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                                                                   EXHIBIT 10.43

                    [CORNISH & CAREY COMMERCIAL LETTERHEAD]


                                    SUBLEASE


 Sublessor: MOAI TECHNOLOGIES, INC. Premises: 800 CALIFORNIA STREET, SUITE 200
                                              MOUNTAIN VIEW, CALIFORNIA

 Sublessee: CIDCO, INC.             Date:     AUGUST 16, 2000

1.      Parties:

        This Sublease is made and entered into as of August 16, 2000, by and
        between Moai Technologies, Inc. (Sublessor), and Cidco, Inc.
        (Sublessee), under the Master Lease dated December 17, 1999, between 800
        California, LLC, as (Lessor) and Sublessor under this Sublease as
        (Lessee). A copy of the Master Lease is attached hereto as Exhibit "A"
        and incorporated herein by this reference.

2.      Provisions Constituting Sublease:

2.1            This Sublease is subject to all of the terms and conditions of
               the Master Lease. Sublessee hereby assumes and agrees to perform
               all of the obligations of Lessee under the Master Lease to the
               extent said obligations apply to the Subleased Premises and
               Sublessee's use of the common areas, except as specifically set
               forth herein. Sublessor hereby agrees to cause Lessor, under the
               Master Lease, to perform all of the obligations of Lessor
               thereunder to the extent said obligations apply to the Subleased
               Premises and Sublessee's use of the common areas. Sublessee shall
               not commit or permit to be committed on the Subleased Premises or
               on any other portion of the Project any act or omission which
               violates any term or condition of the Master Lease. Except to the
               extent waived or consented to in writing by the other party or
               parties hereto who are affected thereby, neither of the parties
               hereto will, by renegotiations of the Master Lease, assignment,
               subletting, default or any other voluntary action, avoid or seek
               to avoid the observance or performance of the terms to be
               observed or performed hereunder by such party but, will at all
               times, in good faith assist in carrying out all the terms of this
               Sublease and in taking all such action as may be necessary or
               appropriate to protect the rights of the other party or parties
               hereto who are affected thereby against impairment. Nothing
               contained in this Section 2.1 or elsewhere in this Sublease shall
               prevent or prohibit Sublessor (a) from exercising its right to
               terminate the Master Lease pursuant to the terms thereof or (b)
               form assigning its interest in this Sublease or subletting the
               Premises to any other third party.

2.2            All of the terms and conditions contained in the Master Lease are
               incorporated herein, except as specifically provided below, and
               shall together with the terms and conditions specifically set
               forth in this Sublease constitute the complete terms and
               conditions of this Sublease. The following paragraphs of the
               Master Lease shall not be included in this Sublease:

                   1.5, 1.6, 1.7, 1.8, 1.9, 3, 4.1, 5, 15 Supplemental Terms

                   Paragraph #'s 2, 3, 4, 8, 9, 13, 17


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3.      Premises:

        Sublessor leases to Sublessee and Sublessee leases from Sublessor the
        Subleased Premises upon all of the terms, covenants and conditions
        contained in this Sublease. The Subleased Premises consist of
        approximately 6,095+/- square feet, located at 800 California Street,
        Mountain View as shown and described in Exhibit "B".

4.      Rent:

        Upon execution of this Agreement, Sublessee shall pay to Sublessor as
        Rent for the Subleased Premises the sum of Forty Five Thousand and Seven
        Hundred Twelve and 50/100 Dollars ($45,712.50), representing the first
        month's rent. Thereafter, rent shall be in accordance with the following
        schedule:


<TABLE>
<CAPTION>
                   MONTHS          AMOUNT PER SQUARE FOOT/FULL SERVICE
                   ------          -----------------------------------
<S>                                <C>
                   01-12                          $7.50
                   13-24                          $7.80
                   25-36                          $8.11
                   37-48                          $8.40
                   48-55                          $8.77
</TABLE>


        The rental amount shall be paid, without deductions, offset, prior
        notice or demand. If the commencement date or the termination date of
        the Sublease occurs on a date other than the first day or the last day,
        respectively, of a calendar month, then the Rent for such partial month
        shall be prorated and the prorated Rent shall be payable on the Sublease
        commencement date or on the first day of the calendar month in which the
        Sublease termination date occurs, respectively.

5.      Security Deposit:

               Upon execution of this Agreement, Sublessee shall pay to
Sublessor an equivalent of six month's rent ($274,275.00) as security deposit.
Provided that Sublessee has not been in default and Sublessor exercises its
option to terminate this Sublease, as described in Paragraph 14 Sublessor agrees
to apply 1/6 of the Security Deposit to months 21-24th of the Sublease. The
balance of the Security Deposit shall be retained throughout the Sublease term.

               If Sublessor does not exercise its option to terminate the
Sublease and Sublessee is not in default and is at a $200 million market cap,
then Sublessor shall apply 1/6th of the Security Deposit to the next two (2)
month's rent due. Sublessee shall be responsible for providing written
notification to Sublessor that the $200 million market cap has been met.

               In the event Sublessee has performed all of the terms and
conditions of this Sublease during the term hereof, Sublessor shall return to
Sublessee, within ten (10) days after Sublessee has vacated the Subleased
Premises, the remaining Security Deposit less any sums due and owing to
Sublessor.

6.      RIGHTS OF ACCESS AND USE:

        6.1 Use:

                Sublessee shall use the Subleased Premises only for those
        proposes permitted in the Master Lease, unless Sublessor and Master
        Lessor consent in writing to other uses prior to the commencement
        thereof.

7.      SUBLEASE TERM:

        7.1 Sublease Term:

                The Sublease Term shall be for the period commencing on
        September 15, 2000, and terminate March 31, 2005 (see paragraph #15).


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        7.2 Inability to Deliver Possession:

                In the event Sublessor is unable to deliver possession of the
        Subleased Premises at the commencement of the term, Sublessor shall not
        be liable for any damage caused thereby nor shall this Sublease be void
        or voidable, but Sublessee shall not be liable for Rent until such time
        as Sublessor offers to deliver possession of the Subleased Premises to
        Sublessee, but the term hereof shall not be extended by such delay. If
        Sublessee, with Sublessor's consent, takes possession prior to
        commencement of the term, Sublessee shall do so subject to all the
        covenants and conditions hereof and shall pay Rent for the period ending
        with commencement of the term at the same rental as that prescribed for
        the first month of the term prorated at the rate of 1/30th thereof per
        day. In the event Sublessor has been unable to deliver possession of the
        Sublease Premises within thirty (30) days from the commencement date,
        Sublessee, at Sublessee's option, may terminate this Sublease.

8.      NOTICES:

                All notices, demands, consents and approvals which may or are
        required to be given by either party to the other hereunder shall be
        given in the manner provided in the Master Lease at the addresses shown
        below. Sublessor shall notify Sublessee of any Event of Default under
        the Master Lease, or of any other event of which Sublessor has actual
        knowledge which will impair Sublessee's ability to conduct its normal
        business at the Subleased Premises, as soon as reasonable practicable
        following Sublessor's receipt of notice from the Lessor of an Event of
        Default or actual knowledge of such impairment. If Sublessor elects to
        terminate the Master Lease, Sublessor shall so notify Sublessee by
        giving at least thirty (30) days notice prior to the effective date of
        such termination.

         SUBLESSOR'S      Moai Technologies     SUBLESSEE'S          Cidco, Inc.
            ADDRESS:         25 Lusk Street        ADDRESS:  220 Cochrane Circle
                    San Francisco, CA 94107                      Morgan Hill, CA
               Attn:        Teresa Stancato                                95037
                                                      Attn:       Rick Kent, CFO

       PHONE NUMBER:         (415) 625-2523   PHONE NUMBER:         408-776-2532
         FAX NUMBER:         (415) 625-1202     FAX NUMBER:

9.      BROKER FEE:

        Upon execution of the Sublease, Sublessor shall pay Cornish & Carey
Commercial, a licensed real estate broker, fees set forth in a separate
agreement between Sublessor and Broker.

10.     BROKER REPRESENTATION:

        The only Brokers involved in this Sublease are Cornish & Carey
Commercial representing Sublessee and Sublessor. Both Sublessor and Sublessee
consent to such dual representation and waive any conflict of interest arising
out of such dual agency.

11.     COMPLIANCE WITH AMERICANS WITH DISABILITIES ACT:

        Sublessor shall be responsible for the installation and cost of any and
all improvements, alterations or other work required on or to the Subleased
Premises or to any other portion of the property and/or building of which the
Subleased Premises are a part, required or reasonably necessary because of: (1)
Sublessee's use of the Subleased Premises or any portion thereof; (2) the use by
a Sublessee by reason of assignment or sublease; or (3) both, including any
improvements, alterations or other work required under the Americans With
Disabilities Act of 1990.


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Compliance with the provisions of this Section 8 shall be a condition of
Sublessor granting its consent to any assignment or Sublease of all or portion
of this Sublease and the Subleased Premises described in this Sublease.

12.     COMPLIANCE WITH NONDISCRIMINATION REGULATIONS:

        It is understood that it is illegal for Sublessor to refuse to display
or sublease the Subleased Premises or to assign, surrender or sell the Master
Lease, to any person because of race, color, religion, national origin, sex,
sexual orientation, marital status or disability.

13.     TOXIC CONTAMINATION DISCLOSURE:

        Sublessor and Sublessee each acknowledge that they have been advised
that numerous federal, state, and/or local laws, ordinances and regulations
(Laws) affect the existence and removal, storage, disposal, leakage of and
contamination by materials designated as hazardous or toxic (Toxics). Many
materials, some utilized in everyday business activities and property
maintenance, are designated as hazardous or toxic.

        Some of the Laws require that Toxics be removed or cleaned up by
landowners, future landowners or former landowners without regard to whether the
party required to pay for "clean up" caused the contamination, owned the
property at the time the contamination occurred or even knew about the
contamination. Some items, such as asbestos or PCBs, which were legal when
installed, now are classified as Toxics and are subject to removal requirements.
Civil lawsuits for damages resulting from Toxics may be filed by third parties
in certain circumstances.

        Sublessor and Sublessee each acknowledge that Broker has no specific
expertise with respect to environmental assessment or physical condition of the
Subleased Premises, including, but not limited to, matters relating to: (i)
problems which may be posed by the presence or disposal of hazardous or toxic
substances on or from the Subleased Premises, (ii) problems which may be posed
by the Subleased Premises being within the Special Studies Zone as designated
under the Alquist-Priolo Special Studies Zone Act (Earthquake Zones), Section
2621 - 2630, inclusive of California Public Resources Code, and (iii) problems
which may be posed by the Subleased Premises being within a HUD Flood Zone as
set forth in the U.S. Department of Housing and Urban Development "Special Flood
Zone Area Maps", as applicable.

        Sublessor and Sublessee each acknowledge that Broker has not made an
independent investigation or determination of the physical or environmental
condition of the Subleased Premises, including, but not limited to, the
existence or nonexistence of any underground tanks, sumps, piping, toxic or
hazardous substances on the Subleased Premises. Sublessee agrees that it will
rely solely upon its own investigation and/or the investigation of professionals
retained by it or Sublessor, and neither Sublessor nor Sublessee shall rely upon
Broker to determine the physical and environmental condition of the Subleased
Premises or to determine whether, to what extent or in what manner, such
condition must be disclosed to potential sublessees, assignees, purchasers or
other interested parties.

14.     RENT ABATEMENT AND DAMAGES TO PERSONAL PROPERTY:

        In the event Sublessor, pursuant to the terms of the Master Lease, is
entitled to and receives rent abatement, then to the extent such rent abatement
affects the Subleased Premises, Sublessee shall be entitled to rent abatement in
an amount that the net rentable area of the Subleased premises bears to the
total net rentable area of the Master Lease, and only to the extent any such
abatement applies to the Sublease Term. In addition, any amounts paid or
credited to Sublessor under the terms of the Master Lease for damage to personal
property shall be credited to Sublessee, subject to the same limitations set
forth above.


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15.     EARLY TERMINATION:

        Sublessor shall have a one time right to terminate this Sublease with
six (6) months prior notice. Notice to be given at the end of the eighteenth
(18th) month of the Sublease term with the actual termination date to be at the
end of the twenty fourth (24th) month. Sublessor shall also have the right to
terminate this Sublease at any time throughout Sublease term upon notification
of Sublessee's intention to Sublease more than 50% of space.

16.     OTHER:

        Each of Sublessee and Sublessor, jointly and severally, shall indemnify,
defend and hold Lessor harmless from and against any and all claims arising out
of:

    (1)  Sublessee's use of the Premises or any part thereof or

    (2)  Any breach or default in the performance of any obligation on
         Sublessee's part to be performed under the terms of the Sublease
         or

    (3)  Any claim for the Sublease Security Deposit and brokerage
         commissions or

    (4)  For any charges or expenses in connection with the Sublease and
         any costs and expenses arising in connection with any such
         claims defined herein.

        SUBLESSOR:    MOAI TECHNOLOGIES, INC.

        By:
                                                -------------------------------
                                                  Date:
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        SUBLESSEE:   Cidco, INC.

                                                -------------------------------
                                                  Date:
                                                        -----------------------


        NOTICE TO SUBLESSOR AND SUBLESSEE: CORNISH & CAREY COMMERCIAL, IS NOT
AUTHORIZED TO GIVE LEGAL OR TAX ADVICE; NOTHING CONTAINED IN THIS SUBLEASE OR
ANY DISCUSSIONS BETWEEN CORNISH & CAREY COMMERCIAL AND SUBLESSOR AND SUBLESSEE
SHALL BE DEEMED TO BE A REPRESENTATION OR RECOMMENDATION BY CORNISH & CAREY
COMMERCIAL, OR ITS AGENTS OR EMPLOYEES AS TO THE LEGAL EFFECT OR TAX
CONSEQUENCES OF THIS DOCUMENT OR ANY TRANSACTION RELATING THERETO. ALL PARTIES
ARE ENCOURAGED TO CONSULT WITH THEIR INDEPENDENT FINANCIAL CONSULTANTS AND/OR
ATTORNEYS REGARDING THE TRANSACTION CONTEMPLATED BY THIS PROPOSAL.


        Exhibit "A" Master Lease
        Exhibit "B" Premises



        LESSOR CONSENT:

        The undersigned, Lessor under the Master Lease attached as Exhibit A,
hereby consents to the subletting of the Subleased Premises described herein on
the terms and conditions contained in this Sublease. This Consent shall apply
only to this Sublease and shall not be deemed to be a consent to any other
Sublease.

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        LESSOR: ________________________

        By:
                                                -------------------------------
                                                  Date:
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