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                                                                    Exhibit 4.51

    FIFTH AMENDMENT TO CONTRACT ON PROCUREMENT OF TELKOM-2 SATELLITE NO.K.TEL
                  109/HK.920/UTA-00/2005, DATED 30 AUGUST 2005

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Parties:                1.  TELKOM; and

                        2.  Orbital Sciences Corporation ("CONTRACTOR").

Preceding Agreements:   1.  Main agreement - No.K.TEL.191/HK.810/UTA-00/2002
                            dated 24 October 2002;

                        2.  Amendment No. 1 - No.K.TEL.260/HK.820/UTA-00/2003
                            dated 15 December 2003;

                        3.  Amendment No. 2 - No.K.TEL.66/HK.920/UTA-00/2004
                            dated 31 March 2004;

                        4.  Amendment No. 3 - No.Tel.248/HK.930/UTA-00/2004
                            dated 29 October 2004;

                        5.  Amendment No. 4 - No. K.Tel.27/HK.920/UTA-00/2005
                            dated 21 February 2005.

Amended Provisions:     1.  Appendix M, Payment Milestone Schedule, of
                            Amendment No.4;

                        2.  Article 1.27 of Terms and Conditions of the
                            Contract to become as follows: "TRAFFIC TRANSFER
                            shall mean transferring of the entire traffic of
                            Palapa B4 to the TELKOM-2 Satellite as well as
                            TELKOM traffic from TELKOM-1 and CHINASTAR as set
                            fort in the Statement of Work, Appendices A, B and
                            D. Traffic Transfer shall commence within THREE
                            (3) days of Final Acceptance or Qualified
                            Acceptance of the TELKOM-2 Satellite and arrival
                            at the final orbit location and shall be completed
                            no later than TEN (10) calendar days thereafter";

                        3.  To amend Article 1.e of Appendix A, Statement of
                            Work, of the contract to become: "Support the
                            transfer of traffic from PALAPA-B4 as well as
                            TELKOM Traffic on TELKOM-1 and CHINASTAR to
                            TELKOM-2";

                        4.  Article 3.4 of Appendix A, Statement of Work to
                            become: "These activities shall be based on Test
                            Plan and Product Assurance Plan requirements
                            specified in Contract Appendices E and F. The
                            CONTRACTOR shall be fully responsible for all
                            satellite operations since separation from the
                            last stage of the launch vehicle to the beginning
                            of on-station operations, including in-orbit
                            acceptance testing, and collocation operation
                            during Traffic Transfer from PALAPA-B4 and TELKOM
                            traffic.
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                            from TELKOM-1 and CHINASTAR to the TELKOM-2
                            satellite;

                            The CONTRACTOR and the PURCHASER shall utilize the
                            Augmented master Control Station to support
                            eastern hemisphere portion of the transfer orbit
                            operation and in-orbit acceptance testing of
                            TELKOM-2 Satellite. The CONTRACTOR shall manage
                            the handover of stationkeeping operations to the
                            PURCHASER after completion of Traffic Transfer;

                            The CONTRACTOR shall accommodate active
                            participation of the PURCHASER's personnel during
                            launch and transfer orbit activities. Since the
                            TELKOM-2 Satellite will be located in the same
                            orbital position where the PALAPA-B4 Satellite is
                            still in operation, the CONTRACTOR shall carry out
                            TELKOM-2 in-orbit acceptance tests at a position
                            designated by the PURCHASER and support the
                            conduct of Traffic Transfer from PALAPA-B4,
                            TELKOM-1 and Chinastar to TELKOM-2, as set forth
                            in Article 1.27 of the Contract Terms and
                            Conditions. The CONTRACTOR with participation of
                            the PURCHASER shall carry out these activities";

                        5.  Article 2.1.3 of Appendix B, System Specification,
                            of the Amendment No. 2 to become: "The satellite
                            shall have a guaranteed operational service
                            lifetime of 15 years. The considered period of
                            operation shall start at the date the satellite is
                            located at its designated orbital location and
                            traffic transfer has been completed as set forth
                            in Article 1.27 of the Contract Terms and
                            Conditions. Design of all units must allow a
                            sufficient probability of survival of the
                            satellite after 15 years of in-orbit operation.
                            Enough redundancy must be provided and sufficient
                            margins against degradations should be taken;

                            The definition of satellite survival and the
                            required probability of survival are given in
                            section 2.2. The initial propellant loading shall
                            be sufficient for the orbit maneuver life as
                            specified in the TELKOM-2 Bus Performance
                            Specification";

                        6.  Article 1.2.3 of Appendix D, Bus Performance
                            Specification, of the Amendment No.2, to become:
                            "The orbital service life is defined as the span
                            of time, starting at the moment of completion of
                            Traffic Transfer as set forth in article 1.27 of
                            the Contract Terms and Conditions, over which the
                            bus can perform all attitude and orbit control
                            maneuvers, so as to meet the specified antenna
                            pointing accuracy".
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