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                                                                   EXHIBIT 10.28

                                    AGREEMENT

     This Agreement dated as of January 21, 2000 is entered into by and between
Caminus LLC, a Delaware limited liability company (the "Company"), and GFI Two
LLC (formerly, GFI Energy Ventures LLC) ("GFI").

     WHEREAS, the Company and GFI are each party to that certain Limited
Liability Company Agreement dated as of May 12, 1998 (the "LLC Agreement");

     WHEREAS, pursuant to Section 6.5.2 of the LLC Agreement, GFI provides
certain financial, strategic mergers and acquisition, tax and general
administrative services to the Company in exchange for certain payments by the
Company;

     WHEREAS, the Company is effecting a reorganization (the "Reorganization")
pursuant to which the members of the Company will exchange their shares of
membership interest in the Company for shares of common stock of a Delaware
C-corporation (the "Surviving Corporation");

     WHEREAS, effective upon the closing of the Reorganization and pursuant to
that certain Merger Agreement by and among the Company, the Surviving
Corporation and a wholly-owned subsidiary of the Surviving Corporation, certain
portions of the LLC Agreement, including Section 6.5.2 thereof, will be
terminated; and

     WHEREAS, the Company and GFI desire to formally memorialize their mutual
understanding with respect to the termination of Section 6.5.2 of the LLC
Agreement and the payment in full by the Company of all amounts due thereunder
to GFI for financial, tax and general administrative services provided by GFI to
the Company.

     NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, the receipt and sufficiency of which are hereby acknowledged,
the Company and GFI agree as follows:

     1.   Effective upon the closing of the Reorganization, (i) the provisions
of Section 6.5.2 of the LLC Agreement be and hereby are terminated and (ii)
except as set forth in Section 2 below, the Company and GFI hereby waive their
respective rights and hereby release each other from their respective
obligations under Section 6.5.2 of the LLC Agreement.

     2.   Notwithstanding the foregoing, (i) the Company shall continue to pay
GFI a management fee, calculated in accordance with Section 6.5.2 of the LLC
Agreement, for financial, tax and general administrative services provided by
GFI through the Reorganization; and (ii) within three business days following
the closing date of the

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initial public offering of common stock of the Surviving Corporation, the
Company shall pay to GFI an amount equal to $1,300,000 in consideration for
termination of the provisions of Section 6.5.2 of the LLC Agreement.

     3.   If the initial public offering does not close by February 15, 2000,
this Agreement will automatically terminate and be of no force or effect
proactively or retroactively and the Company and GFI will both be in such
position as if this Agreement was never entered into.

     4.   The existence, validity and construction of this Agreement shall be
governed by the laws of the State of Delaware.

     5.   This Agreement may be executed in any number of counterparts, and each
such counterpart shall be deemed to be an original instrument, but all such
counterparts together shall constitute but one agreement.

     IN WITNESS WHEREOF the parties hereto have executed this Amendment on the
date first above written.

                                          CAMINUS LLC

                                          /s/ Mark A. Herman
                                          -----------------------------
                                          By:  Mark A. Herman
                                          Its: CFO

                                          GFI TWO LLC
                                          /s/ Lawrence D. Gilson
                                          ------------------------------
                                          By:  Lawrence D. Gilson
                                          Its: Chairman



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