<PAGE>

                                                                   EXHIBIT 10.25

                                           *** Text Omitted and Filed Separately
                                               Confidential Treatment Requested
                                                 Under 17 C.F.R. (S)(S)
                                                 200.80(B)(4), 200.83 AND
                                                          240.24B-2


    CyberSource On-Demand Commerce Applications(TM) and Services Agreement


     This CyberSource On-Demand Commerce Applications and Services Agreement
(the "Agreement") is entered into by and between CyberSource Corporation, a
Delaware corporation ("CyberSource"), and Mercata, Inc., a Delaware corporation
("Customer").

     Customer desires to obtain and CyberSource is willing to supply certain
services on the terms and subject to the conditions set forth in this Agreement.

     For good and valuable consideration, the receipt and adequacy of which are
hereby acknowledged, CyberSource and Customer hereby agree as follows:

1.   Certain Definitions
     -------------------

The following definitions shall apply to this Agreement.

a)   "Confidential Information."  Any data or information, oral or written,
treated as confidential that relates to either party's (or, if either party is
bound to protect the confidentiality of any third party's information, such
third party's) past, present, or future research, development or business
activities, including any unannounced products and services, any information
relating to services, developments, inventions, processes, plans, financial
information, forecasts, and projections and the financial terms of this
Agreement. Notwithstanding the foregoing, Confidential information shall not be
deemed to include information if: (i) it was already known to the receiving
party prior to the date of this Agreement as established by documentary
evidence; (ii) it is in or has entered the public domain through no breach of
this Agreement or other wrongful act of the receiving party; (iii) it has been
rightfully received by the receiving party from a third party and without breach
of any obligation of confidentiality of such third party to the owner of the
Confidential Information; (iv) It has been approved for release by written
authorization of the owner of the Confidential Information; (v) it has been
independently developed by a party without access to the Confidential
Information of the other party; or (vi) it is required to be disclosed pursuant
to final binding order of a governmental agency or court of competent
jurisdiction, provided that the owner of the Confidential Information has been
given reasonable notice of the pendency of such an order and the opportunity to
contest it.

b)   "Intellectual Property." All (i) copyrights (including, without limitation,
the right to reproduce, distribute copies of, display and perform the
copyrighted work and to prepare ____ works; copyright registrations and
applications, trademark rights (including, without limitation, registrations and
applications), patent rights, trade names, mask-work rights, trade secrets,
moral rights, author's rights, privacy rights, publicity rights, algorithms,
rights in packaging, goodwill and other proprietary rights, and all renewals and
extensions thereof, regardless of whether any of such rights arise under the
laws of the United States or any other state, country or jurisdiction, (ii)
intangible legal rights or interests evidenced by or embodied in any idea,
design, concept, technique, Invention, discovery, enhancement or improvement,
regardless of patentability, but including patents, patent applications, trade
secrets, and know-how; (iii) all derivatives of any of the foregoing.

c)   "On-Demand Commerce Applications(TM) and Services." Those products and
services of CyberSource to be provided to Customer hereunder (collectively the
"Services").

d)   "Products."  Those products, content and/or services that Customer purports
to own or have rights to for which the Services of CyberSource will be rendered
under this Agreement.

e)   "Account."  Customer identification created and maintained in the
CyberSource system to enable Customer's use of ON-DEMAND COMMERCE
APPLICATIONS(TM) and Services.

2.   Services and Fees
     -----------------

a)   CyberSource shall provide Customer with the service(s) selected below:

[ ] Easy Start(TM) Implementation        _______ (Customer's Initials)

[X] SCMP Implementation (Enterprise)     /s/ JCE (Customer's Initials)
                                         -------

[ ] Global Rights Registry               _______ (Customer's Initials)

[ ] Other_______________                 _______ (Customer's Initials)


b)   Customer may add (an) additional Service(s) by submitting a Service
Enhancement Request that shall be incorporated into this Agreement. Services
added subsequently to the execution of this Agreement will be provided to
Customer at the then current price.

c)   CyberSource will deliver to Customer an Invoice for Services rendered
during the billing period in the amounts set forth in the Price Annex to this
Agreement on or near the fifteenth (15th) calendar day of each month following
the month in which the Services are provided. Customer shall remit the amount(s)
due under the invoice no later than thirty (30) calendar days from the date of
said invoice.

d)   Interest shall accrue at the lesser of 1.0% per month or the maximum amount
permitted by applicable law for any fees that remain unpaid more than thirty
(30) calendar days past the date of the applicable invoice.

e)   CyberSource shall be entitled to revise any and all of the aforesaid fees
provided that CyberSource gives written notice to Customer at least sixty (60)
calendar days prior to the effective date of the fee change.

f)   Except as otherwise provided in his Agreement, Customer hereby grants
CyberSource such royalty-free, limited, non-exclusive right, authorization, and
license to Customer's Intellectual Property as necessary in connection with the
Products to perform the Services for Customer in accordance with this Agreement.

3.   Term and Termination
     --------------------

a)   The initial term of this Agreement shall be one (1) year beginning from the
Effective Date. Thereafter, this Agreement will renew automatically for
additional terms of one (1) year ("Additional Term") unless either party
provides written notice to the other party at least thirty (30) days prior to
any such renewal that the Agreement shall not so renew.

b)   The Agreement may be terminated by either party at any time in the event of
a material breach by the other party that remains uncured after thirty (30)
calendar days written notice thereof. The parties acknowledge that nonpayment of
fees constitutes a material breach of this Agreement.

c)   Notwithstanding any provision in this Agreement to the contrary, this
Agreement may be terminated by either party at any time without cause with sixty
(60) days prior written notice thereof.

d)   In the event that CyberSource reasonably believes that Customer's conduct
or its Products violate applicable law, injure the reputation of CyberSource, or
pose a threat to CyberSource's systems, equipment, processes, or Intellectual
Property (the "Offending Condition"), CyberSource may suspend providing the
Services to Customer with one (1) day prior written notice and thereafter may
terminate this Agreement without notice if the offending condition remains
uncured more than thirty (30) calendar days after said notice.

e)   The Agreement may be terminated by either party effective immediately and
without any requirement of notice, in the event that (i) the other party files a
petition, in bankruptcy, seeking any reorganization, arrangement, composition,
or similar relief under any law regarding insolvency or relief for debtors, or
makes an assignment for the benefit of creditors' (ii) a received, trustee, or
similar officer is appointed for the business or property of such
<PAGE>

party; (iii) any involuntary petition or proceeding, under bankruptcy or
insolvency laws, is instituted against such party and not stayed, enjoined, or
discharged within sixty (60) days; or (iv) the other party adopts a resolution
for discontinuance of its business or for dissolution.

f)   Except as otherwise provided in this Agreement, within five (5) business
days of termination of this Agreement, each of the parties shall return to the
other party all materials belonging to the other party that constitutes said
party's Confidential Information and/or Intellectual Property.

4.   Intellectual Property
     ---------------------

a)   Except as expressly set forth in this Agreement, neither party will acquire
any right, title, or interest in the other's Intellectual Property. Except as
otherwise provided in this Agreement, CyberSource agrees that as between
CyberSource and Customer all right, title, and interest in any Products provided
to CyberSource under this Agreement shall remain with Customer. Except as
otherwise provided in this Agreement, Customer agrees that as between
CyberSource and Customer all Intellectual Property originally created by
CyberSource and its authorized agents and/or contractors in connection with this
Agreement, including, without limitation, all fraud, export and other screening
histories, and all documentation (in any and all media), renewals and extensions
thereof, shall be entirely CyberSource's property, free of any claims whatsoever
by Customer.

b)   Should Customer use CyberSource's Global Rights Registry(TM) Services to
manage Customer's Intellectual Property, CyberSource will exercise commercially
reasonable efforts to protect such Intellectual Property while under
CyberSource's care.


5.   Confidential Information
     ------------------------

a)   Each party ("Receiving Party") agrees that any Confidential Information
received from the other party ("Disclosing Party") (i) shall not be used except
as necessary to perform the obligations required under this Agreement, (ii)
shall be disclosed only to those of its employees as are necessary for the
purposes hereunder, (iii) shall not be disclosed to third parties without the
written consent of the Disclosing Party during the term of this Agreement and
three (3) years thereafter, and (iv) shall be kept in safe care as if would keep
its own, similar confidential information (which care shall not in any case be
less than reasonable).

b)   Upon termination of this Agreement, and except as otherwise provided in
this Agreement, each party shall promptly deliver to the other party all of the
other party's Confidential Information.

6.   Limitation of Liability
     -----------------------

a)   UNDER NO CIRCUMSTANCES (i) SHALL EITHER PARTY BE LIABLE TO THE OTHER PARTY
FOR INDIRECT, INCIDENTAL, CONSEQUENTIAL, SPECIAL OR EXEMPLARY DAMAGES (EVEN IF
THAT PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES), SUCH AS, BUT
NOT LIMITED TO, LOSS OF REVENUE, PROFITS OR BUSINESS, COSTS OF DELAY, COSTS OF
LOST OR DAMAGED DATA OR DOCUMENTATION, OR SUCH PARTY'S LIABILITIES TO THIRD
PARTIES ARISING FROM ANY SOURCE; OR (ii) SHALL CYBERSOURCE BE LIABLE TO CUSTOMER
WITH RESPECT TO ANY SUBJECT MATTER OF THIS AGREEMENT UNDER ANY CONTRACT,
NEGLIGENCE, STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR ANY AMOUNTS
IN EXCESS, IN THE AGGREGATE, OF FEES PAID TO CYBERSOURCE, HEREUNDER DURING THE
TWELVE-MONTH PERIOD PRIOR TO THE DATE THE CAUSE OF ACTION AROSE. THE EXCLUSIONS
AND LIMITATIONS OF THIS SECTION DO NOT APPLY TO LIABILITY ARISING FOR BODILY
INJURY OF A PERSON OR IN STATES THAT PROHIBIT THE EXCLUSION OR LIMITATION OF
INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LIMITATIONS ON THE DURATION OF AN IMPLIED
WARRANTY.

b)   Customer shall bear (i) all collection risk (including, without limitation,
credit card fraud and any other type of credit card fraud) with respect to sales
of its Products; and (ii) all responsibility and liability for the proper
payment of all taxes which may be levied or assessed, including, without
limitation, sales taxes.

c)   Customer is solely responsible for maintaining complete backup records of
all information relating to its customers' orders, inquiries and purchases and
any other customer information, once such information has been provided to
Customer by CyberSource.

d)   Both parties agree that CyberSource has no obligation to monitor or
regulate the content of the Products or to ascertain Customer's right to have
CyberSource perform the Services with respect to the Products under this
Agreement.

7.   Warranties
     ----------

a)   CyberSource hereby represents and warrants that the Services provided to
customer hereunder will conform substantially to specifications set forth and
contained in CyberSource marketing materials, the CyberSource website, and
support documentation provided to Customer by CyberSource.

b)   CyberSource hereby represents and warrants (i) that the Services do not
infringe the Intellectual Property rights of any third party; (ii) that any
software created by CyberSource to perform the Services hereunder is Year 2000
complaint, in that, it will accurately process, address, store, and calculate
date and time data from, into, and beyond the calendar years 1999, 2000, and
2001 A.D. including leap year calculations and that it will not produce abnormal
or invalid results or cease operations due to the change from calendar years
1999, 2000, 2001 A.D., and beyond; and (iii) that any software created and used
by CyberSource to perform the Services under this Agreement will be virus-free.

c)   Customer hereby represents and warrants (i) that the Products do not
infringe upon any third party Intellectual Property Rights and are not
defamatory, libelous, or obscene; (ii) that Customer has all necessary
authorizations to permit CyberSource to perform the Services with respect to the
Products; and (iii) that Customer has obtained all necessary governmental
permits, licenses, and authorizations for the distribution of the Products to
the territories, countries, and entities that are contained in instructions to
CyberSource.

EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, CYBERSOURCE HEREBY SPECIFICALLY
DISCLAIMS ANY REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THE
SERVICES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NON-INFRINGEMENT AND ANY IMPLIED WARRANTIES ARISING FROM
COURSE OR DEALING OR COURSE OF PERFORMANCE.

8.   Indemnification
     ---------------

a)   Subject to Section 6 of this Agreement, each Party (the "Indemnifying
Party") will defend at its expense any legal cause of action brought against the
other party (the "Indemnified Party"), to the extent that such cause of action
is based upon a claim that any services or products of the Indemnifying Party
provided hereunder infringe a copyright, United States patent, trade secret, or
other intellectual property rights of a third party (other than claims relating
to conducting internet commerce generally). The Indemnifying Party will pay
those costs and damages finally awarded against the Indemnified Party which are
attributable to any such claim, provided that (i) Indemnified Party notifies
Indemnifying Party in writing immediately after Indemnified Party becomes aware
of such claim or the possibility thereof, and, (ii) Indemnifying Party has sole
control of the settlement, compromise, negotiation, and defense of any such
action; and, (iii) Indemnified Party cooperates in good faith, in the defense of
any such legal action.

b)   Should any of Indemnifying Party's products or services become, or in
Indemnifying Party's opinion is highly likely to become, the subject of a

                                      2.
<PAGE>

claim of infringement, Indemnifying Party may, at its option, (i) obtain the
right for Indemnified Party to continue using the Services; (ii) replace or
modify the Indemnifying Party's products and services so it is no longer
infringing or reduces the likelihood that it will be determined to be
infringing, or (iii) if neither of the foregoing options is commercially
reasonable, terminate this Agreement, provided that Indemnifying Party refunds
any fees received from or remits any amounts due to Indemnified Party hereunder,
whichever applicable.

c)   Indemnifying Party shall have no liability for any claim of infringement
based on (i) products or services of the Indemnifying Party which have been
modified by parties other than Indemnifying Party; (ii) Indemnified Party's use
of Indemnifying Party's products or services in conjunction with data where use
with such data gave rise to the infringement claim; or (iii) Indemnified Party's
use of Indemnifying Party's products or services with non-Indemnifying Party
software or hardware, where use with such other software or hardware gave rise
to the infringement claim.

9.   Marketing
     ---------

CyberSource shall be entitled to disclose the existence of the relationship
formed hereunder between Customer and CyberSource through the use of media
releases, public announcements, and customer reference materials. CyberSource
agrees to use commercially reasonable efforts to coordinate the release of its
announcements in conjunction with related announcements of the other party.
Customer hereby grants CyberSource a limited, non-exclusive, non-transferable
royalty-free license to use its trademarks and service marks solely for the
issuance of media releases and public announcements; provided that CyberSource
agrees to change, at CyberSource's expense, any displays of Logos which Customer
reasonably determines to be a misuse of Licensor's Logos.

10.  Relationship of Parties
     -----------------------

The parties shall perform all of their duties under this Agreement as
independent contractors. Nothing in this Agreement shall be construed to give
either party the power to direct or control the daily activities of the other
party, or to constitute the parties as principal and agent, employer and
employee, franchiser and franchiseee, partners, joint venturers, co-owners, or
otherwise as participants in a joint undertaking. The parties understand and
agree that, except as specifically provided in this Agreement, neither party
grants the other party the power or authority to make or give any agreement,
statement, representation, warranty, or other commitment on behalf of the other
party, or to enter into any contract or otherwise incur any liability or
obligation, express or implied, on behalf of the other party, or to transfer,
release, or waive any right, title, or interest of such other party.

11.  Government Law; Consent to Jurisdiction
     ---------------------------------------

This Agreement will be deemed entered into in California and will be governed by
and interpreted in accordance with the laws of the State of California,
excluding (i) that body of law known as conflicts of law and (ii) the United
Nations Convention on Contracts for the International Sale of Goods. The parties
agree that any dispute arising under this Agreement, which is not subject to
Section 12 below, will be resolved in the state or federal courts in Santa Clara
County, California, and the parties hereby expressly consent to jurisdiction
therein.

12.  Arbitration
     -----------

a)   Except that the parties shall be entitled to apply to the courts for
mandatory or injunctive equitable relief, any controversy or claim arising out
of or relating to this Agreement, or the breach thereof, will be settled by
arbitration before three (3) arbitrators in accordance with the rules then
prevailing of the American Arbitration Association, and judgment upon the reward
rendered by the arbitrators may be entered in any court having jurisdiction
thereof. In any such proceeding the arbitrators shall make every reasonable
effort to resolve the matter expeditiously and to reduce the costs of the
proceeding, by limiting discovery and other means; and neither party shall be
entitled under any circumstances to receive punitive exemplary damages. Unless
the parties otherwise agree in writing, such arbitration shall be conducted in
San Jose, California, and the parties consent to jurisdiction and venue in the
courts of California located in Santa Clara County, California. Judgment of
arbitrator shall be final and binding. Each party hereto waives its right to an
appeal and/or a jury.

13.  Assignment
     ----------

This Agreement may not be transferred to assigned by either party without the
prior written consent of the other party, which consent shall not be
unreasonably withheld. Notwithstanding the foregoing, consent of the other party
shall not be required for assignment or transfer made by (i) operation of law or
(ii) to an entity that acquires substantially all of its stock, assets or
business.

14.  Employee Hiring
     ---------------

During the term of this Agreement and for six (6) months thereafter, neither
party shall directly solicit or recruit any employee or consultant of the other
party for itself or for any other company or individual, without the prior
written consent of the other party. Nothing in the foregoing sentence shall be
construed to prevent either party from hiring an employee of the other party
resulting from (i) advertising of open positions, participating in job fairs or
the like, or other forms of soliciting candidates for employment which are
general in nature or not directed specifically and solely at a given employee of
the other party, (ii) unsolicited inquiries about employment opportunities or
possibilities from headhunters or other agents acting for unidentified
principals, or (iii) unsolicited inquiries about employment opportunities from
any employee.

15.  Force Majeure
     -------------

Neither party hereto shall be responsible for any failure to perform its
obligations under this Agreement (other than obligations under Sections 4 and 5)
if such failure is caused by acts of God, war, strikes, revolutions, lack or
failure of transportation, facilities, laws or governmental regulations or other
causes that are beyond the reasonable control of such party. Obligations
hereunder, however, shall in no event be excused but shall be suspended only
until the cessation of any cause of such failure. In the event that such force
majeure should obstruct performance of this Agreement for more than thirty (30)
calendar days, the parties hereto shall consult with each other to determine
whether this Agreement should be modified or terminated. The party facing an
event of force majeure shall use reasonably commercial efforts to remedy that
situation as well as to minimize its effects. A case of force majeure shall be
notified to the other party by facsimile within five (5) days after its
occurrence and shall be confirmed by a letter.

16.  Entire Agreement
     ----------------

This Agreement constitutes and contains the entire agreement between the parties
with respect to the subject matter hereof and supersedes any prior oral or
written agreements. Each party acknowledges and agrees that the other has not
made any representations, warranties or agreements of any kind, except as
expressly set forth herein.

17.  Modifications, Amendments, and Waivers
     --------------------------------------

This Agreement may not be modified or amended, including by custom, usage of
trade, or course of dealing, except by an instrument in writing signed by duly
authorized employees of both of the parties hereto.

The waiver by either party of a breach of any provision contained herein shall
be in writing and shall in no way be construed as a waiver of any subsequent
breach of such provision or the waiver of the provision itself.

18.  Counterparts
     ------------
This Agreement may be executed in counterparts, including counterpart
transmitted by facsimile, each of which shall be deemed an original, and all
such counterparts shall constitute one and the same agreement.

19.  Survival
     --------

                                      3.
<PAGE>

The provisions of this Agreement relating to payment of any fees or other
amounts owed, payment of any interest on unpaid fees, confidentiality,
warranties, limitation of liability, and indemnity shall survive any termination
or expiration of this Agreement.

20.  Severability
     ------------

If any provision of this Agreement shall be held illegal or unenforceable, that
provision shall be limited or eliminated to the minimum extent necessary so that
this Agreement shall otherwise remain in full force and effect and enforceable.

21.  Headings
     --------

The headings in this Agreement are intended for convenience or reference and
shall not affect the Agreement's interpretation.

22.  Notices
     -------

Any notice, approval, request, authorization, direction or other communication
under this Agreement shall be given in writing at the address set forth below
and shall be deemed to have been delivered and given for all purposes (i) on the
delivery date, if delivered manually to the party to whom the same is directed;
(ii) one (1) business day after deposit with a commercial overnight carrier,
with written verification of receipt; and (iii) upon completion of transmission.
If sent via facsimile with a confirmation of successful transmission.

     In witness whereof, the parties have executed this Agreement, as of the
date last below written ("Effective Date").

CUSTOMER:

Attn:    _________________________________________________
Address: 110 - 110th Avenue, Suite 390
         Bellevue, WA 98004-5840
Phone:   425-468-9836                  Fax:   425-468-9936

By:      /s/ Jon Engman
         -------------------------------------------------
Name     Jon Engman           Title:  VP, Finance & Admin.
         ---------------------      ----------------------
E-mail:  jone@mercata.com
         -------------------------------------------------
Date:    3/29/99
         -------------------------------------------------

CYBERSOURCE CORPORATION
550 S. Winchester Boulevard, 3/rd/ Floor
San Jose, CA 95128-2545
(408) 556-9100        Fax: (408) 241-8270

By:      /s/ David Kim
         -------------------------------------------------
         (Signature of authorized CyberSource employee)

Name     David Kim                 Title:  Counsel
         --------------------------      -----------------
E-mail:  davidk@cybersource.com
         -------------------------------------------------
Date:    March 29th, 1999
         -------------------------------------------------

                                      4.
<PAGE>

                      First Amendment to the CyberSource
          On-Demand Commerce Applications(TM) and Services Agreement

The Agreement referenced above dated 3/29/99, by and between CyberSource
                                     -------
Corporation ("CyberSource"), and Mercata, Inc. ("Customer"), in consideration of
the mutual promises of the parties, is amended as follows:

1.   Section 2a.  The lines for "Global Rights Registry" and "Other" are
     ----------
deleted.

[...***...]*

3.   Section 2f.   The paragraph is deleted in its entirety.
     ----------

4.   Section 3d.  The paragraph is deleted in its entirety and replaced with the
     ----------
following:

"In the event that CyberSource reasonably believes that Customer's conduct or
its Products violate applicable law, inure the reputation of CyberSource, or
pose a threat to CyberSource's systems, equipment, processes, or Intellectual
Property (the "Threatening Condition"), CyberSource may suspend providing the
Services to Customer with ten (10) days prior written notice and thereafter may
terminate this Agreement without further notice if the Threatening Condition
remains uncured more than thirty (30) calendar days after said notice.
Notwithstanding the foregoing, CyberSource may suspend providing the Services to
Customer with one (1) day notice if the Threatening Condition, in CyberSource's
good faith and reasonable belief, is imminently and materially dangerous to
CyberSource's systems, equipment, processes, or intellectual Property, and
thereafter may terminate this Agreement without further notice if said
Threatening Condition remains uncured more than thirty (30) calendar days after
said notice."

5.   Section 6a.  Subpart (ii) of the paragraph is deleted and replaced with the
     ----------
following:

"(ii) SHALL EITHER PARTY BE LIABLE TO THE OTHER WITH RESPECT TO ANY SUBJECT
MATTER OF THIS AGREEMENT UNDER ANY CONTRACT, NEGLIGENCE, STRICT LIABILITY OR
OTHER LEGAL OR EQUITABLE THEORY FOR ANY AMOUNTS IN EXCESS, IN THE AGGREGATE, OF
FEES PAID TO CYBESOURCE HEREUNDER DURING THE TWELVE-MONTH PERIOD PRIOR TO THE
DATE THE CAUSE OF ACTION AROSE."

6.   Section 9.
     ---------

The following phrase shall be added to the end of the first sentence:

", provided that it has secured prior written consent from the Customer on each
usage."

The second sentence is deleted and replaced with the following:

"Neither party shall issue any press releases without the written consent of the
other party."

7.   Section 11.  The last sentence of the paragraph is deleted in its entirety.
     ----------

___________________________
* Confidential Treatment Requested
<PAGE>

8.   Section 12. The third sentence of the paragraph is deleted in its entirety.

9.   All other provisions of the Agreement remain unchanged.

UNDERSTOOD AND AGREED:
CYBERSOURCE CORPORATION                      MERCATA, INC.

Signature: /s/ David J. Kim                  Signature: /s/ Jon Engman
          -----------------------                      -------------------------

Printed Name: David J. Kim                   Printed Name: Jon Engman
             --------------------                         ----------------------

Title: Counsel                               Title: VP, Finance & Admin.
      ---------------------------                  -----------------------------

Date: March 29,1999                          Date: 3/29/99
     ----------------------------                 ------------------------------

                                      6.
<PAGE>

         On-Demand Commerce Applications (TM) & Services    U.S. Price Annex BS1
                                                                            2/99

<TABLE>
------------------------------------------------------------------------------------------------------------------------------------
On-Demand Commerce Applications
------------------------------------------------------------------------------------------------------------------------------------
<S>                                                    <C>       <C>      <C>      <C>       <C>       <C>       <C>       <C>
Monthly Minimum Transaction Commitment $ 95
                                          Volume Tier   Base      1        2        3         4         5         6         7
                                                       -----------------------------------------------------------------------------
                               Minimum Monthly Volume        0     1,001    3,001     7,501     15,001    30,001    50,001   75,001
                                                       -----------------------------------------------------------------------------
                               Maximum Monthly Volume    1,000     3,000    7,500    15,000     30,000    50,000    75,000
                                                       -----------------------------------------------------------------------------
                                     Discount Applied        0%        5%      10%       15%        25%       30%       35%      45%
------------------------------------------------------------------------------------------------------------------------------------
Order
------------------------------------------------------------------------------------------------------------------------------------
GeoPay(TM) (US $)                       Authorization   $0.100    $0.095   $0.090    $0.085     $0.075    $0.070    $0.065   $0.055
------------------------------------------------------------------------------------------------------------------------------------
                                           Settlement   $0.070    $0.067   $0.063    $0.060     $0.053    $0.049    $0.046   $0.039
------------------------------------------------------------------------------------------------------------------------------------
                                               Credit   $0.100    $0.095   $0.090    $0.085     $0.075    $0.070    $0.065   $0.055
------------------------------------------------------------------------------------------------------------------------------------
IVS TM  fraud screen                                    $0.390    $0.371   $0.351    $0.332     $0.293    $0.273    $0.254   $0.215
------------------------------------------------------------------------------------------------------------------------------------
Delivery Address Verification                           $0.120    $0.114   $0.108    $0.102     $0.090    $0.084    $0.078   $0.066
------------------------------------------------------------------------------------------------------------------------------------
GlobalTax (TM) (United States and Canada)               $0.120    $0.114   $0.108    $0.102     $0.090    $0.084    $0.078   $0.066
------------------------------------------------------------------------------------------------------------------------------------
TerritoryManager(TM) Includes U.S. Government Export    $0.120    $0.114   $0.108    $0.102     $0.090    $0.084    $0.078   $0.066
 Compliance  check.  Denied Parties List check and
 Merchant-defined territory restrictions.
------------------------------------------------------------------------------------------------------------------------------------

------------------------------------------------------------------------------------------------------------------------------------
NOTIFY EDI                                              Quote
------------------------------------------------------------------------------------------------------------------------------------
NOTIFY email/FTP pull                                  $0.290    $0.276    $0.261    $0.247     $0.218    $0.203    $0.189    $0.160
------------------------------------------------------------------------------------------------------------------------------------

------------------------------------------------------------------------------------------------------------------------------------
SmartCert(TM) Fee charged for each valid Sm@rtCert     $0.500    $0.475    $0.450    $0.425     $0.375    $0.350    $0.325    $0.275
certificate  ("Tab") issued based on the number of
access rights issued (product quantity) on each
certificate.  Includes issuance, subsequent validation
and U.S. Government export compliance.  Issuance of    $0.200    $0.190    $0.180    $0.170     $0.150    $0.140    $0.130    $0.110
promotional Sm@rtCert Tab. e.g.. those not containing
a x.509 certificate not requiring validation after
issuance.
------------------------------------------------------------------------------------------------------------------------------------
Digital Download                                       $0.350    $0.350    $0.350    $0.350     $0.350    $0.350    $0.350    $0.350
for digital warehousing and rights management services
see the CyberSource Global Rights Registry price
schedule
------------------------------------------------------------------------------------------------------------------------------------
Cancel/Return License or Key                           $ 0.50    $ 0.50    $ 0.50    $ 0.50     $ 0.50    $ 0.50    $ 0.50    $ 0.50
cancels electronic issued license for returned products
 Global Rights Registry service fees may also apply
------------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------------
Note: transaction pricing is based on total monthly use of all On-Demand Commerce Applications
------------------------------------------------------------------------------------------------------------------------------------
Account Setup and 60 Day Implementation Support
------------------------------------------------------------------------------------------------------------------------------------
 Enterprise Set Up includes GlobalTax, GeoPay, IVS, Delivery Address Verification, Territory Manager, supports one           $ 5.495
 CyberSource Merchant ID.  Assigned Merchant Support Engineer. 1hr remote project briefing; 1 day on-site customer
 support Training (trave. And lodging not included) 7x24 technical support (1hr response during business hours,
 on-call non-business hours).
 Includes access to the Merchant Support site and associated tools.

 Project Set Up includes GlobalTax, GeoPay, IVS, Delivery Address Verification, Territory Manager, supports one...........   $ 2,495
 CyberSource  Merchant ID, 1 hr. orientation call; and toll-free access to the merchant support center
 (email or 800#) M-F 7am-7pm PST  (2hr response commitment). Includes access to the Merchant Support Site and
 associated tools.
                                                                                                        Merchant"s Initials*:/s/ JCE
                                                                                                                             -------
</TABLE>

*By initialing each page of this Annex, Merchant understands that all of the
described services are available to Merchant but that Merchant is free to
utilize only those of the services suitable to Merchant, unless the service, by
its nature, requires the utilization of another service (C) 1999 CyberSource
Corporation
<PAGE>

           On-Demand Commerce Applications(TM) & Services   U.S. Price Annex BSI
                                                                            2/99

<TABLE>
------------------------------------------------------------------------------------------------------------------------------------

Single Application Options
------------------------------------------------------------------------------------------------------------------------------------
<S>                                                                                  <C>                                      <C>
 Setup additional terminal IDs (each)                                                                                        $  495

 NOTIFY fulfillment messaging setup for email or FTP pull (each warehouse required)                                          $  995
 NOTIFY EDI setup and configuration                                                                                           Quote

 SmartCert digital fulfillment setup                                                                                         $1,495
------------------------------------------------------------------------------------------------------------------------------------
 Ongoing Support Packages
------------------------------------------------------------------------------------------------------------------------------------
 Enterprise Support                                                                  $       995 per month, 12 month minimum
 Assigned Merchant Support Engineer, 7x24 technical support (1 hr response during
 business hours, on-call off-hours to assigned engineer or backup, response
 non-business hours). Includes online access to the Merchant Support site and
 associated tools.
 On-Demand Support
 Toll-free access to the merchant support center (email or 800#) M-F 7am-            $       295 per month, 12 month minimum
 7pm PST, 2hr response commitment.  Includes online access to the
 Merchant Support site and associated tools.
------------------------------------------------------------------------------------------------------------------------------------
 Per Incident Training and Support Services
------------------------------------------------------------------------------------------------------------------------------------
 On-Site Training                                                                    $ 1,000 per day
 Does not include travel expenses, one-day minimum.
 On-Site System Engineer Support                                                     $ 1,500 per day
 Does not include travel expenses, one-day minimum.
 System Engineer Support                                                             $   250 per day
 One hour minimum.  Remote support only.

                                                                                                       Merchant's Initials*: /s/ JCE
                                                                                                                            --------
</TABLE>

*By initialing each page of this Annex, Merchant understands that all of the
described services are available to Merchant but that Merchant is free to
utilize only those of the services suitable to Merchant, unless the service, by
its nature, requires the utilization of another service (C) 1999 CyberSource
Corporation.
<PAGE>

<TABLE>
         Mercata, Inc.                                                     Purchase Order No. 2082
         110- 110th Ave. NE
         Suite 390
         Bellevue, WA 98004-5840
                                                                                     Purchase Order


                  To: CyberSource Corp.                                Ship To:  Mercata, Inc.
                      550 S. Winchester Blvd.                                    110 - 110th Ave. NE
                      Third Floor                                                Suite 390
                      San Jose, CA 95128-2545                                    Bellevue, WA 98004-5840

------------------------------------------------------------------------------------------------------------------------------------
       [Illegible]              [Illegible]                    [Illegible]                             [Illegible]
------------------------------------------------------------------------------------------------------------------------------------
         03/29/99                                                Origin                                 3. Net 30
------------------------------------------------------------------------------------------------------------------------------------
       [Illegible]              [Illegible]        [Illegible]
------------------------------------------------------------------------------------------------------------------------------------
          Pete C.                 Prepaid              ASAP
------------------------------------------------------------------------------------------------------------------------------------
QTY [Illegible]     [Illegible]                                   Description                 [Illegible]           Amount
------------------------------------------------------------------------------------------------------------------------------------
<S>                              <C>                                                           <C>                       <C>
         1                          Enterprise Set Up                                            5495.00                   5495.00
                                                                                                      Total                5495.00
</TABLE>

                                                        /s/ Peter Crouch
                                                       -------------------------
                                                            Authorized Signature