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                                                                   Exhibit 10.15


                      AMENDMENT TO STOCK PURCHASE AGREEMENT


         This Amendment to Stock Purchase Agreement is made and entered into on
December 22, 1999 between Peachtree FiberOptics, Inc. d/b/a vFinance.com, a
Delaware corporation (the "Seller"), and River Rapids LTD (the "Buyer").

                                     RECITAL

         The Seller desires to amend and the Buyer desires to amend that Stock
Purchase Agreement dated September 27, 1999 by and between the Seller and the
Buyer (the "Stock Purchase Agreement"), upon the terms and subject to the
conditions contained herein.

         NOW, THEREFORE, the parties agree as follows:

1. AMENDMENT OF SECTION 1.2. Section 1.2 of the Stock Purchase Agreement shall
be deleted in its entirety and replaced with the following provision:

                  1.2 THE OPTION. The Buyer has the right to exercise the Option
                  to purchase all but not less than all of the Option Shares,
                  commencing on the "Funding", as defined herein below, and
                  terminating at 5:00 P.M. (Miami, Florida time) on September
                  27, 2002 (the "Exercise Period"). The exercise price of the
                  Option is (the "Option Exercise Price") is a follows:

                  210,000 common shares of Seller at $3.00 per share;
                  210,000 common shares of Seller at $4.00 per share; and
                  210,000 common shares of Seller at $5.00 per share

                  For purposes of this Agreement "Funding" shall be defined as
                  the date upon which Seller: (i) has sold substantially all its
                  business or otherwise merged with or been acquired by a third
                  party; or (ii) has received on a cumulative basis net proceeds
                  (net of cash commissions) from the sale of its capital stock
                  (excluding the Shares purchased pursuant to Section 1.1) equal
                  to or greater than $5,000,000 including any capital
                  transaction, or series of capital transactions, from any
                  source whatsoever. For purposes of this Agreement, the merger
                  of vFinance Holdings, Inc. (vFinance.com) and/or Union
                  Atlantic LC into Seller shall not be considered a "Funding".
                  In the event there is no Funding by Seller by April 15, 2000,
                  the Exercise Period shall terminate immediately and the Option
                  shall be cancelled and shall deemed null and void and of no
                  further force and effect. In order to exercise the Option, the
                  Option Exercise Price must be paid in full by wire transfer of
                  immediately available funds to a bank designated by the Seller
                  during the Exercise Period. The Seller hereby represents that
                  the Option Shares will be free and clear of all pledges,
                  liens, security interests, encumbrances or other restrictions
                  arising from the Seller (except restrictions on resale under
                  state or federal securities laws). Upon exercise of the Option
                  and payment of the Option Exercise Price, the Seller shall
                  deliver to the Buyer a certificate representing the Option
                  Shares. The Option Shares shall be issued in the name of River
                  Rapids LTD.

2. FULL FORCE AND EFFECT. All other provisions of the Stock Purchase Agreement
shall remain in full force and effect.

IN WITNESS WHEREOF, the parties have executed this Amendment as of the date
first hereinabove written.



PEACHTREE FIBEROPTICS, INC.                      RIVER RAPIDS LTD.




By: /s/ Leonard Sokolow                          By:  /s/
    ------------------------------------             ---------------------------
         Leonard J. Sokolow, President                Authorized Representative





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