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                                                                   EXHIBIT 10.46

                          REPLACEMENT PROMISSORY NOTE
$125,000                                                        JANUARY 26, 2000



        FOR VALUE RECEIVED, William W. Dolan, Trustee of the Grace W. Duffey
Irrevocable Trust under Agreement dated January 26, 2000 promises to pay to
SmartGate, L.C., a Florida Limited Liability Company, 4400 Independence Court,
Sarasota, Florida 34234, the principal sum of One Hundred Twenty-Five Thousand
($125,000) Dollars, together with interest at the Applicable Federal Rate as
follows. Principal and interest shall be repaid on the first to occur of: (1)
five years from the date hereof, or (ii) the date on which the shares of
SmartGate, L.C. which are pledged as collateral hereunder are sold (with the
repayment under this subsection (ii) being at $1.00 of loan repayment for each
pledged share which is sold).

        This Promissory Note cancels and replaces Samuel S. Duffey's $125,000
payment obligation to SmartGate, L.C. in that certain Promissory Note dated
December 29, 1999, a cancelled copy of which is attached hereto. This
Replacement Promissory Note is being issued as part of Samuel S. Duffey's
exercise of a Stock Option and Assignment of the 125,000 shares of SmartGate,
L.C. to William W. Dolan, Trustee of the Grace W. Duffey Irrevocable Trust under
Agreement dated January 26, 2000 in exchange for the execution of this
Replacement Promissory Note ("Assignment"). The shares being acquired by the
Grace W. Duffey Irrevocable Trust under Agreement dated January 26, 2000 upon
the Assignment are pledged to SmartGate, L.C. as collateral under this
Replacement Promissory Note. This Replacement Promissory Note is being issued
without recourse to the maker ("Borrower") and without personal liability or
personal repayment obligation of the Borrower. The sole recourse of SmartGate,
L.C. to collect principal and interest due under this Replacement Promissory
Note is against the shares of SmartGate, L.C. pledged as collateral hereunder.
This Replacement Promissory Note can be repaid by either: (i) U.S. currency; or
(ii) delivery of shares of SmartGate, L.C. (or SmartGate, Inc., a Nevada
corporation) at the valuation of $1.00 per share or the current market value
(bid Price) of said shares on the repayment date, whichever is greater.

        This Replacement Promissory Note is made and executed hereunder and is
governed by the laws of the State of Florida.

                                     Grace W. Duffey Irrevocable Trust under
                                     Agreement dated January 26, 2000


                                     /s/ WILLIAM DOLAN
                                     -----------------------------------------
                                     William Dolan, Trustee




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                                CANCELLED PROMISSORY NOTE



$375,000.00                                                    December 29, 1999




     FOR VALUE RECEIVED, Samuel S. Duffey promises to pay to SmartGate, L.C., a
Florida Limited Liability Company, 4400 Independence Court, Sarasota, Florida
34234, the principal sum of Three hundred seventy five Thousand ($375,000)
Dollars, together with interest at the Applicable Federal Rate as follows.
Principal and interest shall be repaid on the first to occur of: (i) five years
from the date hereof; or (ii) the date on which the shares of SmartGate, L.C.
which are pledged as collateral hereunder are sold (with the repayment under
this subsection (ii) being at $1.00 of loan repayment for each pledged share
which is sold).

     This Promissory Note is being issued as part of the exercise of a Stock
Option.  The shares being acquired by Borrower upon exercise of the Stock
Option are simultaneously being pledged to SmartGate, L.C. as collateral under
this Promissory Note.  This Promissory Note is being issued without recourse to
the maker ("Borrower") and without personal liability or personal repayment
obligation of the Borrower.  The sole recourse of SmartGate, L.C. to collect
principal and interest due under this Promissory Note is against the shares of
SmartGate, L.C. pledged as collateral hereunder.  This Promissory Note can be
repaid by either: (i) U.S. currency; or (ii) delivery of shares of SmartGate,
L.C. (or SmartGate, Inc., a Nevada corporation) at the valuation of $1.00 per
share or the current market value (bid price) of said shares on the repayment
date, whichever is greater.

     This Promissory Note is made and executed hereunder and is governed by
the laws of the State of Florida.



                                                  /s/ Samuel S. Duffey
                                               ---------------------------
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                    FILING SCHEDULE PURSUANT TO PARAGRAPH 2.
    INSTRUCTIONS TO ITEM 601 UNDER SECTION 229.601 EXHIBITS OF REGULATION S-K

         A Replacement Promissory Note substantially identical in all material
respects except for the date, Borrower and principal amount was executed by
Debra Finehout (as Borrower), dated December 29, 1999, in the principal amount
of $250,000.

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                                   ASSIGNMENT



        FOR VALUE RECEIVED, Samuel S. Duffey ("Assignor") hereby assigns,
transfers and delivers to William W. Dolan, Trustee of the Grace W. Duffey
Irrevocable Trust under Agreement dated the 26th day of January, 2000
("Assignee"), all of Assignor's right, title and interest in and to 125,000
membership units (shares) of SmartGate, L.C., a Florida limited liability
company.

        This Assignment is being made by Assignor in consideration of Assignee
executing a Replacement Promissory Note in the amount of $125,000 payable to
SmartGate, L.C. replacing the $125,000 portion of that certain Promissory Note
dated December 29, 1999 made by Assignor to SmartGate, L.C. This Assignment is
at the same price Assignor paid for the 125,000 shares being assigned hereby,
which represents consideration of fair market value.

        IN WITNESS WHEREOF, the parties have hereunto set their hands and seals
as of this 26th day of January, 2000


                                        ASSIGNOR:


                                        /s/ SAMUEL S. DUFFEY
                                        ----------------------------------------
                                        Samuel S. Duffey



<PAGE>

                    FILING SCHEDULE PURSUANT TO PARAGRAPH 2.
    INSTRUCTIONS TO ITEM 601 UNDER SECTION 229.601 EXHIBITS OF REGULATION S-K

        An Assignment substantially identical in all material respects was
executed as of December 29, 1999 to Debra Finehout as Assignee assigning 250,000
membership units (shares) of SmartGate, L.C.