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                                                                    EXHIBIT 4.15


             SUPPLEMENTAL AGREEMENT TO BRIDGE LOAN TRANSACTION DATED
        AUGUST 10, 1999 (AS EXTENDED AND AMENDED TO DATE) BY AND BETWEEN
          LEXON TECHNOLOGIES, INC. ("DEBTOR"), CHICAGO MAP CORPORATION
             AND STEVEN PESKAITIS ("GUARANTORS"), AND MILLER CAPITAL
          CORPORATION, STEPHEN A. MCCONNELL, JOCK PATTON AND DICKERSON
                               WRIGHT ("LENDERS")


For and in consideration of $1.00, and other good and valuable consideration
provided by each of the parties hereto to each of the others, including
agreement to the following terms and conditions, the parties hereto agree this
30th of December, 1999 that the following terms and conditions are incorporated
in and made a part of the Securities Purchase Agreement, Notes, Security
Agreements, Guaranties and other instruments and documents ("Loan Documents")
executed and delivered at any time from and after August 10, 1999 in connection
with the above-captioned Bridge Loan Transaction as well as that certain
Engagement Letter dated July 26, 1999 relating to investment advisory services
provided to Debtor by Miller Capital Corporation ("MCC").

         o  Debtor will pay Lenders $150,000.00 in cash on or before January 31,
            2000.

         o  Debtor will pay the remaining principal balance of $600,000.00, plus
            interest at the rate of 12% per annum, in monthly payments of
            interest only for 6 months beginning March 1, 2000 and continuing on
            the 1st day of each month thereafter.

         o  Debtor will pay the remaining principal balance of $600,000.00, plus
            any accrued interest, on August 1, 2000, provided the Debtor has
            received debt or equity financing proceeds in an aggregate amount of
            $3,000,000 or more during the period commencing December 30, 1999
            and continuing through August 1, 2000, and limited to the extent
            such proceeds exceed $3,000,000. Any debt or equity financing
            proceeds received in an aggregate amount of less than $3,000,000.00
            during this period will be used for operations.

         o  If the Debtor has not received debt or equity financing proceeds in
            an aggregate amount of $3,600,000 or more during the period
            commencing December 30, 1999 and continuing through August 1, 2000,
            the Debtor will pay the remaining principal balance of $600,000.00,
            plus interest at the rate of 12% per annum, in six equal monthly
            payments of principal and interest beginning on August 1, 2000 and
            continuing on the 1st day of each month thereafter. Any debt or
            equity financing proceeds received after August 1, 2000, to the
            extent in excess of $3,000,000, will be applied first to payment in
            full of outstanding principal and interest to the Lenders.

         o  The Debtor will issue 300,000 shares of common stock to MCC for
            $1.00 of consideration with regard to termination of the Engagement
            Letter and 250,000 shares of common stock, for $1.00 of
            consideration, to Lenders in connection with the Loan Documents.



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         o  The Engagement Letter will terminate on December 30, 1999 and
            neither party thereto will have any continuing duty or obligation to
            the other, except that Debtor will pay a fee to MCC pursuant to the
            fee schedule set forth therein out of the proceeds, if any, received
            by Debtor from any equity or debt financing or investment by any of
            the parties introduced to Debtor by MCC and identified in the
            schedule attached hereto.

         o  MCC and the other Lenders will not subordinate any of the existing
            security interests and guarantees in favor of MCC and Lenders under
            the Loan Documents to any lender or investor ("New Lender") that at
            any time hereafter provides equity or debt financing or investment
            to Debtor, but hereby consents to and agrees to permit Debtor to
            incur any such new financing or investment with the grant of a
            security interest to such New Lender in and to any and all
            collateral under the Loan Documents, which security interest shall
            be pari passu with the Lender's debt, provided that: (i) the terms
            of such new debt provide that no principal payments can be made on
            the new debt until the Lender's debt has been repaid in full; and
            (ii) the amount of such new debt does not exceed $1,500,000. Lenders
            all agree to enter into a collateral sharing arrangement with such
            New Lender, pursuant to which the collateral currently securing the
            debt of the Lenders would also be permitted to secure the debt of
            the New Lender on a pari passu basis.

ACCEPTED AND AGREED THIS 30th day of December 1999.


On Behalf of MCC and Lenders:                     On Behalf of Debtor:

Miller Capital Corporation, Inc.                  LEXON Technologies, Inc.

By: /s/ Rudy P. Miller                            By: /s/ Steven Peskaitis
    --------------------------------                 ---------------------------
        Rudy P. Miller, CEO                               Steven Peskaitis,
                                                          President


                                                  On Behalf of Guarantors:

                                                  Chicago Map Corporation

                                                  By:  /s/ Steven Peskaitis
                                                     ---------------------------
                                                           Steven Peskaitis,
                                                           President



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