American Card Technology, Inc.
April 15, 1998
Page 1

                                   HAROLD ROTHSTEIN
                                650 BOCA MARINA COURT
                              BOCA RATON, FLORIDA 33487
- -------------------------------------------------------------------------

                                    April 30, 1998

American Card Technology, Inc.
2470 Windy Hill Road, Suite 300
Marietta, Georgia 30067

     Re:   Bank Loans to American Card Technology, Inc.

Ladies and Gentlemen:

     I refer to (i) a Line of Credit to American Card Technology, Inc. (the
"Company") from Fleet National Bank ("Fleet") in the maximum principal amount of
One Hundred Fifty Thousand and 00/100 Dollars ($150,000.00), as evidenced by a
promissory note in said amount dated June 28, 1996 (the "Fleet Loan"), and (ii)
a Business Installment Loan in the amount of One Hundred Thousand and 00/100
Dollars ($100,000.00) to the Company from The Chase Manhattan Bank ("Chase," and
together with Fleet, sometimes collectively referred to herein as the "Banks"),
as evidenced by a promissory note in said amount dated October 28, 1996 (the
"Chase Loan," and together with the Fleet Loan, sometimes collectively referred
to herein as the "Loans"). I hereby represent to the Company that, as of the
date hereof, I have a net worth in excess of One Million and 00/100 Dollars
($1,000,000.00).

     For good and valuable consideration, I hereby agree to do either of the
following, at my option, if demand is made on the Company by Fleet and/or Chase
with respect to the Fleet Loan and/or the Chase Loan prior to the earlier of (i)
the net proceeds disbursed pursuant to the Company's initial public offering
(the "IPO") equal or exceed $5,100,000.00 or (ii) the closing of a subsequent
debt financing negotiated by Lilly Beter Capital Group ("LBCG").

     1.   Secure replacement financing to pay off the demanded Loan from another
lender on the same terms and conditions as the demanded Loan(s) was originally
made, except that such new loan shall not be due and payable until the earlier
of (i) the net proceeds disbursed pursuant to the IPO equal or exceed
$5,100,000.00, or (ii) the closing of a subsequent debt financing negotiated by
LBCG, or (iii) March 3, 2001; or

     2.   Satisfy the demanded Loan in full, either through the collateral
security I have previously pledged to the Bank with respect to the demanded Loan
or through some other means satisfactory to the Banks.



American Card Technology, Inc.
April 15, 1998
Page 2


     In the event that I personally provide satisfaction of a Loan, the Company
hereby agrees and acknowledges that I shall be subrogated to all rights of the
Bank with respect to that Loan, so that I shall be treated in the same manner as
the Bank would have been treated had the Loan not been satisfied, including,
without limitation, repayment of all amounts I paid to the Bank on behalf of the
Company with respect to the Loan, on the earlier of (i) the net proceeds
disbursed pursuant to the IPO equal or exceed $5,100,000.00, or (ii) the closing
of a subsequent debt financing negotiated by LBCG, or (iii) March 3, 2001.

     If the Company is in agreement with the foregoing, please so indicate by
countersigning below.



                                   Sincerely yours,

                                        /s/ Harold Rothstein
                                   ----------------------------------
                                   Harold Rothstein

ACCEPTED AND AGREED TO AS OF 
THE 30TH DAY OF APRIL, 1998:

AMERICAN CARD TECHNOLOGY, INC.

By:          /s/ Lawrence 0. Perl
     -----------------------------------

     Its Chief Executive Officer