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                                                                  EXHIBIT 10.7.3

                                  ADDENDUM C
                                    TO THE
                         LICENSE AND SERVICE AGREEMENT
                   BY AND BETWEEN CARDSERVICE INTERNATIONAL
                         AND CLEARCOMMERCE CORPORATION
                              DATED JUNE 30, 1998

WHEREAS, Cardservice International, Inc. ("CSI") and ClearCommerce Corporation
("CCC") have entered into a License and Service Agreement dated June 30, 1998
(the "Agreement"), a first amendment in a letter form identified as "Addendum
A", dated December 31, 1998, and a second amendment identified as "Addendum B"
on March 5, 1999; AND

WHEREAS, CSI and CCC desire to amend the Agreement, as amended by Addendum A and
B, with this Addendum C;

NOW THEREFORE, in consideration of the mutual covenants contained herein, CSI,
and its wholly owned subsidiary LinkPoint International, Inc. ("Customer") and
CCC hereby agree to amend the Agreement, as amended by Addendum A and B, as
follows:

1)  Section 2.  Delete the last sentence and replace that sentence with the
    ---------
following:

"During a period of [*] after the Effective Date of this Addendum C, Customer
shall [*] market and promote all current and future CCC products ("CCC
Products") and shall [*] the Licensed Products for i) [*] of Customer's internet
merchants, including all direct internet merchants and all indirect internet
merchants of Customer that are served through third parties [*], but excluding
internet merchants or their affiliated third party gateway operators [*] where
such excluded internet merchants and gateway operators only receive merchant
accounts (including merchant IDs) from CSI and where (a) Customer makes a good
faith effort to convert such excluded internet merchants and gateway operators
to the Customer's gateway, or (b) Customer makes a good faith effort to actively
promote and market CCC Products to such excluded internet merchants and gateway
operators, ("Merchants"); ii) [*] Merchants that use the Customer's gateway, as
measured on a quarterly basis, meaning that Customer will not utilize gateway
technology other than from CCC for the duration of the above mentioned [*].
Customer hereby grants to CCC a right of first refusal to have the Licensed
Products and the CCC Products used by Customer under the terms of this Agreement
for all new territories and markets throughout the world.

Customer agrees, during [*] period, to make available to CCC [*] (the "Customer
Data"), in a mutually agreed format. The Customer Data will be considered
Confidential Information

[*] Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

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as defined and protected in the existing Non-Disclosure Agreement between the
parties. The Customer Data will be gathered and provided electronically and in
batches by Customer as requested by CCC, but not more than [*]. If desired by
CCC, technology to implement real-time access to the Customer Data on Customer's
computer systems may be implemented, at the expense of CCC.

[*] Except as described herein, Customer retains its rights, ownership and
control of the disposition of the Customer Data. Data will be used for [*]
and if CCC wants to use it for any other reason, Customer written permission
must be granted.

As compensation for providing the Customer Data to CCC, during the [*], CCC will
pay Customer a [*] received by CCC for the sale of [*]

2) Section 5.  Delete the last sentence and replace with the following:
   ---------

"The term of the Product Support Services [*] unless either CCC or Customer
notifies the other party in writing at least [*] prior to expiration of the
Initial Term or the applicable annual Product Support Services renewal term.
However, CCC shall not unreasonably terminate renewal of the Product Support
Services."

3) Section 19.  Delete entire section and replace with the following:
   ----------

"Neither the License, this Agreement, nor any rights or responsibilities of
Customer or any of the assets held by or on behalf of Customer relating to this
Agreement, [*] may be assigned, sold, transferred, conveyed, or delegated to any
third party without [*]. Any attempted assignment, sale, conveyance, delegation
or transfer in violation of this section shall be void."

4) Add the following new section:

[*] Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

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"25. Survival.  All of the provisions of this Agreement shall survive any change
     --------
of control, merger, acquisition, sale, reorganization, or other corporate event
affecting either party, and all obligations hereunder shall apply to each of the
parties' subsidiaries, joint ventures, and affiliates."

5) Product and Pricing Schedule.  The parties confirm that the Initial Term [*].
   ----------------------------

Each Party hereto represents and warrants that (i) it has obtained all necessary
approvals, consents and authorizations to enter into this Agreement and to
perform and carry out its obligations hereunder, (ii) the persons executing this
Agreement on its behalf have express authority to do so, and, in so doing, to
bind the Party thereto; (iii) the execution, delivery, and performance of this
Agreement does not violate any provision of any bylaw, charter, regulation, or
any other governing authority of the Party; and (iv) the execution, delivery and
performance of this Agreement has been duly authorized by all necessary
corporate action and this Agreement is a valid and binding obligation of such
Party, and its subsidiaries, joint ventures, and affiliates, enforceable in
accordance with its terms.



IN WITNESS WHEREOF, the parties have entered into this Addendum C to the
Agreement as of the date of the last signature below, ("Effective Date").


CSI and LinkPoint International Inc.    ClearCommerce Corporation

By: /s/ CAESAR BERGER                   By: /s/ MICHAEL S. GRAJEDA
    -----------------------------           --------------------------------

Print Name: Caesar Berger               Print Name: Michael S. Grajeda
                                                    ------------------------
Title: Senior Vice President            Title: Chief Financial Officer
                                               -----------------------------

Date: March 6th, 2000                   Date: March 6, 2000
                                              ------------------------------

[*] Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

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