENT

         PLEDGE AGREEMENT SUPPLEMENT dated as of June 4, 2002 between Nortel
Networks Singapore Pte Ltd, (the "LIEN GRANTOR") and JPMORGAN CHASE BANK, as
Collateral Agent.

         WHEREAS, Nortel Networks International Finance and Holding B.V., Nortel
Communications Holdings (1997) Limited, Nortel Networks AB and JPMorgan Chase
Bank, as Collateral Agent, are parties to a Foreign Pledge Agreement dated as of
the first day of the Collateral Period (as heretofore amended and/or
supplemented, the "PLEDGE AGREEMENT");

         WHEREAS, Nortel Networks Singapore Pte Ltd. desires to become a party
to the Pledge Agreement as a Lien Grantor thereunder; and

         WHEREAS, terms defined in the Pledge Agreement and not otherwise
defined herein have, as used herein, the respective meanings provided for
therein;

         NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

           1. Pledge of Equity Interest. (a) The Lien Grantor, in order to
secure its Secured Obligations, grants to the Collateral Agent for the benefit
of the Secured Parties, effective on the first day of any Collateral Period, a
continuing security interest in all Equity Interests in the Subsidiary
identified in Schedule I hereto held directly by the Lien Grantor and all of its
rights and privileges with respect thereto, and all income and profits thereon,
all interest, dividends and other payments and distributions with respect
thereto, whether now owned or existing or hereafter acquired or arising and
regardless of where located (the "ADDITIONAL COLLATERAL"). The security
interests granted by the Lien Grantor pursuant to this Section 1(a) shall
terminate in accordance with Section 17 of the Pledge Agreement.

                  (b) The foregoing Pledge is granted as security only and shall
not subject the Collateral Agent or any other Secured Party to, or transfer or
in any way affect or modify, any obligation or liability of the Lien Grantor
with respect to any of the Additional Collateral or any transaction in
connection therewith.

           2. Party to Pledge Agreement. Upon delivering this Pledge Agreement
Supplement to the Collateral Agent, the Lien Grantor will become a party to the




<PAGE>


Pledge Agreement and will thereafter have all the rights and obligations of a
Lien Grantor thereunder and be bound by all the provisions thereof as fully as
if it were one of the original parties thereto.

          3. Representations and Warranties. Each of the representations and
warranties set forth in the Pledge Agreement are true as applied to the Lien
Grantor and the Additional Collateral on the date specified therein, other than
the representations and warranties set forth in Section 3(e) and (f). For
purposes of the foregoing sentence, references in said Sections to "Lien
Grantor" shall be deemed to refer to the Lien Grantor, references to "Schedules"
to the Pledge Agreement shall be deemed to refer to the corresponding Schedules
to this Pledge Agreement Supplement, references to "Collateral" shall be deemed
to refer to the Additional Collateral.

           4. Governing Law. This Pledge Agreement Supplement shall be construed
in accordance with and governed by the laws of the State of New York.


                                       2

<PAGE>


         IN WITNESS WHEREOF, the parties hereto have caused this Pledge
Agreement Supplement to be duly executed by their respective authorized officers
as of the day and year first above written.

                                  NORTEL NETWORKS SINGAPORE PTE LTD


                                  By: /s/ Robert Ferguson
                                      ---------------------------------
                                      Name: Robert Ferguson
                                      Title: Vice-President


                                       3

<PAGE>


                                  JPMORGAN CHASE BANK,
                                  as Collateral Agent


                                  By:/s/ Edmund De Forest
                                     ----------------------------------
                                     Name: Edmund De Forest
                                     Title: Vice-President


                                       4

<PAGE>


                                   SCHEDULE I
               PLEDGED EQUITY INTERESTS IN MATERIAL SUBSIDIARIES
                            OWNED BY THE LIEN GRANTOR
                             (AS OF THE DATE HEREOF)



<TABLE>
<CAPTION>

                          JURISDICTION                                                 NUMBER OF
                              OF              OWNER OF EQUITY         PERCENTAGE       SHARES OR
ISSUER                    ORGANIZATION           INTERESTS              OWNED            UNITS
------                    ------------        ---------------         ----------       ---------
<S>                       <C>                 <C>                      <C>              <C>
Nortel Networks (India)    India               Nortel Networks          0.01%            1
Private Limited.                               Singapore Pte Ltd

</TABLE>



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