Document:

<PAGE>

                         [TRAMMELL CROW COMPANY LOGO]

                                                                  EXHIBIT 10.8.3

September 15, 1999

Sophie Tschosik
ClearCommerce
11500 Metric Blvd.
Suite 300
Austin, TX 78758

Re:  Expansion into 3,946 square feet at Braker M-2

Dear Sophie:

Please let this letter serve to document our understanding that you will accept
and will occupy the facility at 11500 Metric Blvd., Suite 250, Austin, Texas,
effective October 1, 1999. Under the terms of our Lease Agreement, dated July
19, 1999, the rental and any other monthly expenses, such as operating expenses,
utility and security costs, if any, for the facility accrue from October 1,
1999. Commencement date of the lease term shall be established as October 1,
1999, and the expiration date shall be established as shown on the Lease
Agreement.

Please be advised that power will be discontinued in Lessor's name within three
(3) days of occupancy and that a representative of your firm should contact the
Electric Company to make appropriate arrangements as soon as possible.

Please indicate your acceptance of the above by signing all three (3) copies of
this letter, maintaining one (1) copy for your files and returning two (2)
copies to this office.

Sincerely,

TRAMMELL CROW CENTRAL TEXAS, LTD.

                                       AGREED AND ACCEPTED:

                                       By:         [ILLEGIBLE]
                                          ------------------------------
                                       Title:   Vice President, [ILLEGIBLE]
                                             ---------------------------
                                       Date:          9/30/00
                                            ----------------------------

CC:  Rebecca Nixon
     Connie Shelton<PAGE>

                             [TRAMMELL CROW LOGO]

                                                                  EXHIBIT 10.8.4

10/19/1999

Clear Commerce
Sophie Tschosik
Fax # 512-832-8901

Sophie,

Per our conversation from this morning; I have broken down your rent roll for
you. If you have any questions or concerns, please feel free to call me and I
will forward you to the right contact.

As of October 1, 1999 your rent roll will be:   Base Rent..............23,296.50
                                                Insurance.................194.11
                                                Mgmt Fees...............1,171.38
                                                Operating Expenses......1,535.91
                                                Property Tax............3,084.98

                                                Total..................29,282.88

Also, just as another reminder that your outstanding amount for October is
4,176.54. Please remit this payment as soon as possible.

Thank You,

/s/ JOANN TENEYUEA                      On Our Way to
                                    One Million Merchants
JoAnn Teneyuca
Associate Accountant
Trammell Crow Company                   THIS IS RENT FOR
512-320-5599                          ALL 3 SUITES COMBINED<PAGE>

                                                                 EXHIBIT 10.8.5

                  THIRD AMENDMENT TO LEASE AGREEMENT BETWEEN
                CFH-FTAX LIMITED PARTNERSHIP, AS LANDLORD, AND
                     CLEARCOMMERCE CORPORATION, AS TENANT

       To be attached to and form a part of Lease made on or about the
       4th day of November, 1998 (which together with any amendments,
       modifications and extensions thereof, is hereinafter called the
       Lease), between Landlord and Tenant, covering a total of 28,722
       square feet and located at 11500 Metric Boulevard, Suites 250,
       300, and 410, Austin, Texas, known as Braker M-2, Braker M-3,
       and Braker M-4.

     WITNESSETH, THAT:
     WHEREAS, by Agreement of Lease dated November 4, 1998, Landlord leased to
Tenant certain space containing approximately 28,722 square feet in the
buildings located at 11500 Metric Boulevard, Suites 250, 300, and 410, Austin,
Texas, and
     WHEREAS, Tenant needs additional space for its business purposes and
Landlord has available an area adjacent hereto.
     NOW, THEREFORE, in consideration of the premises, Landlord and Tenant
covenant and agree as follows:
     1.   Effective March 1, 2000, the demised premises shall contain, in
addition to the approximately 28,722 square feet originally demised ("Original
Space"), an additional area, hereinafter called the "Expansion Space",
containing approximately 6,300 square feet (Suite 495, Braker M-4) adjacent
thereto (see Exhibit "A" attached hereto), thus making the aggregate area of the
demised premises approximately 35,022 square feet.  The Term for the Suites 300
and 410 shall end on January 31, 2002, and the Term for the Suites 250 and 495
shall end on September 30, 2002.  Except for where noted below, Tenant shall
accept the Expansion Space in its current "as is" condition and all improvements
must comply with Landlord's Standards and Specifications for Office/Warehouse
                            -------------------------------------------------
Buildings.
---------
     2.   Effective March 1, 2000, the monthly base rental shall be

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------
                         Monthly Base Rent        Monthly Base Rent        Total Monthly Base Rent       Total Monthly
                         Suites 300 & 410             Suite 250                  Suite 495                Base Rental
------------------------------------------------------------------------------------------------------------------------
<S>                      <C>                      <C>                      <C>                           <C>
3/1/00 - 1/31/02            $20,501.00                $3,354.10                  $5,670.00                $29,525.10
------------------------------------------------------------------------------------------------------------------------
2/1/02 - 9/30/02               N/A                    $3,354.10                  $5,670.00                $ 9,024.10
------------------------------------------------------------------------------------------------------------------------
</TABLE>

plus property taxes, common area maintenance, management fees and insurance as
provided in the Lease, payable on the first day of each month during the balance
of the term.
     3.   Tenant, at Tenant's expense, may install voice and data lines between
the Expansion Space and Original Space. These improvements must comply with
Trammell Crow Company's standard specifications (see Standards and
                                                     -------------
Specifications for Office/Warehouse Buildings) and all applicable governmental
---------------------------------------------
regulations. Prior to beginning construction of any such improvements, Tenant
shall submit architectural drawings of the proposed improvements to Landlord and
shall obtain Landlord's written consent to begin construction.
     4.   Landlord shall put the Expansion Space HVAC system in good working
order prior to March 1, 2000 and warranty the same until May 31, 2000 provided
that Tenant enters into a regularly scheduled maintenance/service contract as
required in the Lease.
     5.   Landlord shall ensure that previous tenant's sign is removed from the
Building fascia surface and such fascia surface is repaired, if necessary.
     6.   WITNESSETH that the Lease expressly refers to Landlord as CFH-FTAX
Limited Partnership.  The Landlord's name has been changed to Crow Family
Holdings Industrial Texas Limited Partnership, a Delaware Limited Partnership.
The Lease and all related documents are hereby amended such that all references
to "Landlord" or "CFH-FTAX Limited Partnership" will translate to mean "Crow
Family Holdings Industrial Texas Limited Partnership, a Delaware Limited
Partnership".
     7.   Except as herein and hereby modified and amended the Agreement of
Lease shall remain in full force and effect and all the terms, provisions,
covenants and conditions thereof are hereby ratified and confirmed.

DATED AS OF THE  23rd   DAY OF   February, 2000.
                -------        ----------  ----

WITNESS:                 Crow Family Holdings Industrial Texas Limited
                         Partnership, a Delaware Limited Partnership:
                         By:   CFH-FTGP, L.L.C., a Delaware limited
                               liability company, its sole general partner
                         By:   Crow Family Holdings Industrial Limited
                               Partnership, a Delaware limited partnership,
                               its sole member
                         By:   CFH Industrial Trust, Inc., a Maryland
                               corporation, its sole general partner

/s/ [illegible]          /s/  JEANNA K. CAMP
---------------------    --------------------------------------------------
                         By:  Jeanna K. Camp
                         --------------------------------------------------
                         Title:  Vice-President
                         --------------------------------------------------

WITNESS:                 ClearCommerce Corporation:

                         [illegible]
---------------------    --------------------------------------------------
                         By:  [illegible]
                         --------------------------------------------------
                         Title:  CFO
                         --------------------------------------------------<PAGE>

                                                                  EXHIBIT 10.9.3

                                THIRD AMENDMENT
                                      TO
                     CREDIT AGREEMENT AND PROMISSORY NOTE

        This Third Amendment to Credit Agreement and Promissory Note (the
"Amendment") is entered into as of June 22, 2000 by and between IMPERIAL BANK
("Bank") and CLEARCOMMERCE CORPORATION ("Borrower").

                                   RECITALS
                                   --------

        Borrower and Bank are parties to that certain Credit Agreement and
Promissory Note dated as of July 20, 1999 (the "Agreement"). The parties desire
to amend the Agreement in accordance with the terms of this Amendment.

        NOW, THEREFORE, the parties agree as follows:

        1.   The Paragraph of the Promissory Note entitled Payment is hereby
             amended in full to read as follows:

"PAYMENT, Borrower will pay this loan in accordance with the following payment
schedule:

Advances under this Note shall be available through July 31, 2000 (the "Draw
Period"). During the Draw Period, interest only shall be due on the last day of
each month beginning August 31, 1999. On July 31, 2000, the then outstanding
principal balance of the advances under this Note shall be payable in 24 equal
monthly payments of principal plus accrued interest payable on the last day of
each month beginning August 31, 2000. All principal and accrued but unpaid
interest shall in any event be due and payable on or before July 31, 2002.
Principal amounts advanced under this Note and repaid may not be reborrowed.

        2.   Unless otherwise defined, all capitalized terms in this Amendment
shall be as defined in the Agreement. Except as amended, the Agreement remains
in full force and effect.

        3.   Borrower represents and warrants that the Representations and
Warranties contained in the Agreement are true and correct as of the date of
this Amendment, and that no Event of Default has occurred and is continuing.

        4.   This Amendment may be executed in two or more counterparts, each
if which shall be deemed an original, but all of which together shall
constitute one instrument.

        5.   As a condition to the effectiveness of this Amendment, Bank shall
have received, in form and substance satisfactory to Bank, the following:

                a)   this Amendment, duly executed by Borrower;

                b)   such other documents, and completion of such other matters,
                     as Bank may reasonably deem necessary or appropriate.

IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the first
date above written.

Signatures appear on next page.

<PAGE>

                                        CLEARCOMMERCE CORPORATION

                                        By:  /s/ Michael Grajeda
                                             ----------------------
                                        Title:   CFO
                                            -----------------------

                                        IMPERIAL BANK

                                        By:  /s/ [ILLEGIBLE]
                                             ----------------------
                                        Title:   AVP
                                             ----------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}], [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}], [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}]]