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                                                                     EXHIBIT 4.5

                       PURCHASER REPRESENTATIVE AGREEMENT

      ACKNOWLEDGMENT AND AGREEMENT, dated for reference purposes as of December
7th, 1999, between Volpe Brown Whelan & Company, LLC (the "Representative") and
the investor named on the signature page to this Agreement (the "Investor").

                                    RECITALS

      A. In connection with the proposed merger of Home Financial Network, Inc.
("Company") and Sybase, Inc. (the "Acquiror"), the Acquiror is offering (the
"Offering") shares of its Common Stock ("Common Stock") to each of the
shareholders, warrant holders, and optionees of Company, including the Investor,
pursuant to an Information Statement dated December 7, 1999.

      B. In order to facilitate the Offering, Representative has agreed to act
as "purchaser representative" (as such term is defined in Rule 501(h) of the
Rules and Regulations promulgated under the Securities Act of 1933, as amended)
for the Investor in connection with the Offering.

                                    AGREEMENT

      NOW, THEREFOR, in consideration of the promises set forth below and for
other good and valuable consideration, the parties thereto hereby acknowledge
and agree as follows:

      1. The Investor acknowledges and confirms that Representative has been
retained by Company on the Investor's behalf to act as the Investor's purchaser
representative in connection with evaluating the merits and risks of the
Offering.

      2. Representative and its affiliates hereby confirm that they have such
knowledge and experience in financial and business matters that they are capable
of evaluating the merits and risks of an investment in the Common Stock of the
Acquiror by the Investor.

      3. Representative represents that neither it nor any of its affiliates
has, is expected to have, or, at any time during the previous two years has had,
any material relationship with the Acquiror or any of its affiliates and that
neither it nor any of its affiliates or employees is (i) an affiliate, director,
officer, or other employee of the Acquiror, or (ii) the beneficial owner of ten
percent (10%) or more of any class of the equity securities of the Acquiror or
ten percent (10%) or more of the equity interest of the Acquiror.

      4. This Agreement embodies the entire agreement of the parties hereto with
respect to the subject matter hereof, and supersedes any and all other
agreements or arrangements, whether written or oral, which the parties hereto
may have had with respect to the subject matter hereof. This Agreement may not
be changed or terminated orally but only by an agreement in writing signed by
each of the parties hereto.

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      5. This Agreement may be executed in any number of counterparts, which
together shall constitute one and the same instrument.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first above written.

                                        REPRESENTATIVE

                                        VOLPE BROWN WHELAN & COMPANY, LLC

                                        By:
                                               ---------------------------------
                                        Name:
                                               ---------------------------------
                                        Title:
                                               ---------------------------------


                                        INVESTOR

                                        INDIVIDUAL

                                        ----------------------------------------
                                        (Signature)

                                        ----------------------------------------
                                        (Type or print Name as it appears on
                                        your Stock Certificate(s))


                                        CORPORATION, PARTNERSHIP OR TRUST

                                        ----------------------------------------
                                                   (Name of Entity)


                                        By:
                                               ---------------------------------
                                        Name:
                                               ---------------------------------
                                        Title:
                                               ---------------------------------

             [Signature page to Purchaser Representative Agreement]