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                                                                 Exhibit 10.18

CISCO SYSTEMS
    [LOGO]
   CAPITAL

March 17, 2000

Warren Talbot
Cmerun Inc.
1740 Massachusetts Ave.
Boxboro, MA 01719

Cisco Systems Capital Corporation ("CSC"), a wholly owned subsidiary of Cisco
Systems. Inc. ("Cisco Systems"), specializes in providing innovative finance
solutions for Cisco Systems products and services. We are pleased to present
this proposal ("Proposal") for the transaction described below:

LESSOR:                       Cisco Systems Capital Corporation

LESSEE:                       Cmerun Inc.

EQUIPMENT:                    Cisco Systems products, or other products
                              satisfactory to CSC, as presented in a quotation
                              from the Cisco Systems Sales Team or a Cisco Value
                              Added Reseller, in form satisfactory to CSC.

SOFT COSTS:                   "Soft Costs," such as freight, taxes, maintenance,
                              installation, and software may be included in or
                              financed by the lease, as approved by the Lessor
                              in its discretion.

PROPOSAL CREDIT               In the aggregate, up to $400,000.00, including
LINE:                         Soft Costs not to exceed 33% of the total of this
                              proposal credit line.

PROPOSAL CREDIT               All purchase orders for equipment under this
LINE UTILIZATION              Proposal Credit Line shall be submitted no later
PERIOD:                       than six months after the MLA is agreed upon by
                              both the Lessee and CSC or six months after this
                              Proposal is agreed upon by both the Lessee and
                              CSC, which ever date occurs later.

SHIP TO:                      Location within the U.S. as advised. The equipment
                              may not be shipped to or used in any jurisdiction
                              outside the U.S.

PARTIAL SHIPMENTS:            Please indicate at the bottom of this letter
                              whether Lessee will accept scheduling of partial
                              purchase order shipments. (If not,
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                              please note that Cisco Systems will retain
                              shipments until complete.)

LEASE TYPE:                   Leases with a term equal to or less than 47 months
                              are intended to be a true lease for tax and
                              commercial law purposes. Leases with a term equal
                              to or greater than 48 months are intended to be a
                              lease intended as security for tax and commercial
                              law purposes.

INTERIM RENT:                 There is no interim rent, and commencement of
                              rental payments will occur on the 1st of the month
                              on or after acceptance or deemed acceptance.

NET LEASE:                    This is a net lease transaction under which all
                              costs and liabilities, including without
                              limitation, for insurance, maintenance and taxes,
                              are paid by Lessee for the term of the lease.
                              Transferable manufacturer's guarantees or
                              warranties will be passed on to Lessee, assuming
                              due performance of Lessee obligations.

ADJUSTMENT OF                 The rental amount quoted in this Proposal will be
RENTAL FACTOR:                adjusted prior to the date of preparation of any
                              Equipment Lease Schedule to reflect changes equal
                              to or greater than one quarter of one percent
                              (.25%) in the weekly average of the Three Year
                              Treasury Note interest rate, as specified in
                              Federal Reserve statistical release H.15 from the
                              five banking days preceding the date of this
                              Proposal to the five banking days preceding the
                              invoice date of the final shipment on the
                              Schedule. Changes to the benchmark rate of less
                              than one quarter of one percent (.25%) will not
                              affect the Lease Rate Factor quoted herein. The
                              Three Year Treasury Note H.15 statistic is updated
                              daily by the U.S. Federal Reserve for the
                              preceding day's yield. The statistic is publicly
                              available on the Internet at
                              http://www.bog.frb.fed.us/releases/h15/.

EQUIPMENT                     Purchase orders for equipment shall be placed by
PROCUREMENT:                  Lessee with Cisco Systems, Inc., or a Cisco Value
                              Added Reseller, with all rights assigned to Lessor
                              upon Lessor's election to fund. All such purchase
                              orders shall he subject to the standard Terms and
                              Conditions of Sale of Cisco Systems, Inc. or such
                              Cisco Value Added Reseller, including the "net 30"
                              payment terms commencing from date of shipment. No
                              funding shall occur prior to execution by the
                              parties of CSC's standard Master Agreement to
                              Lease Equipment ("Master Lease Agreement"). If,
                              for any reason, Lessor does not fund any equipment
                              or lease, or any contemplated lease is otherwise
                              not consummated, Lessee shall be solely
                              responsible for payment in full of the purchase
                              price (together with ancillary costs and expenses)
                              associated with any outstanding orders.
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ECONOMIC                      All purchase orders that are related to the
UTILIZATION DATE:             approved pricing scenarios on this document must
                              be received within 90 days.

PRICING SCENARIO              In accordance with the pricing and configuration
#20067                        in this pricing scenario, the monthly rental
                              payment made in Advance for each Rental Period
Pricing Scenario Accepted:    ("Rent") will be payable on the 1st day of payment
                              period. The Rental Period (Rent") on the lease
------                        would be the total Equipment Cost multiplied by
                              the Lease Rate Factor. Assuming that Soft Costs
Pricing Scenario Declined:    make up less than 10% of the total Equipment Cost.
                              Soft Costs will be included in the Equipment Lease
------                        Rate Factor. If Soft Costs are greater than 10%,
                              CSC will recalculate the rental to reflect the
                              stated Soft Costs Factors.

                              Cisco Equipment: Lease Rate Factor of 2.8900% for
                              36 months

                              Cisco Main/Services: Lease Rate Factor of
                              2.778000% for 36 months

                              Cisco Software: Lease Rate Factor of 3.3900% for
                              36 months

                              Notwithstanding the foregoing, CSC is not
                              responsible for maintenance, software or ancillary
                              services relating to the equipment, nor for
                              ensuring that any necessary maintenance or
                              services agreements or software licenses with
                              Cisco Systems or any other third party are in
                              effect at any time.

Rental Factor:                The rental amount expressed, as a percentage of
                              the total equipment cost (including all costs
                              defined in the pricing scenario) is 2.8900% per
                              the payment frequency defined in the pricing
                              scenarios accepted both the lessee and CSC.

End of Lease Options:         At the end of the Original Term of the Lease,
                              Lessee may select one of the following options:
                              (1) purchase the equipment for the then Fair
                              Market Value (to be defined in the Lease
                              documentation) or (2) subject to the consent of
                              Lessor, renew the lease of the equipment on a
                              month-to-month basis for the daily equivalent of
                              the original Rent, payable monthly in advance, or
                              (3) return the Equipment to the Lessor.

CREDIT APPROVAL:              This Proposal includes only a brief description of
                              the substantive terms and conditions of the
                              contemplated lease transactions and is not
                              intended as a formal commitment of credit by CSC
                              or Cisco Systems. Any funding by CSC for the
                              purchase of equipment is subject to the credit
                              approval of CSC (including the absence of any
                              material adverse change, in the judgment of CSC,
                              in the business or financial condition or
                              prospects of Lessee) and to satisfactory
                              documentation including as described below. You
                              agree to provide two years' audited financial
                              statements, bank

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                              references, a completed credit application and any
                              other required credit information along with the
                              signed copy of this Proposal. You hereby authorize
                              CSC and/or its agents to make a complete credit
                              investigation and to relate this information to
                              others as necessary to secure credit approval.

The parties acknowledge that the financing contemplated by this Proposal is
subject to the above-referenced conditions and the execution and delivery of all
appropriate documents (in form and substance satisfactory to CSC), including
without limitation, to the extent applicable, the Master Lease Agreement, any
Schedule, certificate of acceptance, lease assignment of purchase order, UCC
financing statements, legal opinion and other documents and agreements
reasonably required by CSC. You agree to execute and return to CSC, within 10
days of receipt, the Master Lease Agreement.

This Proposal, if not acknowledged and agreed to by the lessee, will expire 30
days from the date of this document. This Proposal is confidential and may not
be disclosed to any person or entity without our consent.

Thank you for the opportunity to present this Proposal. We look forward to doing
business with you. If you have any questions, please do not hesitate to contact
me.

Sincerely.

CISCO SYSTEMS CAPITAL CORPORATION         ACKNOWLEDGED AND AGREED:

                                          Cmerun Inc.
By: /s/ Susan Wood
    ------------------
    Susan Wood                            By: /s/ Gerald J. McGovern
                                              ----------------------------------
                                              (Authorized  Signature)

                                          Name: Gerald J. McGovern
                                                --------------------------------

                                          Title: CFO
                                                 -------------------------------

                                          Dated: 3/21/00
                                                 -------------------------------

                                          Lessee is willing to accept scheduling
                                          of partial purchase order shipments
                                          [Note. Failure to circle either
                                          option, shall be deemed an instruction
                                          not to schedule partial purchase order
                                          shipments.]