S1 CORP /DE/
AMENDMENT TO STOCK PURCHASE AGREEMENT
<DOCUMENT>
<TYPE>EX-10.12
<SEQUENCE>2
<FILENAME>w47265ex10-12.txt
<DESCRIPTION>AMENDMENT TO STOCK PURCHASE AGREEMENT
<TEXT>

<PAGE>   1

                                                                   Exhibit 10.12

                 AMENDMENT NO. 2 TO STOCK PURCHASE AGREEMENT II

        This Amendment No. 2 (the "Amendment") is made as of November 27, 2000,
to that certain Stock Purchase Agreement II, dated as of September 21, 1999 (the
"Agreement"), by and among S1 Corporation, a Delaware corporation f/k/a Security
First Technologies Corporation ("S1"), and the individuals and entities that are
signatories thereto (each a "Purchaser" and collectively, "Purchasers") and FICS
Group N.V., a Belgian corporation (naamloze vennootschap ("N.V.")) ("FICS") for
the limited purposes set forth therein. Capitalized terms used herein but not
defined shall have the meanings ascribed to such terms in the Agreement.

                                    RECITALS:

        A.      The parties hereto entered into the Agreement pursuant to which
the Purchasers agreed to purchase, and S1 agreed to sell, a certain number of
shares of S1 Common Stock upon the terms and conditions contained in the
Agreement.

        B.      The Holdings Purchase Agreement is being amended concurrently
herewith.

        C.      The parties wish to amend the Agreement to conform with the
amendment to the Holdings Purchase Agreement.

                                   AGREEMENT:

        NOW, THEREFORE, in consideration of the foregoing Recitals and the
mutual promises, representations, warranties, covenants and conditions set forth
herein and in the Agreement, the sufficiency of which is hereby acknowledged,
the parties mutually agree as follows:

        1.      Pursuant to Section 10.6 of the Agreement, the parties agree
that the Agreement shall be amended as follows:

                a.      The term "Holdings Purchase Agreement" as referenced in
                        the Agreement shall refer to the Holdings Purchase
                        Agreement as defined therein, as amended prior to and as
                        of the date hereof.

                b.      Section 1.2(a) of the Agreement is hereby amended and
                        restated in its entirety to read as follows: "(a) Upon
                        the Second Closing, the Purchasers shall Purchase from
                        S1, and S1 agrees to sell to the Purchasers 1,800,000
                        shares of S1 Common Stock (the "2000 Earn-out Shares")."

<PAGE>   2

                c.      Section 1.2(b) of the Agreement is hereby deleted in its
                        entirety and Section 1.2(c) shall be renumbered as
                        Section 1.2(b).

                d.      Section 7.2(b)(1) of the Agreement is hereby amended and
                        restated in its entirety to read as follows: "(b)
                        $12,375,000 in cash."

                e.      Notwithstanding anything to the contrary in the
                        Agreement, the parties hereby agree that (a) the term
                        "2000 Earn-out Consideration" as referenced in the
                        Agreement shall mean $12,375,000 and (b) the term "2001
                        Earn-out Consideration" as referenced in the Agreement
                        shall mean $0. The parties hereby agree that as of the
                        date hereof S1 shall have no further obligation to sell
                        any shares of its capital stock other than its
                        obligation to sell the 2000 Shares at the Second Closing
                        (as the meanings of such terms are amended herein).

                f.      Notwithstanding anything to the contrary in the
                        Agreement, the terms "2001 Shares" and "2001 Earn-out
                        Shares" shall mean zero shares.

                g.      Sections 1.5, 7.1(c) and 7.2(c) of the Agreement are
                        hereby deleted in their entirety.

        2.      The parties hereby agree that, upon consummation of the sale of
the 2000 Earn-out Shares as contemplated hereby, the terms of Section 5.2 of the
Agreement have been fulfilled and that S1 has no further obligations to the
Purchasers or FICS pursuant to such section.

        3.      Except as contemplated herein, the Agreement shall otherwise
continue in full force and effect.

        4.      This Amendment may be executed in two or more counterparts, any
one of which may contain only one signature, and all the counterparts taken
together shall constitute a single agreement. This Amendment may also be
executed and delivered by facsimile transmission.




                      [THIS SPACE INTENTIONALLY LEFT BLANK]



                                     - 2 -
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        IN WITNESS WHEREOF, the undersigned have each executed this Amendment as
of the date first set forth above.

                                      S1 CORPORATION



                                      By:   /s/ Robert F. Stockwell
                                            ------------------------------------
                                            Name:
                                            Title:

<PAGE>   4

THE PURCHASERS:


/s/ Michel Akkermans
-----------------------------------------
MICHEL AKKERMANS


PAMICA N.V.



By: /s/ Michel Akkermans
    -------------------------------------
    Name:  Michel Akkermans
    Title: Managing Director



GENERAL ATLANTIC PARTNERS 20, L.P.
By: GENERAL ATLANTIC PARTNERS, LLC, its General Partner


    By: /s/ Matthew Nimetz
        ---------------------------------
        Name:  Matthew Nimetz
        Title: A Managing Member



GENERAL ATLANTIC PARTNERS 52, L.P.
By: GENERAL ATLANTIC PARTNERS, LLC, its General Partner


    By: /s/ Matthew Nimetz
        ------------------
        Name:  Matthew Nimetz
        Title: A Managing Member



GAP COINVESTMENT PARTNERS, L.P.



By: /s/ Matthew Nimtez
    -------------------------------------
    Name:  Matthew Nimetz
    Title: A General Partner


<PAGE>   5


GIMV N.V.



By:   /s/ G. Mampery               /s/ P. Vercruysse
      ----------------------------------------------
      Name:  G. Mampery            P. Vercruysse
      Title: Vice-President        Vice-President




/s/ Guy Moons
---------------------------------
GUY MOONS



/s/ Steven Van Rossen
---------------------------------
STEVEN VAN ROSSEN



/s/ Nadine Quaeyhaegens
---------------------------------
NADINE QUAEYHAEGENS



/s/ Etienne Castiaux
---------------------------------
ETIENNE CASTIAUX



/s/ Goort Gelten
---------------------------------
GOORT GELTEN



/s/ Loek Van Den Boog
---------------------------------
LOEK VAN DEN BOOG



/s/ Fredrick Dumas
---------------------------------
FREDRICK DUMAS



<PAGE>   6


UNICO PORTFOLIO LTD.



By:   /s/ Luis G. Manzanares          /s/ Shana Louise White
      ------------------------------------------------------
Name:  Luis G. MANZANARES     and         Shana Louise WHITE
Title: President                          Secretary

<PAGE>   7

FICS GROUP N.V.

                            PURSUANT TO SPECIAL PROXY

By: Robert F. Stockwell
    -------------------------------------
    Name:
    Title:
</TEXT>
</DOCUMENT>
