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                                                                    Exhibit 10.4

                    AMENDMENT TO SECOND AMENDED AND RESTATED
                           REVOLVING CREDIT AGREEMENT

         THIS AMENDMENT TO SECOND AMENDED AND RESTATED REVOLVING CREDIT
AGREEMENT (this "Amendment") is made as of May 29, 1998, by and among AMB
PROPERTY, L.P., a Delaware limited partnership (the "Borrower"), the BANKS
listed on the signature pages hereof, and MORGAN GUARANTY TRUST COMPANY OF NEW
YORK, as Agent.

                              W I T N E S S E T H:

         WHEREAS, the Borrower and the Banks have entered into the Second
Amended and Restated Revolving Credit Agreement, dated as of November 26, 1997
(the "Credit Agreement"); and

                  WHEREAS, the parties desire to modify the Credit Agreement
upon the terms and conditions set forth herein.

                  NOW THEREFORE, for good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties do hereby
agree as follows:

                  1. Definitions. All capitalized terms not otherwise defined
herein shall have the meanings ascribed to them in the Credit Agreement.

                  2. Guaranties. The final sentence of Section 3.3(a) of the
Credit Agreement is hereby deleted, and all references in the Credit Agreement
to "Subsidiary Guaranties" and "Subsidiary Guarantors" are hereby deemed

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deleted. In addition, the Banks hereby confirm that the Unconditional Guaranty
Agreement by AMB Property II, L.P. and Long Gate LLC is hereby terminated and of
no further force or effect.

                  3. Restrictions on Recourse Debt. The following is hereby
added to Section 5.16: "Notwithstanding anything contained herein to the
contrary, in no event shall the Borrower at any time permit its Consolidated
Subsidiaries, other than AMB Property Corporation, to incur third party Recourse
Debt."

                  4. Effective Date. This Amendment shall become effective upon
receipt by the Agent of counterparts hereof signed by the Borrower (the date of
such receipt being deemed the "Effective Date").

                  5. Entire Agreement. This Amendment constitutes the entire and
final agreement among the parties hereto with respect to the subject matter
hereof and there are no other agreements, understandings, undertakings,
representations or warranties among the parties hereto with respect to the
subject matter hereof except as set forth herein.

                  6. Governing Law. This Amendment shall be governed by, and
construed in accordance with, the law of the State of New York.



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                  7. Counterparts. This Amendment may be executed in any number
of counterparts, all of which taken together shall constitute one and the same
agreement, and any of the parties hereto may execute this Amendment by signing
any such counterpart.

                  8. Headings, Etc. Section or other headings contained in this
Amendment are for reference purposes only and shall not in any way affect the
meaning or interpretation of this Amendment.

                  9. No Further Modifications. Except as modified herein, all of
the terms and conditions of the Credit Agreement, as modified hereby shall
remain in full force and effect and, as modified hereby, the Borrower confirms
and ratifies all of the terms, covenants and conditions of the Credit Agreement
in all respects.

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


Borrower:                           AMB PROPERTY, L.P.

                                    By:     AMB Property Corporation,
                                            its general partner

                                    By:______________________________
                                    Name:
                                    Title:


FOR PURPOSES OF CONFIRMING AND RATIFYING THE CONTINUED EFFECTIVENESS OF THE
UNCONDITIONAL GUARANTY AGREEMENT, DATED AS OF NOVEMBER 26, 1997, BY AMB PROPERTY
CORPORATION:

Confirmed and Ratified:

AMB PROPERTY CORPORATION


By:________________________________
    Name:
    Title:

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Agent and Bank:                     MORGAN GUARANTY TRUST COMPANY OF
                                      NEW YORK, as a Bank and as Agent

                                    By:_________________________________________
                                        Name:
                                        Title:

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Co-Agent and Bank:         COMMERZBANK AKTIENGESELLSCHAFT,
                               LOS ANGELES BRANCH


                                    By:_________________________________________
                                        Name:
                                        Title:


                                    By:
                                       _________________________________________
                                        Name:
                                        Title:

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Co-Agent and Bank:         FLEET NATIONAL BANK


                           By:____________________________________
                              Name:
                              Title:

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Co-Agent and Bank:         NATIONSBANK, N.A.(f/k/a/ NationsBank
                             of Texas, N.A.)

                           By:____________________________________
                              Name:
                              Title:



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Co-Agent and Bank:         PNC BANK, NATIONAL ASSOCIATION

                           By:____________________________________
                              Name:
                              Title:

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Bank:                      BANK OF AMERICA, NATIONAL TRUST
                             AND SAVINGS ASSOCIATION

                           By:___________________________________
                              Name:
                              Title:

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Bank:                      SOCIETE GENERALE, SOUTHWEST AGENCY


                           By:
                              ___________________________________
                              Name:
                              Title:

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Bank:                      DRESDNER BANK AG, NEW YORK AND
                              GRAND CAYMAN BRANCHES


                           By:___________________________________
                              Name:
                              Title:


                           By:___________________________________
                              Name:
                              Title:

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Bank:                      BANKERS TRUST COMPANY


                           By:___________________________________
                              Name:
                              Title:

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Bank:                      CORESTATES BANK, N.A.


                           By:___________________________________
                              Name:
                              Title:

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Bank:                      THE BANK OF NOVA SCOTIA, ACTING
                             THROUGH ITS SAN FRANCISCO AGENCY


                           By:___________________________________
                              Name:
                              Title:

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Bank:                      THE INDUSTRIAL BANK OF JAPAN,
                             LIMITED, LOS ANGELES AGENCY


                           By:__________________________________
                              Name:
                              Title:





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Bank:                      UNION BANK OF CALIFORNIA, N.A.


                           By:_________________________________
                              Name:
                              Title:

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