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                                                                     Exhibit 5.1

                            MORRISON & FOERSTER LLP
                             Palo Alto, California


                                 April 21, 1997




Infinity Financial Technology, Inc.
640 Clyde Court
Mountain View, CA 94043

Gentlemen:

    At your request, we have examined the Registration Statement on Form S-8
executed by you on April 21, 1997, and to be filed with the Securities and
Exchange Commission (the "SEC") in connection with the registration under the
Securities Act of 1933, as amended, of an aggregate of 9,050,000 shares of your
common stock, $.001 par value (the "Common Stock") which will be issuable under
the 1989 Stock Option Plan and the 1993 Stock Incentive Plan (the "Plans").

    As your counsel in connection with the Registration Statement, we have
examined the proceedings taken by you in connection with the adoption of the
Plans and the authorization of the issuance of the shares of Common Stock under
the Plans (the "Plan Shares") and such documents as we have deemed necessary to
render this opinion.

    Based upon the foregoing, it is our opinion that the Plan Shares, when
issued and outstanding pursuant to the terms of the Plans, will be validly
issued, fully paid and nonassessable shares of Common Stock.

    We consent to the use of this opinion as an exhibit to the Registration
Statement.



                                      Very truly yours,
                                      /s/ Morrison & Foerster LLP