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                                                                   EXHIBIT 10.46

[RENAULT & HANDLEY LETTERHEAD]

THIS LEASE, executed in duplicate at Palo Alto, California, this 25th day of
September 1998,

PARTIES

by and between

Y.A. Tittle and Renault & Handley Employees Investment Co.

and

CIDCO Incorporated, a Delaware corporation

hereinafter called respectively Lessor and Lessee, without regard to number or
gender.

PREMISES

        1. WITNESSETH: That Lessor hereby leases to Lessee, and Lessee hires
from Lessor, those certain premises, hereinafter in this lease designated as
"the Premises", with the appurtenances, situated in the City of Morgan Hill,
County of Santa Clara, State of California, and more particularly described as
follows, to-wit:

An approximately 46,380 square foot building and approximate 3.11 acre lot
commonly known and numbered as 220 Cochrane Circle, APN 726-34-10.

USE

        2. The Premises shall be used and occupied by Lessee for office, R&D and
warehousing and for no other purpose without the prior written consent of
Lessor.

TERM

        3. The term shall be for seven (7) years, commencing upon the close of
escrow for the Premises under the Purchase and Sale Agreement dated September
25, 1998 between Lessor and Lessee as Buyer and Seller, respectively. Upon close
of escrow, Lessor and Lessee shall execute a Memorandum of Lease Commencement,
fixing the actual commencement and termination dates of this Lease.

RENTAL

        4. Rent shall be payable to the Lessor without deduction or offset at
such place or places as may be designated from time to time by the Lessor as
follows:

        A.      FORTY THOUSAND THREE HUNDRED FIFTY AND 60/100THS DOLLARS
                ($40,350.60) WILL BE DUE UPON EXECUTION OF THIS LEASE
                CONSTITUTING THE FIRST MONTHS'S RENT. SAID AMOUNT SHALL BE
                DEPOSITED INTO ESCROW AT FIRST AMERICAN TITLE COMPANY, 431
                FLORENCE STREET, SUITE 100, PALO ALTO, CALIFORNIA, ESCROW NO.
                113127 AND PAYABLE TO LESSOR UPON CLOSE OF SAID ESCROW.
                $40,350.60 WILL BE DUE AND PAYABLE DIRECTLY TO LESSOR ON THE 1ST
                DAY OF EACH SUCCEEDING MONTHS THROUGH THE INITIAL TERM, SUBJECT
                TO THE ADJUSTMENTS AS SET FORTH IN PARAGRAPH 4.B. BELOW. ANY
                RENT DUE FOR A PARTIAL MONTH SHALL BE PRORATED BASED ON A THIRTY
                DAY MONTH.

        B.      ADJUSTMENT OF RENT. THE MONTHLY RENT (PARAGRAPH 4.A. ABOVE)
                PAYABLE DURING THE SECOND AND EACH SUCCEEDING YEAR OF THE LEASE
                TERM (AS MAY BE EXTENDED BY OPTION OR OTHERWISE) SHALL BE
                SUBJECT TO INCREASES AS FOLLOWS: "THE REVISED SAN
                FRANCISCO-OAKLAND-SAN JOSE CONSUMER PRICE INDEX -- "ALL URBAN
                CONSUMERS", "ALL ITEMS" (1982-1984 = 100) PUBLISHED BY THE U.S.
                DEPARTMENT OF LABOR, BUREAU OF LABOR STATISTICS (THE "INDEX")
                FOR THE MONTH AVAILABLE MOST IMMEDIATELY PRECEDING THE
                COMMENCEMENT DATE OF THIS LEASE WILL BE THE "BEGINNING INDEX".
                ON EACH ANNIVERSARY OF THE COMMENCEMENT DATE, IF THE THEN
                PUBLISHED INDEX FOR THE SAME MONTH (THE EXTENSION INDEX) HAS
                INCREASED OVER THE BEGINNING INDEX, THE MONTHLY RENT FOR THE
                ENSUING YEAR OF THE LEASE SHALL BE ADJUSTED BY MULTIPLYING THE
                MONTHLY RENT IN PARAGRAPH 4.A. BY A FRACTION, THE NUMERATOR OF
                WHICH IS THE EXTENSION INDEX AND THE DENOMINATOR OF WHICH IS THE
                BEGINNING INDEX. IF DURING THE TERM OF THIS LEASE OR ANY
                EXTENSION THEREOF, THE BUREAU OF LABOR STATISTICS CHANGES OR
                MODIFIES THE INDEX, THE PARTIES HERETO AGREE THAT THE "NEW"
                INDEX SHALL BE IMMEDIATELY ADOPTED FOR PURPOSES OF CALCULATING
                FUTURE RENTAL ADJUSTMENTS.

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SECURITY DEPOSIT

        5. Lessee has deposited with Lessor $45,000.00* as security for the full
and maximum performance of each and every term, provision, covenant and
condition of this Lease. In the event Lessee defaults in respect of any of the
terms, provisions, covenants or conditions of this Lease, including but not
limited to the payment of rent, Lessor may use, apply or retain the whole or any
part of such security for the payment of any rent in default or for any other
sum which Lessor may spend or be required to spend by reason of Lessee's
default. Should Lessee faithfully and fully comply with all of the terms,
provisions, covenants and conditions of this Lease, the security of any balance
thereof shall be returned to Lessee or, at the option of Lessor, to the last
assignee of Lessee's interest in this Lease at the expiration of the term
hereof. Lessee shall not be entitled to any interest on said security deposit.

* INTO ESCROW AT FIRST AMERICAN TITLE COMPANY, 431 FLORENCE STREET, PALO ALTO,
  CALIFORNIA, ESCROW NO. 113127, PAYABLE TO LESSOR UPON CLOSE OF ESCROW.

POSSESSION

ACCEPTANCE OF PREMISES AND CONSENT TO SURRENDER

        7. By entry hereunder, the Lessee accepts the Premises as being in good
and satisfactory condition. The Lessee agrees on the last day of the term
hereof, or on sooner termination of this Lease, to surrender the premises,
together with all alterations, additions, and improvements which may have been
made in, to, or on the Premises by Lessor or Lessee, unto Lessor in the same
good condition as at Lessee's entry into the Premises excepting for such wear
and tear as would be normal for the period of the Lessee's occupancy. The
Lessee, on or before the end of the term or sooner termination of this Lease,
shall remove all Lessee's personal property and trade fixtures from the
premises and all property not so removed shall be deemed to be abandoned by the
Lessee. If the Premises be not surrendered at the end of the term or sooner
termination of this Lease, the Lessee shall indemnify the Lessor against loss
or liability resulting from delay by the Lessee in so surrendering the Premises
including, without limitation, any claims made by any succeeding tenant founded
on such delay.

USES PROHIBITED

        8. Lessee shall not commit, or suffer to be committed, any waste upon
the Premises, or any nuisance, or other act or thing which may disturb the
quiet enjoyment of any other tenant in or around the buildings in which the
Premises may be located, or allow any sale by auction upon the Premises, or
allow the Premises to be used for any improper, immoral, unlawful or
objectionable purpose, or place any loads upon the floor, walls, or roof which
endanger the structure, or place any harmful liquids in the drainage system of
the building. No waste materials or refuse shall be dumped upon or permitted to
remain upon any part of the Premises outside of the building proper. No
materials, supplies, equipment, finished products or semi-finished products,
raw materials or articles of any nature shall be stored upon or permitted to
remain on any portion of the Premises outside of the buildings proper.

ALTERATIONS AND ADDITIONS

        9. The lessee shall make no alterations, additions or improvements to
the Premises or any part thereof without first obtaining the prior written
consent of the Lessor. The Lessor may impose as a condition to the aforesaid
consent such requirements as Lessor may deem necessary in Lessor's sole
discretion, including without limitation thereto, the manner in which the work
is done, a right of approval of the contractor by whom the work is to be
performed, the times during which it is to be accomplished, and the requirement
that upon written request of Lessor prior to the expiration or earlier
termination of the Lease, Lessee will remove any or all improvements or
additions to the Premises installed at Lessee's expense. All such alterations,
additions or improvements not specified to be removed shall at the expiration
of earlier termination of the Lease become the property of the Lessor and
remain upon and be surrendered with the Premises. All movable furniture,
business and trade fixtures, and machinery and equipment shall remain the
property of the Lessee and may be removed by the Lessee at any time during the
Lease term when Lessee is not in default hereunder. Items which are not to be
deemed as movable furniture, business and trade fixtures, or machinery and
equipment shall include heating, lighting, electrical systems, air
conditioning, partitioning, carpeting, or any other installation which has
become an integral part of the Premises. The Lessee will at all times permit
notices of non-responsibility to be posted and to remain posted until the
completion of alterations or additions which have been approved by the Lessor.

MAINTENANCE OF PREMISES

        10. Lessee shall, at Lessee's sole cost, keep and maintain the Premises
and appurtenances and every part thereof, including but not limited to,
glazing, sidewalks, parking areas, plumbing, electrical systems, heating and
air conditioning installations, any store front, roof covering -- unless it is
not feasible to repair the existing roof covering and a new roof covering is
required, and the interior of the Premises in good order, condition, and
repair. Lessor at Lessor's sole cost and expense shall maintain the exterior of
the walls, and structural portions of the roof, foundations, walls, and floors
except for any repairs caused by the wrongful act of the Lessee and Lessee's
agents. The Lessor will replace the roof covering if repairs to said covering
are not longer economically feasible in the judgment of roofing experts, and
provided that said replacement is not made necessary by acts of the Lessee and
Lessee's agents. The Lessee shall water, maintain and replace, when necessary,
any shrubbery and landscaping provided by the Lessor on the Premises. The
Lessee expressly waives the benefits of any statute now or hereafter in effect
which would otherwise afford the Lessee the right to make repairs at Lessor's
expense or to terminate this lease because of Lessor's failure to keep the
Premises in good order, conditions or repair.

FIRE AND EXTENDED COVERAGE INSURANCE AND SUBROGATION

                     SEE REVISED INSURANCE CLAUSE ATTACHED

                                     2 OF ?

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                            REVISED INSURANCE CLAUSE

THIS LEASE CLAUSE REPLACES THE INSURANCE CLAUSE (11.) IN THE RENAULT & HANDLEY
NET LEASE FORM.

     11.  LESSEE SHALL NOT USE, OR PERMIT THE PREMISES, OR ANY PART THEREOF, TO
BE USED, FOR ANY PURPOSES OTHER THAN THAT FOR WHICH THE PREMISES ARE HEREBY
LEASED AND NO USE SHALL BE MADE OR PERMITTED TO BE MADE ON THE PREMISES, NOR
ACTS DONE, WHICH WILL CAUSE A CANCELLATION OF ANY INSURANCE POLICY COVERING
SAID BUILDING, OR ANY PART THEREOF, NOR SHALL LESSEE SELL OR PERMIT TO BE KEPT,
USED OR SOLD, IN OR ABOUT THE PREMISES, ANY ARTICLE WHICH MAY BE PROHIBITED BY
THE STANDARD FORM OF FIRE INSURANCE POLICIES. LESSEE SHALL, AT ITS SOLE COST AND
EXPENSE, COMPLY WITH ANY AND ALL REQUIREMENTS, PERTAINING TO THE PREMISES, OF
ANY INSURANCE ORGANIZATION OR COMPANY, NECESSARY FOR THE MAINTENANCE OF
REASONABLE FIRE AND PUBLIC LIABILITY INSURANCE, COVERING SAID BUILDING AND
APPURTENANCES.

     11.1 LESSEE SHALL, AT ITS EXPENSE, OBTAIN AND KEEP IN FORCE DURING THE
TERM OF THIS LEASE A POLICY OF COMMERCIAL GENERAL LIABILITY INSURANCE INSURING
LESSEE, LESSOR, AND ANY THIRD PARTIES NAMED BY LESSOR WHICH MAY INCLUDE
LESSOR'S LENDER, AGAINST ANY LIABILITY ARISING OUT OF THE CONDITION, USE,
OCCUPANCY OR MAINTENANCE OF THE PREMISES. SUCH INSURANCE POLICY SHALL HAVE A
COMBINED SINGLE LIMIT FOR BOTH BODILY INJURY AND PROPERTY DAMAGE IN AN AMOUNT
NOT LESS THAN TWO MILLION AND NO/100THS DOLLARS ($2,000,000.00), WHICH
AGGREGATE AMOUNT SHALL BE SPECIFIC TO THE PREMISES. THE LIMITS OF SAID
INSURANCE SHALL NOT LIMIT THE LIABILITY OF LESSEE HEREUNDER.

     11.2 LESSEE SHALL AT ITS EXPENSE, KEEP IN FORCE DURING THE TERM OF THIS
LEASE, A POLICY OF FIRE AND PROPERTY DAMAGE INSURANCE IN A "SPECIAL" FORM WITH
A SPRINKLER LEAKAGE ENDORSEMENT, INSURING LESSEE'S INVENTORY, FIXTURES,
EQUIPMENT AND PERSONAL PROPERTY WITHIN THE PREMISES FOR THE FULL REPLACEMENT
VALUE THEREOF. WITHIN TEN (10) DAYS OF THE LEASE COMMENCEMENT DATE AND ANNUALLY
THEREAFTER UPON RENEWAL OF SUCH POLICIES, LESSEE SHALL PROVIDE LESSOR WITH
CERTIFICATES OF INSURANCE EVIDENCING COVERAGES THE LESSEE IS REQUIRED TO CARRY
PURSUANT TO 11.1 AND 11.2. THE POLICIES SHALL PROVIDE FOR THIRTY (30) DAYS
ADVANCE WRITTEN NOTICE OF CANCELLATION TO LESSOR AND LESSOR'S LENDER.

     11.3 LESSOR SHALL MAINTAIN A POLICY OF COMMERCIAL GENERAL LIABILITY
INSURANCE AND A POLICY OR POLICIES OF FIRE AND PROPERTY DAMAGE INSURANCE IN A
"SPECIAL" FORM, WITH SPRINKLER LEAKAGE AND, AT THE OPTION OF THE LESSOR,
EARTHQUAKE ENDORSEMENTS, COVERING LOSS OR DAMAGE TO THE BUILDING, INCLUDING
LESSEE'S LEASEHOLD IMPROVEMENTS INSTALLED WITH THE WRITTEN CONSENT OF THE
LESSOR, IN SUCH AMOUNTS AND WITH SUCH COVERAGE AS LESSOR DEEMS ADVISABLE.

     11.4 LESSEE SHALL PAY TO LESSOR AS ADDITIONAL RENT, DURING THE TERM
HEREOF, UPON RECEIPT OF AN INVOICE THEREFORE, ONE HUNDRED PERCENT (100%) OF THE
PREMIUMS AND DEDUCTIBLES (PROVIDED, THE DEDUCTIBLE AMOUNT SHALL BE AMORTIZED
OVER THE USEFUL LIFE OF THE IMPROVEMENT FOR WHICH SUCH INSURANCE DEDUCTIBLE IS
APPLICABLE AND LESSEE SHALL ONLY BE OBLIGATED TO REIMBURSE LESSOR FOR THE
AMORTIZED PORTION OF THE DEDUCTIBLE AMOUNT THAT OCCURS DURING THE TERM OF THIS
LEASE) FOR ANY INSURANCE OBTAINED BY LESSOR PURSUANT TO 11.3 ABOVE. LESSOR MAY
OBTAIN SUCH INSURANCE FOR THE BUILDING SEPARATELY, OR TOGETHER WITH OTHER
BUILDINGS AND IMPROVEMENTS WHICH LESSOR ELECTS TO INSURE TOGETHER UNDER BLANKET
POLICIES OF INSURANCE. IN SUCH CASE LESSEE SHALL BE LIABLE FOR ONLY SUCH
PORTION OF THE PREMIUMS FOR SUCH BLANKET POLICIES AS ARE ALLOCABLE TO THE
PREMISES. IT IS UNDERSTOOD AND AGREED THAT LESSEE'S OBLIGATION UNDER THIS
PARAGRAPH SHALL BE PRORATED TO REFLECT THE COMMENCEMENT DATE AND EXPIRATION
DATE OF THIS LEASE.

     11.5 LESSEE AND LESSOR EACH HEREBY WAIVE ANY AND ALL RIGHTS OF RECOVERY
AGAINST THE OTHER, OR AGAINST THE OFFICERS, DIRECTORS, EMPLOYEES, PARTNERS,
AGENTS AND REPRESENTATIVES OF THE OTHER, FOR LOSS OF OR DAMAGE TO THE
PROPERTY OF THE WAIVING PARTY OR THE PROPERTY OF OTHERS UNDER ITS CONTROL,
TO THE EXTENT SUCH LOSS OR DAMAGE IS INSURED AGAINST UNDER ANY INSURANCE
POLICY CARRIED BY LESSOR OR LESSEE HEREUNDER. EACH  PARTY SHALL NOTIFY THEIR
RESPECTIVE INSURANCE CARRIERS OF THIS WAIVER.
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ABANDONMENT

     12. Lessee shall not abandon the Premises at any time during the term; and
if Lessee shall abandon, or surrender the premises, or be dispossessed by
process of law, or otherwise, any personal property belonging to Lessee and
left on the Premises shall be deemed to be abandoned, at the option of Lessor,
except such property as may be mortgaged to Lessor.

FREE FROM LIENS

     13. Lessee shall keep the Premises and the property in which the Premises
are situated, free from any liens arising out of any work performed, materials
furnished, or obligations incurred by Lessee.

COMPLIANCE WITH GOVERNMENTAL REGULATIONS

     14. Lessee shall at his sole cost and expense, comply with all of the
requirements of all Municipal, State and Federal authorities now in force, or
which may hereafter be in force, pertaining to the Premises, and shall
faithfully observe in the use of the Premises all Municipal ordinances and State
and Federal statutes now in force or which may hereafter be in force. The
judgment of any court of competent jurisdiction, or the admission of Lessee in
any action or proceeding against Lessee, whether Lessor be a party thereto or
not, that Lessee has violated any such ordinance or statute in the use of the
Premises, shall be conclusive of that fact as between Lessor and Lessee.

INDEMNIFICATION OF LESSOR AND LESSEE'S LIABILITY INSURANCE

     15. The Lessee, as a material part of the consideration to be rendered to
the Lessor, hereby waives all claims against the Lessor for damages to goods,
wares and merchandise, and all other personal property in, upon, or about the
Premises and for injuries to persons including employees, agents and guests in
or about the Premises, from any cause arising at any time, excepting claims
arising from the Lessor's negligence, and the Lessee will hold the Lessor exempt
and harmless from any damage or injury to any person, or to the goods, wares and
merchandise and all other personal property of any person, arising from the use
of the Premises by the Lessee, or from the failure of the Lessee to keep the
Premises in good condition and repair, as herein provided. SEE REVISED
INSURANCE CLAUSE ATTACHED

ADVERTISEMENTS AND SIGNS

     16. Lessee will not place or permit to be placed, in, upon or about the
Premises any unusual or extraordinary signs, or any signs not approved by the
city or other governing authority. The Lessee will not place, or permit to be
placed, upon the Premises, any signs, advertisements or notices without the
written consent of the Lessor first had and obtained. Any sign so placed on the
Premises shall be so placed upon the understanding and agreement that Lessee
will remove same at the termination of the tenancy herein created and repair any
damage or injury to the Premises caused thereby, and if not so removed by Lessee
then Lessor may have same so removed at Lessee's expense.

UTILITIES

     17.  Lessee shall pay for all water, gas, heat, light, power, telephone
service and all other service supplied to the Premises.

ATTORNEY'S FEES

     18.  In case suit should be brought for the possession of the Premises, for
the recovery of any sum due hereunder, or because of the breach of any other
covenant herein, the losing party shall pay to the prevailing party a
reasonable attorney's fee, which shall be deemed to have accrued on the
commencement of such action and shall be enforceable whether or not such action
is prosecuted to judgment.

DEFAULT

     19.  In the event of any breach of this Lease by the Lessee, or an
abandonment of the Premises by the Lessee, the Lessor has the option of 1)
removing all persons and property from the Premises and repossessing the
Premises in which case any of the Lessee's property which the Lessor removes
from the Premises may be stored in a public warehouse or elsewhere at the cost
of, and for the account of Lessee, or 2) allowing the Lessee to remain in full
possession and control of the Premises. If the Lessor chooses to repossess the
Premises, the Lease will automatically terminate in accordance with provisions
of the California Civil Code, Section 1951.2. In the event of such termination
of the Lease, the Lessor may recover from the Lessee: 1) the worth at the time
of award of the unpaid rent which had been earned at the time of termination
including interest at 7% per annum; 2) 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 award exceeds the amount of such rental loss that the Lessee
proves could have been reasonably avoided including interest at 7% per annum; 3)
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 4) any other amount
necessary to compensate the Lessor for all the detriment proximately caused by
the Lessee's failure to perform his obligations under the Lease or which in the
ordinary course of things would be likely to result therefrom. If the Lessor
chooses not to repossess the premises, but allows the Lessee to remain in full
possession and control of the Premises, then in accordance with provisions of
the California Civil Code, Section 1951.4, the Lessor may treat the Lease as
being in full force and effect, and may collect from the Lessee all rents as
they become due through the termination date of the Lease as specified in the
lease. For the purposes of this paragraph, the following do not constitute a
termination of Lessee's right to possession: a) Acts of maintenance or
preservation or efforts to relet the property. b) The appointment of a receiver
on the initiative of the Lessor to protect his interest under this Lease. THE
FOREGOING NOT WITHSTANDING LESSEE SHALL HAVE AFTER WRITTEN NOTICE FIVE (5)
BUSINESS DAYS TO CURE ANY MONETARY BREACH AND THIRTY (30) DAYS TO CURE ANY
NON-MONETARY BREACH.

LATE CHARGES

     20.  Lessee hereby acknowledges that late payment by Lessee to Lessor of
rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this lease, the exact amount of which will be extremely
difficult to ascertain. Such costs include, but are not limited to, processing
and accounting charges, and late charges which may be imposed on Lessor by the
terms of any mortgage or trust deed covering the Premises. Accordingly, if any
installment of rent or any other sum due from Lessee shall not be received by
Lessor or Lessor's designee within ten (10) days after such amount shall be
due, Lessee shall pay to Lessor a late charge equal to ten percent (10%) of
such overdue amount. The parties hereby agree that such late charge represents
a fair and reasonable estimate of the costs Lessor will incur by reason of late
payment by Lessee. Acceptance of such late charge by Lessor shall in no event
constitute a waiver of

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Lessee's default with respect to such overdue amount, nor prevent Lessor from
exercising any of the other rights and remedies granted hereunder.

SURRENDER OF LEASE

     21. The voluntary or other surrender of this Lease by Lessee, or a mutual
cancellation thereof, shall not work a merger, and shall, at the option of
Lessor, terminate all or any existing subleases or subtenancies, or may, at the
option of Lessor, operator as an assignment to him of any or all such
subleases or subtenancies.

TAXES

     22. The Lessee shall be liable for all taxes levied against personal
property and trade or business fixtures. The Lessee also agrees to pay, as an
additional rental, during the term of this Lease and any extensions thereof, all
real estate taxes including supplemental tax bills (whether or not such
supplemental bills are for installment periods prior to the commencement date
of this Lease) plus the yearly installments of any special assessments which are
of record of which may become of record during the term of this lease. If said
taxes and assessments are assessed against the entire building and building
site, and this Lease does not cover the entire building or building site, the
taxes and assessment installments allocated to the Premises shall be pro-rated
on a square footage or other equitable basis, as calculated by the Lessor. It is
understood and agreed that the Lessee's obligation under this paragraph will be
pro-rated to reflect the commencement and termination dates of this Lease.

NOTICES

     23. All notices to be given to Lessee may be given in writing personally or
by depositing the same in the United States mail, postage prepaid, and addressed
to Lessee at the said Premises, whether or not Lessee has departed from,
abandoned or vacated the Premises.

ENTRY BY LESSOR

     24. Lessee shall permit Lessor and his agents to enter into and upon the
Premises at all reasonable times with reasonable notice and with an escort
except in a case of emergency for the purpose of inspecting the same or for the
purpose of maintaining the building in which the Premises are situated, or for
the purpose of making repairs, alterations or additions to any other portion of
said building, including the erection and maintenance of such scaffolding,
canopies, fences and props as may be required without any rebate of rent and
without any liability to Lessee for any loss of occupation or quiet enjoyment
of the Premises thereby occasioned; and shall permit Lessor and his agents, at
any time within ninety days prior to the expiration of this Lease, to place
upon the Premises any usual or ordinary "For Sale" or "To Lease" signs and
exhibit the Premises to prospective tenants at reasonable hours.

DESTRUCTION OF PREMISES

     25. In the event of a partial destruction of the Premises during the said
term from any cause covered by insurance maintained hereunder Lessor shall
forthwith repair the same, provided such repairs can be made within ninety (90)
days under the laws and regulations of State, Federal, County or Municipal
authorities, but such partial destruction shall in no way annul or void this
Lease, except that Lessee shall be entitled to a proportionate reduction of
rent while such repairs are being made, such proportionate reduction to be
based upon the extent to which the making of such repairs shall interfere with
the business carried on by Lessee in the Premises. If such repairs cannot be
made in ninety (90) days, Lessor may, at his option, make same within a
reasonable time, this Lease continuing in full force and effect and the rent to
be proportionately reduced as aforesaid in this paragraph provided. In the
event that Lessor does not so elect to make such repairs which cannot be made
in ninety (90) days, or such repairs cannot be made under such laws and
regulations, this Lease may be terminated at the option of either party. In
respect to any partial destruction which Lessor is obligated to repair or may
elect to repair under the terms of this paragraph, the provision of Section
1932, Subdivision 2, and of Section 1933, Subdivision 4, of the Civil Code of
the State of California are waived by Lessee. In the event that the building in
which the Premises may be situated be destroyed to the extent of not less than
33 1/3% of the replacement cost thereof, Lessor may elect to terminate this
Lease, whether the Premises be injured or not. A total destruction of the
building in which the Premises may be situated shall terminate this Lease. In
the event of any dispute between Lessor and Lessee relative to the provisions
of this paragraph, they shall each select an arbitrator, the two arbitrators so
selected shall select a third arbitrator and the three arbitrators so selected
shall hear and determine the controversy and their decision thereon shall be
final and binding upon both Lessor and Lessee, who shall bear the cost of such
arbitration equally between them.

ASSIGNMENT AND SUBLETTING

     26. The Lessee shall not assign, transfer, or hypothecate the leasehold
estate under this Lease, or any interest therein, and shall not sublet the
Premises, or any part thereof, or any right or privilege appurtenant thereto,
or suffer any other person or entity to occupy or use the Premises, or any
portion thereof, without, in each case, the prior written consent of the Lessor
whose consent shall not be unreasonably withheld. As a condition for granting
its consent to any subletting the Lessor may require the Lessee to agree to pay
to the Lessor, as additional rental, all rents received by the Lessee from its
Sublessee which are in excess of the amount payable by the Lessee to the Lessor
hereunder. The Lessee shall, by sixty (60) days written notice, advise the
Lessor of its intent to sublet the Premises or any portion thereof for any part
of the term hereof. Within thirty (30) days after receipt of Lessee's notice,
Lessor shall either give approval to Lessee to sublease the portion of the
Premises described in Lessee's notice, or Lessor shall terminate this Lease as
to the portion of the Premises described in Lessee's notice on the date
specified in Lessee's notice. If Lessee intends to sublet the entire Premises
and Lessor elects to terminate this Lease, this Lease shall be terminated on
the date specified in Lessee's notice. If, however, this Lease shall terminate
pursuant to the foregoing with respect to less than all the Premises, the rent,
as defined and reserved herein-above shall be adjusted on a prorata basis to
the number of square feet retained by Lessee, and this Lease as so amended
shall continue in full force and effect. If the Lessor approves a subletting,
the Lessee may sublet immediately after receipt of the Lessor's written
approval. In the event Lessee is allowed to assign, transfer or sublet the
whole or any part of the Premises, with the prior written consent of Lessor, no
assignee, transferee or sublessee shall assign or transfer this Lease, either
in whole or in part, or sublet the whole or any part of the Premises, without
also having obtained the prior written consent of the Lessor. A consent of
Lessor to one assignment, transfer, hypothecation, subletting, occupation or
use by any other person shall not release Lessee from any of Lessee's
obligations hereunder or be deemed to be a consent to any subsequent similar or
dissimilar assignment, transfer, hypothecation, subletting, occupation or use
by any other person. Any such assignment, transfer, hypothecation, subletting,
occupation or use without such consent shall be void and shall constitute a
breach of this Lease by Lessee and shall at the option of Lessor exercised by
written notice to Lessee, terminate this Lease. The leasehold estate under this
Lease shall not, nor shall any interest therein, be assignable for any purpose
by operation of law without the written consent of Lessor. As a condition to
its consent, Lessor may require Lessee to pay all expense in connection with
the assignment, and Lessor may require Lessee's assignee or transferee (or
other assignees or transferees) to assume in writing all of the obligations
under this Lease.

     27. If any part of the premises shall be taken for any public or
quasi-public use, under any statute or by right of eminent domain or private
purchase in lieu thereof, and a part thereof remains which is susceptible of
occupation hereunder, this Lease shall, as to the part so taken, terminate as of
the date title shall vest in the condemnor or purchaser, and the rent payable
hereunder shall be adjusted so that the Lessee shall be required to pay for the
remainder of the term only such portion of such rent as the value of the part
remaining after such taking bears to the value of the entire


<PAGE>   6
     Premises prior to such taking; but in such event Lessor shall have the
option to terminate this Lease as of the date when title to the part so taken as
in the condemnor or purchaser. If all of the premises, or such part thereof be
taken so that there does not remain a portion susceptible for occupation
hereunder, this Lease shall thereupon terminate. If a part or all of the
Premises be taken, all compensation awarded upon such taking shall go to the
Lessor and the Lessee shall have no claim thereto.

EFFECT OF CONVEYANCE

     28. The term "Lessor" as used in this Lease, means only the owner for the
time being of the land and building containing the Premises, so that, in the
event of any sale of said land or building, or in the event of a lease of said
building, the Lessor shall be and hereby is entirely freed and relieved of all
covenants and obligations of the Lessor hereunder occurring after said sale and
it shall be deemed and construed, without further agreement between the parties
and the purchase at any such sale, or the Lessee of the building, that the
purchaser or lessee of the building has assumed and agreed to carry out any and
all covenants and obligations of the Lessor hereunder. If any security be given
by the Lessee to secure the faithful performance of all or any of the covenants
of this Lease on the part of the Lessee, the Lessor shall transfer and deliver
the security, as such, to the purchaser at any such sale or the lessee of the
building, and thereupon the Lessor shall be discharged from any further
liability in reference thereto.

SUBORDINATION

     29. Lessee agrees that this Lease may, at the option of Lessor, be subject
and subordinate to any mortgage, deed of trust or other instrument of security
which has been or shall be placed on the land and building or land or building
of which the Premises form a part, and this subordination is hereby made
effective without any further act of Lessee.* The Lessee shall, at any time
hereinafter, on demand, execute any instruments, releases, or other documents
that may be required by any mortgage, mortgagor, or trustor or beneficiary
under any deed of trust for the purpose of subjecting and subordinating this
Lease to the lien of any such mortgage, deed of trust or other instrument of
security,* and the failure of the Lessee to execute any such instruments,
releases or documents, shall constitute a default hereunder.
*provided that the Lessee has received a non-disturbance agreement from
Lessor's lender.

WAIVER

     30. The waiver by Lessor of any breach of any term, covenant or condition,
herein contained shall not be deemed to be a waiver of such term, covenant or
condition or any subsequent breach of the same or any other term, covenant or
condition therein contained. The subsequent acceptance of rent hereunder by
Lessor shall not be deemed to be a waiver of any preceding breach by Lessee of
any term, covenant  or condition of this Lease, other than the failure of
Lessee to pay the particular rental so accepted, regardless of Lessor's
knowledge of such preceding breach at the time of acceptance of such rent.

HOLDING OVER

    31. Any holding over after the expiration of the said term, with consent of
Lessor, shall be construed to be a tenancy from month to month, at a rental to
be negotiated by Lessor and Lessee prior to the expiration of said term, and
shall otherwise be on the terms and conditions herein specified, so far as
applicable.

SUCCESSORS AND ASSIGNS

     32. The covenants and conditions herein contained shall, subject to the
provisions as to assignment, apply to and bind the heirs, successors,
executors, administrators and assigns of all of the parties hereto; and all of
the parties hereto shall be jointly and severally liable hereunder.

TIME

     33. Time is of the essence of this Lease.

MARGINAL CAPTIONS

     34. The marginal headings or titles to the paragraphs of this Lease are
not a part of this Lease and shall have no effect upon the construction or
interpretation of any part thereof. This instrument contains all of the
agreements and conditions made between the parties hereto or their respective
successors in interest.
ADDITIONAL PARAGRAPH 35 IS ATTACHED AND HEREBY MADE A PART OF THIS LEASE.

THIS LEASE HAS BEEN PREPARED FOR SUBMISSION TO YOUR ATTORNEY WHO WILL REVIEW THE
DOCUMENT AND ASSIST YOU TO DETERMINE WHETHER YOUR LEGAL RIGHTS ARE ADEQUATELY
PROTECTED, RENAULT & HANDLEY IS NOT AUTHORIZED TO GIVE LEGAL AND TAX ADVICE. NO
REPRESENTATION OR RECOMMENDATION IS MADE BY RENAULT & HANDLEY OR ITS AGENTS OR
EMPLOYEES AS TO THE LEGAL SUFFICIENCY, LEGAL EFFECT OR TAX CONSEQUENCES OF THIS
DOCUMENT OR ANY TRANSACTION RELATING THERETO. THESE ARE QUESTIONS FOR YOUR
ATTORNEY WITH WHOM YOU SHOULD CONSULT BEFORE SIGNING THIS DOCUMENT.

     IN WITNESS WHEREOF, Lessor and Lessee have executed these presents, the
day and year first above written.

               LESSOR                                  LESSEE

Y.A. TITLE AND RENAULT & HANDLEY              CIDCO INCORPORATED,
EMPLOYEES INVESTMENT CO.                      A DELAWARE CORPORATION

/s/ [SIGNATURE ILLEGIBLE]                     /s/ [SIGNATURE ILLEGIBLE]
----------------------------------            ----------------------------------

/s/ [SIGNATURE ILLEGIBLE]                     /s/  RICHARD D. KENT
----------------------------------            ----------------------------------
                                              V.P. FINANCE, CFO, COO
                                              8/31/98


                                     5 of 5

<PAGE>   7
                              ADDITIONAL PARAGRAPH

This additional paragraph is hereby made a part of that certain Lease dated
August 31, 1998, by and between Y.A. Tittle and Renault & Handley Employees
Investment Co., as Lessor and CIDCO, Incorporated, a Delaware corporation, as
Lessee, covering the Premises at 220 Cochrane Circle, Morgan Hill, California.

     Par. 35. Without Lessor's advance written consent, Lessee shall not bring,
use or permit upon the leased Premises, temporarily or otherwise, or generate
at, or emit any toxic or hazardous substances, including, without limitation,
substances or materials which are listed on any of the Environmental Protection
Agency's lists of hazardous wastes or identified in any statute or regulation
of the State of California dealing with Hazardous wastes as the same may be
amended from time to time. Notwithstanding Lessor's consent, Lessee shall
comply, at its sole cost, with all laws pertaining to, and shall indemnify and
hold Lessor harmless from any claims, liabilities, costs or expenses incurred
or suffered by Lessor arising from such bringing, using, permitting,
generating, or emitting or disposing by Lessee. Lessee's indemnification and
hold harmless obligations for claims caused by Lessee include, without
limitations, (i) claims, liability, costs or expenses resulting from or based
upon administrative, judicial (civil or criminal) action brought by any
private or public person under common law or under any Federal, State, County
or Municipal law, ordinance or regulation, (ii) claims, liabilities, costs or
expenses pertaining to the clean-up or containment of wastes, the
identification of the pollutants or the waste, the identification of scope of
any environmental contamination, the removal of pollutants from soils, river
beds or aquifers, the provisions of an alternative public drinking water
source, or the long-term monitoring of ground water and surface water, and
(iii) all costs or defending such claims.