<PAGE>
                                                                    EXHIBIT 10.7
                      COMMERCIAL LEASE AND DEPOSIT RECEIPT


Received from _______________ KARTOFFELSOFT, INC. ___________________
hereinafter referred to as LESSEE, the sum of $__12,376.00--(__Twelve Thousand
Three Hundred Seventy Six & 00/100__________________), evidenced by
______Check___, as a deposit which shall belong to Lessor and shall be applied
as follows

<TABLE>
<CAPTION>
                                                                Total        Received   Due By 1/1/2000
<S>                                                         <C>           <C>           <C>
Rent for the period from __1/1/200 to 12/31/2000-__H,I,M    $_12,376.00   $___________  $____12,376.00_
Security deposit (not applicable toward last month's rent)  $_12,376.00   $___________  $____12,376.00_
Other____________  Common Area Charge____________________   $____247.52   $___________  $_______247.52_
Total____________________________________________________   $_24,999.52   $___________  $____24,999.52_
</TABLE>

     In the event that this Lease is not accepted by the Lessor within __15__
days, the total deposit received shall be refunded.

     Lessee offers to lease from Lessor the premises situated in the City of
Menlo Park, County of San Mateo, State of California, described as __6,188 sq.
ft. portion at 3475-H-I-M___Edison Way of___ a__larger 40,000 Sq. Ft.
Building____________________ upon the following TERMS and CONDITIONS:

1.   TERM: The term hereof shall commence on __January 1, 2000___ and end on
     __December 31, 2000____.
2.   RENT: The total rent plus common area shall be __$151,482.23__payable as
     follows: ___$12,623.52---- on the first day of each month__. All rents
     shall be paid to Lessor or his/her authorized agent, at the following
     address:
     ____ Ronald M. Newdoll, 3475-A Edison Way, Menlo Park, CA 94025 TEL: (415)
     365-2843________ or at such other places as may be designated by Lessor
     from time to time. In the event rent is not paid within __10__ days after
     due date, Lessee agrees to pay a late charge of $125.00 plus interest at 8%
     per annum on the delinquent amount. Lessee further agrees to pay $25.00 for
     each dishonored bank check. The late charge period is not a grace period,
     and Lessor is entitled to make written demand for any rent if not paid when
     due.
3.   USE: The premises are to be used for the operation of ____Software
     Development & Other Related __Activities___________________and for no other
     purpose, without prior written consent of Lessor. Lessee shall not commit
     any waste upon the premises, or any nuisance or act which may disturb the
     quiet enjoyment of any tenant in the building.
4.   USES PROHIBITED: Lessee shall not use any portion of the premises for
     purposes other than those specified. No use shall be made or permitted to
     be made upon the premises, nor acts done, which will increase the existing
     rate of insurance upon the property, or cause cancellation of insurance
     policies covering the property. Lessee shall not conduct or permit any sale
     by auction on the premises.
5.   ASSIGNMENT AND SUBLETTING: Lessee shall not assign this Lease or sublet any
     portion of the premises without prior written consent of the Lessor, which
     shall not be unreasonably withheld. Any such assignment or subletting
     without consent shall be void and, at the option of the Lessor shall
     terminate this Lease.
6.   ORDINANCES AND STATUTES: Lessee shall comply with all statutes, ordinances,
     and requirements of all municipal, state and federal authorities now in
     force, or which may later be in force. The commencement or pendency of any
     state or federal court abatement proceeding affecting the use of the
     premises shall, at the option of the Lessor, be deemed a breach of this
     Lease.
7.   MAINTENANCE, REPAIRS, ALTERATIONS: Unless otherwise indicated, Lessee
     acknowledges that the premises are in a good order and repair. Lessee
     shall, at his/her own expense, maintain the premises in a good and safe
     condition, including plate glass, electrical wiring, plumbing and
     heating installations, and any other system or equipment. The premises
     shall be surrendered, at termination of the Lease, in as good condition
     as received, normal wear and tear excepted. Lessee shall be responsible
     for all repairs required, except the roof, exterior walls, structural
     foundations, and_____________________________________________________
     which shall be maintained by Lessor. No improvement or alteration of the
     premises shall be made without the prior written consent of Lessor.
     Prior to the commencement of any substantial repair, improvement, or
     alteration, Lessee shall give Lessor at least two (2) days written
     notice in order that Lessor may post appropriate notices to avoid any
     liability for liens.
8.   ENTRY AND INSPECTION: Lessee shall permit Lessor or Lessor's agents to
     enter the premises at reasonable times and upon reasonable notice for the
     purpose of inspecting the premises, and shall permit Lessor, at any time
     within sixty (60) days prior to the expiration of this Lease, to place upon
     the premises any usual "To Let" or "For Lease" signs, and permit persons
     desiring to lease the premises to inspect the premises at reasonable times.
9.   INDEMNIFICATION OF LESSOR: Lessor shall not be liable for any damage or
     injury to Lessee, or any other person, or to any property, occurring on the
     premises. Lessee agrees to hold Lessor harmless from any claims for damages
     arising out of Lessee's use of the premises, and to indemnify Lessor for
     any expense incurred by Lessor in defending any such claims.
10.  POSSESSION: If Lessor is unable to deliver possession of the premises at
     the commencement date set forth above, Lessor shall not be liable for any
     damage caused by the delay, nor shall this Lease be void or voidable but
     Lessee shall not be liable for any rent until possession is delivered.
     Lessee may terminate this lease if possession is not delivered within
     __15__days of the commencement term in Item 1.


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11.  LESSEE'S INSURANCE: Lessee, at his/her expense, shall maintain plate glass
     and public liability insurance, including bodily injury and property
     damage, insurance, Lessee and Lessor with minimum coverage as follows: of
     $500,000. Lessee shall provide Lessor with a Certificate of Insurance
     showing Lessor as additional insured. The policy shall require ten (10)
     days' written notice to Lessor prior to cancellation or material change of
     coverage.
12.  LESSOR'S INSURANCE: Lessor shall maintain hazard insurance covering one
     hundred percent (100%) replacement cost of the improvements throughout the
     Lease term. Lessor's insurance will not insure Lessee's personal property
     or leasehold improvements.
13.  SUBROGATION: To the maximum extent permitted by insurance policies which
     may be owned by the parties, Lessor and Lessee waive any and all rights of
     subrogation which might otherwise exist.
14.  UTILITIES: Lessee agrees that he/she shall be responsible for the payment
     of all utilities including gas, electricity and other services delivered to
     the premises.
15.  SIGNS: Lessor reserves the exclusive right to the roof, side and rear walls
     of the premises. Lessee shall not construct any projecting sign or awning
     without the prior written consent of Lessor, which shall not be
     unreasonably withheld.
16.  ABANDONMENT OF PREMISES: Lessee shall not vacate or abandon the premises at
     any time during the term of this Lease. If Lessee does abandon or vacate
     the premises, or is dispossessed by process of law, or otherwise, any
     personal property belonging to Lessee left on the premises shall be deemed
     to be abandoned, at the option of the Lessor.
17.  TRADE FIXTURES: Any and all improvements made to the premises during the
     term shall belong to the Lessor, except trade fixtures of the Lessee.
     Lessee may, upon termination, remove all his/her trade fixtures, but shall
     pay for all costs necessary to repair any damage to the premises occasioned
     by the removal.
18.  DESTRUCTION OF PREMISES: In the event of a partial destruction of the
     premises during the term, from any cause, Lessor shall promptly repair the
     premises, provided that such repairs can be reasonably made within sixty
     (60) days. Such partial destruction shall not terminate this Lease, except
     that Lessee shall be entitled to a proportionate reduction of rent while
     such repairs are being made, based upon the extent to which the making of
     such repairs interferes with the business of Lessee on the premises. If the
     repairs cannot be made within sixty (60) days, this Lease may be terminated
     at the option of either party by giving written notice to the other party
     within the sixty (60) day period.
19.  HAZARDOUS MATERIALS: Lessee shall not use, store, or dispose of any
     hazardous substances upon the premises, except the use and storage of such
     substances that are customarily used in Lessee's business, and are in
     compliance with all environmental laws. Hazardous substances means any
     hazardous waste, substance or toxic materials regulated under any
     environmental laws or regulations applicable to the property.
20.  INSOLVENCY: The appointment of a receiver, an assignment for the benefits
     of creditors, or the filing of a petition in bankruptcy by or against
     Lessee, shall constitute a breach of this Lease by Lessee.
21.  DEFAULT: In the event of any breach of this Lease by Lessee, Lessor may,
     at his/her option, terminate the Lease and recover from Lessee: (a) the
     worth at the time of award of the unpaid rent, which had been earned at
     the time of termination; (b) the worth at the time of award of the
     amount by which the unpaid rent which would have been earned after
     termination until the time of the award exceeds the amount of such
     rental loss that the Lessee proves could have been reasonably avoided;
     (c) the worth at the time of award of the amount by which the unpaid
     rent for the balance of the term after the time of award exceeds the
     amount of such rental loss that the Lessee proves could be reasonably
     avoided; and (d) any other amount necessary to compensate Lessor for all
     the detriment proximately caused by the Lessee's failure to perform
     his/her obligations under the Lease or which in the ordinary course of
     things would be likely to result therefrom.
          Lessor may, in the alternative, continue this lease in effect, as long
     as Lessor does not terminate Lessee's right to possession, and Lessor may
     enforce all of Lessor's rights and remedies under the Lease, including the
     right to recover the rent as it becomes due under the Lease. If said breach
     of Lease continues, Lessor may, at any time thereafter, elect to terminate
     the Lease.
          Nothing contained herein shall be deemed to limit any other rights or
     remedies which Lessor may have.
22.  SECURITY: The security deposit set forth above shall secure the performance
     of the Lessee's obligations. Lessor may, but shall not be obligated to
     apply all or portions of the deposit on account of Lessee's obligations.
     Any balance remaining upon termination shall be returned to Lessee. Lessee
     shall not have the right to apply the security deposit in payment of the
     last month's rent.
23.  DEPOSIT REFUNDS: The balance of all deposit shall be refunded within three
     weeks (or otherwise required by law), from date possession is delivered to
     Lessor of his/her authorized Agent, together with a statement showing any
     charges made against such deposits by Lessor.
24.  ATTORNEY'S FEE AND COSTS: In any action or proceeding involving a dispute
     between Lessor and Lessee arising out of this Lease, the prevailing party
     shall be entitled to reasonable attorney's fees.
25.  WAIVER: No failure of Lessor to enforce any term of this Lease shall be
     deemed to be a waiver.


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26.  NOTICES: Any notice which either party may or is required to give, shall be
     given by mailing the same, postage prepaid, to Lessee at the premises, or
     to Lessor at the address shown in item 2, or at such other places as may be
     designated by the parties from time to time. Notice shall be effective five
     days after mailing, or on personal delivery.
27.  HOLDING OVER: Any holding over after the expiration of this Lease, with the
     consent of Owner, shall become a month-to-month tenancy at a monthly rent
     of $12,113.10 _payable in advance and otherwise subject to the terms of
     this Lease, as applicable, until either party shall terminate the same by
     giving the other party thirty (30) days written notice.
28.  TIME: Time is of the essence of this Lease.
29.  HEIRS, ASSIGNS, SUCCESSORS: This lease is binding upon and inures to the
     benefit of the heirs, assigns and successors of the parties.
30.  OPTION TO RENEW: Provided that Lessee is not in default in the performance
     of this Lease, Lessee shall have the option to renew the Lease for an
     additional term of ___________________ commencing at the expiration of the
     initial Lease term. All of the terms and conditions of the Lease shall
     apply during the renewal term, except that the monthly rent shall be the
     sum of __$_____________.
     The option shall be exercised by written notice given to Lessor not less
     than __60__ days prior to the expiration of the initial Lease term. If
     notice is not given within the time specified, this Option shall expire.
31.  AMERICANS WITH DISABILITIES ACT: The parties are alerted to the existence
     of the Americans With Disabilities Act, which may require costly structural
     modifications. The parties are advised to consult with a professional
     familiar with the requirements of the Act.
32.  LESSOR'S LIABILITY: In the event of a transfer of Lessor's title or
     interest to the property during the term of this Lease, Lessee agrees that
     the grantee of such title or interest shall be substituted as the Lessor
     under this Lease, and the original Lessor shall be released of all further
     liability; provided that all deposits shall be transferred to the grantee.
33.  ESTOPPEL CERTIFICATE:
     (a)  On ten (10) days prior written notice from Lessor, Lessee shall
          execute, acknowledge, and deliver to Lessor a statement in writing:
          (1) certifying that this Lease is unmodified and in full force and
          effect (or, if modified, stating the nature of such modification and
          certifying that this Lease, as so modified, is in full force and
          effect), the amount of any security deposit, and the date to which the
          rent and other charges are paid in advance, if any; and (2)
          acknowledging that there are not, to Lessee's knowledge, any uncured
          defaults on the part of the Lessor, or specifying such defaults if any
          are claimed. Any such statement may be conclusively relied upon by any
          prospective buyer or encumbrancer of the premises.
     (b)  At Lessor's option, Lessee's failure to deliver such statement within
          such time shall be a material breach of this Lease or shall be
          conclusive upon Lessee: (1) that this Lease is in full force and
          effect, without modification except as may be represented by Lessor:
          (2) that there are no uncured defaults in Lessor's performance; and
          (3) that not more than one month's rent has been paid in advance.
     (c)  If Lessor desires to finance, refinance, or sell the premises, or any
          part thereof, Lessee agrees to deliver to any lender or buyer
          designated by lessor such financial statements of Lessee as may be
          reasonably required by such lender or buyer. All financial statements
          shall be received by the Lessor or the lender or buyer in confidence
          and shall be used only for the purposes set forth.
34.  ENTIRE AGREEMENT: The foregoing constitutes the entire Agreement between
     the parties and may be modified only in writing signed by all parties. The
     following exhibits are a part of this lease: Exhibit A: _Lessee agrees to
     limit total personnel occupying space to no more than 15 people____________
     Exhibit B: ATTACHMENT A____________________________________________________


The undersigned Lessee hereby acknowledges that he/she has thoroughly read and
approved each of the provisions contained in this Offer, and agrees to the terms
and conditions specified. Lessee acknowledges receipt of a copy of the accepted
agreements.

Lessee: /S/ ANDREW CHMYZ   Date: 12/15/99   Lessee:_______________  Date:_______
        -----------------
        Andrew Chmyz,
        Controller
        (650) 549-3124


                                   ACCEPTANCE

The undersigned Lessor accepts the foregoing Offer and agrees to lease the
premises on the terms and conditions set forth above.

Lessor:_________________  Date:________  Lessor:_______________  Date:__________
       Ronald M. Newdoll



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