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                                                                Exhibit 10.3

                              FIRST AMENDMENT TO
                       AGREEMENT OF LIMITED PARTNERSHIP
                                      OF
                        HPMC DEVELOPMENT PARTNERS, L.P.


     This First Amendment (the "Amendment") is entered into as of October 8, 
1998 and amends that certain Agreement of Limited Partnership of HPMC 
Development Partners, L.P. (the "Partnership"), dated as of April 23, 1998, 
as previously amended by that certain Supplement thereto (the "Supplement") 
dated as of April 23, 1998 (as amended by such Supplement, the "Partnership 
Agreement"). Capitalized terms that are used in this Amendment but that are 
not otherwise defined herein shall have the meanings set forth in the 
Partnership Agreement.

     Now, therefore, for good and valuable consideration, the receipt and 
sufficiency of which hereby are acknowledged by the Partners, the Partners 
hereby agree as follows (with the Partnership Agreement hereby being amended 
to the extent it is inconsistent with the following provisions):

     1.   USE OF RESERVES.  The Partners hereby approve that $4.6 million of 
the $5 million of Mack-Cali Capital Contributions that currently are being 
held as reserves shall be used to balance the Sanwa construction loan for the 
El Segundo Land (in lieu of such amount continuing to be held as reserves by 
the Partnership or the Mack-Cali Partners being required to make Required 
Additional Contributions to fund such balancing requirement).

     2.  CAPITAL EQUALIZATION; MEZZANINE FINANCING.

         (a)  DEFINITION OF "THIRD PARTY MEZZANINE FINANCING." For purposes 
of applying Sections 2.1.2.3 ("Capital Equalization") and 2.1.2.4. 
("Mezzanine Financing") of the Partnership Agreement, the term "conventional 
financing" with respect to a Property (as used in the definition of the term 
"Third-Party Mezzanine Financing") shall be deemed to mean the portion of the 
Partnership's financing with respect to such Property which will cause such 
Property's development costs to be 50% financed with debt.

         (b)  ADDITIONAL TRIGGER DATE FOR CAPITAL EQUALIZATION. 
Notwithstanding the provisions of Sections 2.1.2.3 ("Capital Equalization") 
and 2.1.2.4 ("Mezzanine Financing") of the Partnership Agreement, the Capital 
Equalization Distribution required under Section 2.1.2.3 of the Partnership 
Agreement (and the Required Additional Contributions of the Mack-Cali 
Partners to make such distribution) shall be required upon the earlier to 
occur of (i) the El Segundo Valuation Date (i.e., the $55 million valuation 
for the El Segundo Land occurring as provided in the definition of such term 
contained in the Partnership Agreement) or (ii) the closing of binding loan 
documentation (the "Construction Loan Closings") for the construction  

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financing for both the El Segundo Land and the Summit Ridge Land if the 
aggregate amount permitted to be borrowed by the Partnership and the 
Investment Entities under such financing ("Maximum Permitted Borrowings") 
exceeds $27.2 million (the date on which the Construction Loan Closing has 
occurred for both Properties is referred to as the "Special Financing 
Equalization Date"). The amount of the Capital Equalization Distribution, and 
the amount of the Required Additional Contributions required to be made by 
the Mack-Cali Partners to fund the same on the Special Financing Equalization 
Date, as a result of the Special Financing Equalization Date occurring by 
reason of the circumstances described in preceding clause (ii) shall not 
exceed the lesser of (A) 75% of the aggregate Third Party Mezzanine Financing 
permitted to be borrowed by the Partnership and the Investment Entities under 
the construction financing with respect to which the Construction Loan 
closing has occurred, or (B) the amount necessary to reduce the Invested 
Capital of the Highridge Partners to 20% of the excess of (1) the total 
development costs of $54,411,200 for both Properties, minus (2) the aggregate 
Maximum Permitted Borrowings under the construction financing for both 
Properties.  In addition to a Capital Equalization Distribution being 
required to occur on the Special Financing Equalization Date, a Capital 
Equalization Distribution may also occur under Section 2.1.2.3 of the 
Partnership Agreement (as amended by the Supplement) if the El Segundo 
Valuation Date has occurred.  Notwithstanding anything contained in the 
Partnership Agreement or in this Amendment to the contrary, the maximum 
aggregate Capital Contributions required to be made by the Mack-Cali Partners 
under the Partnership Agreement and this Amendment for all periods (including 
their initial $5 million Capital contribution, the Required Additional 
Contributions to be contributed by the Mack-Cali Partners under this 
Amendment to make the Capital Equalization Distribution upon the occurrence 
of the Special Financing Equalization Date, and all other Required Additional 
contributions required to be made by the Mack-Cali partners under the 
Partnership Agreement) shall not exceed $19,200,000 less one dollar ($1.00) 
for each dollar by which the Maximum Permitted Borrowings exceed $27,200,000 
(up to a maximum $1 million reduction to $18,200,000).

          (c)PREFERRED RETURN/HIGHRIDGE SUBORDINATED RETURN RATES.
Notwithstanding anything in the Partnership Agreement to the contrary, from 
and after the Equalization Date, the annual percentage rate to be used in 
computing (i) the Highridge subordinated Contribution Return, and (ii) the 
Preferred Return on the Required Additional Contributions of the Mack-Cali 
Partners made by the Mack-Cali Partners to make the Capital Equalization 
Distribution under Section 2.1.2.3 of the Partnership Agreement or 
Section2(b) of this Amendment, shall thereafter accrue at an annual rate 
equal to the 30-day LIBOR rate in effect at the close of each calendar 
quarter plus seven-hundred and fifty (750) basis points, cumulative and 
compounded quarterly (the "Adjusted Return Rate") (and adjusted at the close 
of each calendar quarter).  The distributions of the Partnership (A) under 
Section 4.1.1(a) of the Partnership Agreement in repayment of the 
Undistributed Preferred Return of the Mack-Cali Partners that is computed at 
the Adjusted Return Rate and in repayment of the portion thereof that is 
computed at a 10% annual rate, and (B) under Section 4.1.1(c) of the 
Partnership Agreement in repayment of the Invested Capital of the Mack-Cali 
Partners that bears a Preferred Return computed at the Adjusted Return Rate 
and in repayment of the portion thereof that bears a Preferred Return 
computed at a 10% annual rate, shall be deemed



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to have been made pro rate in repayment of such amounts under such Section 
4.1.1(a) or Section 4.1.1(c), as applicable, in proportion to the amount 
thereof that is computed at the Adjusted Return Rate and the amount thereof 
computed at a 10% annual rate.

     3. REMAINDER OF PARTNERSHIP AGREEMENT. Except as expressly amended 
herein, all provisions of the Partnership Agreement shall remain in full 
force and effect.

     4. COUNTERPART EXECUTION. This Amendment may be executed in several 
counterparts, each of which shall be deemed an original, but all of which 
shall constitute one and the same instrument when taken together. In 
addition, this Amendment may contain more than one counterpart of the 
signature page and this Amendment may be executed by affixing the signatures 
of each of the Partners to one or more of such counterpart signature pages. A 
Partner shall be deemed to have executed and delivered this Amendment if and 
when it has manually executed a counterpart signature page to this 
Amendment, transmitted a copy of the same by facsimile to each other Partner 
at such other Partner's facsimile number set forth in the Partnership 
Agreement, and received a printed confirmation of the successful receipt 
thereof by such other Partner. This Amendment shall not be binding on the 
Partners hereto unless each Partner shall have executed and delivered a copy 
of this Amendment to the other Partners. If this Amendment is executed and 
delivered by facsimile, each Partner who transmits its signature page for 
this Amendment by facsimile shall promptly forward a manually executed 
signature page to each other Partner (but a Partner's failure to do so 
promptly shall not affect the validity of its execution and delivery of this 
Amendment by facsimile transmission).

     5. CONTINUATION OF BUSINESS. The Partnership hereby is reconstituted and 
its business continued pursuant to the Partnership Agreement, as amended by 
this Amendment.

            [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]






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         IN WITNESS WHEREOF, this Supplement is executed, and is effective for
all purposes, as of the date first set forth above.

                              GENERAL PARTNER

                              HCG DEVELOPMENT, L.L.C.,
                              a Delaware limited liability company

                              By: Highridge Asset Management,
                                  L.L.C., a Delaware limited liability
                                  company, Manager

                                  By: Highridge Management, Inc.,
                                      a California corporation,
                                      Managing Member


                                      By: _____________________________
                                          Name:
                                          Title:

                      [SIGNATURES CONTINUED ON NEXT PAGE]



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                              LIMITED PARTNERS:

                              SUMMIT PARTNERS I, L.L.C.,
                              a Delaware limited liability company

                              By: Highridge Asset Management,
                                  L.L.C., a Delaware limited liability
                                  company, Manager

                                  By: Highridge Management, Inc.,
                                      a California corporation,
                                      Managing Member


                                      By: _____________________________
                                          Name:
                                          Title:

                              MACK-CALI CALIFORNIA
                              DEVELOPMENT ASSOCIATES L.P.,    
                              a California limited partnership

                              By: Mack-Cali Sub XXI, Inc., a
                                  Delaware corporation, its
                                  general partner


                                  By: _____________________________
                                      Name:
                                      Title:

                              [END OF SIGNATURES]


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