<PAGE>

                                                                   Exhibit 10_34





                                     LIBERTY
                                 PROPERTY TRUST
<PAGE>

                                 LEASE AGREEMENT

                            (Multi-Tenant Industrial)

INDEX
-----

ss.                             Section                                     Page
---                             -------                                     ----

1.   Summary of Terms & Certain Definitions....................................1

2.   Premises..................................................................2

3.   Acceptance of Premises....................................................2

4.   Use; Compliance...........................................................2

5.   Term......................................................................2

6.   Minimum annual Rent.......................................................3

7.   Operation of Property; Payment of Expenses................................3

8.   Signs.....................................................................4

9.   Alterations and Fixtures..................................................5

10.  Mechanics' Liens..........................................................5

11.  Landlord's Right of Entry.................................................5

12.  Damage by Fire or Other Casualty..........................................5

13.  Condemnation..............................................................6

14.  Non-Abatement of Rent.....................................................6

15.  Indemnification of Landlord...............................................6

16.  Waiver of Claims..........................................................6

17.  Quiet Enjoyment...........................................................6

18.  Assignment and Subletting.................................................7

19.  Subordination; Mortgagee's Rights.........................................7

20.  Recording; Tenant's Certificate...........................................7

21.  Surrender; Abandoned Property.............................................8

22.  Curing Tenant's Certificate...............................................8

23.  Defaults - Remedies.......................................................8

24.  Representations of Tenant.................................................9

25.  Liability of Landlord.....................................................9

26.  Interpretation; Definitions..............................................10

27.  Notices..................................................................10

28.  Security Deposit.........................................................11
<PAGE>

INDEX (RIDER)
-------------

ss.      Section                                                           Page
---      -------                                                           ----

29.      Tenant Improvements                                               R-1

30.      Extension Option                                                  R-2

31.      Compliance                                                        R-4

32.      Operating Expenses                                                R-4

33.      Repairs and Maintenance                                           R-5

34.      Alterations                                                       R-5

35.      Landlord's Right of Entry                                         R-6

36.      Damage by Fire or Other Casualty                                  R-6

37.      Taking                                                            R-6

38.      Indemnification of Tenant                                         R-6

39.      Surrender                                                         R-6

40.      Curing Tenant's Defaults                                          R-6

41.      Defaults - Remedies                                               R-6

42.      Landlord's Authority                                              R-8

43.      Interest                                                          R-8

44.      Default by Landlord                                               R-8

45.      HVAC                                                              R-8

46.      Audit of Landlord's Operating Expense Records                     R-8

47.      Right of First Offer                                              R-9
<PAGE>

         THIS LEASE AGREEMENT is made by and between LIBERTY PROPERTY LE@UTED
PARTNERSHIP, a Pennsylvania limited partnership ("LANDLORD") with its address at
10400 Viking Drive, Suite 130, Eden Prairie, Minnesota 55344, and ANCOR
CONLKMCATIONS, INCORPORATED, a corporation organized under the laws of Minnesota
("TENANT") with its address at 6130 Blue Circle Drive, Minnetonka, Minnesota
55343, and is dated as of the date on which this lease has been fully executed
by Landlord and Tenant.

1.       Summary of Terms and Certain Definitions.


         (a)      "PREMISES": Approximate rentable square feet: 31,821
                  (Section 2)      Suite: 13-21

         (b)      "BUILDING": Approximate rentable square feet: 72,965
                  (ss.2)         Address:   6321-6325 Bury Drive
                                 Eden Prairie, Minnesota 55343

         (c)      "TERM": Seventy-two (72) months plus any partial month from
                  the Commencement (ss.5) Date until the first day of the first
                  full calendar month during the Term

                  (i) "COMMENCEMENT DATE": October 1, 1999 (See Rider)

                  (ii) "EXPIRATION DATE": See Section 5

         (d)      Minimum Rent (ss.6) & Operating Expenses (ss.7)

                  (i) "MINIMUM ANNUAL RENT": $278,433.72 (Two Hundred
                  Seventy-eight Thousand Four Hundred Thirty-three and 72/100
                  Dollars), payable in monthly installments of $23,202.81
                  (Twenty-three Thousand Two Hundred Two and 81/100 Dollars).

                  (ii) Estimated "ANNUAL OPERATING EXPENSES ": $126,329.40 (One
                  Hundred Twenty- six Thousand Three Hundred Twenty-nine and
                  40/100 Dollars), payable in monthly installments of $10,527.45
                  (Ten Thousand Five Hundred Twenty-seven and 45/100 Dollars),
                  based on estimated 1999 operating expenses of $3.97 per square
                  foot, subject to adjustment (ss.7(a))

         (e)      "PROPORTIONATE SHARE" (ss.7(a)): 43.61% (Ratio of approximate
                  rentable square feet in the Premises to approximate rentable
                  square feet in the Building)

         (f)      "USE" (ss.4)- Office and light manufacturing

         (g)      "SECURITY DEPOSIT" (ss.28): $45,000.00 (Forty-five Thousand
                  and no/l00 Dollars)

         (h)      CONTENTS: This lease consists of the Index, pages 1 through 11
                            containing Sections 1 through 28 and the following,
                            all of which are attached hereto and made a part of
                            this lease:
                            Rider with Sections 29 through 47;
                            Exhibits: "A" - Plan showing Premises
                                      "B" - Commencement Certificate Form
                                      "C" - Building Rules
                                      "D" - Estoppel Certificate Form
                                      "E" - Tenant Improvement Plans
<PAGE>

2. Premises. Landlord hereby leases to Tenant and Tenant hereby leases from
Landlord the Premises as shown an attached Exhibit "A" within the Building (the
Building and the lot on which it is located, the "PROPERTY"). together with the
non- exclusive right with Landlord and other occupants of the Building to use
all area and facilities provided by Landlord for the use of all tenants in the
Property including any driveways, sidewalks and parking, loading and landscaped
areas (the "COMMON AREAS").

3. Acceptance of Premises. Tenant has examined and knows the condition of the
Property, the zoning, streets, sidewalks. parking areas. curbs and access ways
adjoining it, visible easements, any surface conditions and the present uses.
and Tenant accepts them in the condition in which they now are, without relying
on any representation, covenant or warranty by Landlord. Tenant and its agents
shall have the right. at Tenant's own risk, expense and responsibility. at all
reasonable times prior to the Commencement Date. to enter the Premises for the
purpose of taking measurements and installing its furnishings and equipment.
provided that the Premises are vacant and Tenant obtains Landlord's prior
written consent.

4. Use; Compliance.

       (a) Permitted Use. Tenant shall occupy and use the Premises for and only
for the Use specified in Section l(f) above and in such a manner as is lawful,
reputable and will not create any nuisance or otherwise interfere with any other
tenant's normal operations or the management of the Building. Without limiting
the foregoing, such Use shall exclude any use that would cause the Premises or
the Property to be deemed a "place of public accommodation" under the Americans
with Disabilities Act (the "ADA") as further described in the Building Rules
(defined below). All Common Areas shall be subject to Landlords exclusive
control and management at all times. Tenant shall not use or permit the use of
any portion of the Property for outdoor storage or installations outside of the
Premises nor for any use that would interfere with any other person's use of any
portion of the Property outside of the Premises.

       (b) Compliance. Landlord represents that, as of the date of this lease,
there is no action required with respect to the Premises or Common areas under
any laws (including Title III of the ADA), ordinances, notices, orders, rules,
regulations and requirements applicable to the Premises or to the Common Areas.
From and after the Commencement Date, Tenant shall comply promptly, at its sole
expense. (including making any alterations or improvements) with all laws
(including the ADA), ordinances, notices. orders, rules. regulations and
requirements regulating the Property during the Term which impose any duty upon
Landlord or Tenant with respect to Tenant's use, occupancy or alteration of, or
Tenant's installations in or upon, the Property including the Premises, (as the
same may be amended the "LAWS AND REQUIREMENTS") and the building rules attached
as Exhibit "C", as amended by Landlord from time to time (the "BUILDING RULES").
Provided, however, that Tenant shall not be required to comply with the Laws and
Requirements with respect to the footings, foundations, structural steel columns
and girders forming a pan of the Property unless the need for such compliance
arises out of Tenant's use, occupancy or alteration of the Property, or by any
act or omission of Tenant or any employees, agents, contractors. licensees or
invitees ("AGENTS") of Tenant. With respect to Tenant's obligations as to the
Property, other than the Premises, at Landlords option and at Tenant's expense,
Landlord may comply with any repair. replacement or other construction
requirements of the Laws and Requirements and Tenant shall pay to Landlord all
costs thereof as additional rent.

       (c) Environmental. Tenant shall comply, at its sole expense. with all
Laws and Requirements as set forth above. all manufacturers' instructions and
all requirements of insurers relating to the treatment, production, storage,
handling, transfer. processing. transporting, use, disposal and release of
hazardous substances, hazardous mixtures, chemicals, pollutants. petroleum
products, toxic or radioactive matter (the "RESTRICTED ACTIVITIES"). Tenant
shall deliver to Landlord copies of all Material Safety Data Sheets or other
written information prepared by manufacturers, importers or suppliers of any
chemical and all notices, filings, permits and any other written communications
from or to Tenant and any entity regulating any Restricted Activities.

       (d) Notice. If at any time during or after the Term, Tenant becomes aware
of any inquiry, investigation or proceeding regarding the Restricted Activities
or becomes aware of any claims, actions or investigations regarding the ADA,
Tenant shall gave Landlord written notice, within 5 days after first learning
thereof, providing all available information and copies of any notices.

5. Term. The Term of this lease shall commence on the Commencement Date and
shall end at 11:59 p.m. on the last day of the Term (the "EXPIRATION DATE"),
without the necessity for notice from either party, unless sooner terminated in
accordance with the terms hereof. At Landlords request, Tenant shall confirm the
Commencement Date and Expiration Date by executing a lease commencement
certificate in the form attached as Exhibit "B".

6. Minimum Annual Rent. Tenant agrees to pay to Landlord the Minimum Annual Rent
in equal monthly installments in the amount set forth in Section t(d) (as
increased at the beginning of each lease year as set forth in Section l(d)), in
advance. on the first day of each calendar month during the Term, without
notice, demand or setoff, at Landlords address designated at the beginning of
this lease unless Landlord designates otherwise-, provided that rent for the
first full month shall be paid at the signing of this lease. If the Commencement
Date falls on a day other than the first day of a calendar month, the rent shall
be apportioned pro rata on a per them basis for the period from the Commencement
Date until the first day of the following calendar month and shall be paid on or
before the Commencement Date. As used in this lease, the term "lease year" means
the period from the Commencement Date through


                                       2
<PAGE>

the succeeding 12 full calendar months (including for the first lease year any
partial month from the Commencement Date until the first day of the first full
calendar month) and each successive 12 month period thereafter during the Term.

7. Operation of Property, Payment of Expenses.

      (a) Payment of Operating Expenses. Tenant shall pay to Landlord the Annual
Operating Expenses in equal monthly installments in the amount set forth in
Section l(d) (prorated for any partial month), from the Commencement Date and
continuing throughout the Term on the first day of each calendar month during
the Term, as additional rent, without notice. demand or setoff. provided that
the monthly installment for the first full month shall be paid at the signing of
this lease. Landlord shall apply such payments to the operating expenses owed to
Landlord by Tenant pursuant to the following Sections 7(b@-(f), The amount of
the .Annual Operating Expenses set forth in Section l(d) represents Tenant's
Proportionate Share of the estimated operating expenses during the first
calendar year of the Term on an annualized basis, from time to time Landlord may
adjust such estimated amount if the estimated operating expenses increase. By
April 30th of each year (and as soon as practical after the expiration or
termination of this lease or at any time in the event of a sale of the
Property), Landlord shall provide Tenant with a statement of the actual amount
of such expenses for the preceding calendar year or part thereof. Landlord or
Tenant shall pay to the other the amount of any deficiency or overpayment then
due from one to the other or, at Landlord's option, Landlord may credit Tenant's
account for any overpayment. Tenant's obligation to pay the Annual Operating
Expenses pursuant to this Section 7 shaft survive the expiration or termination
of this lease.

      (b) Taxes and Other Impositions. Tenant shall pay prior to delinquency all
levies. taxes (including sales taxes and gross receipt taxes), assessments,
liens, license and permit fees, which are applicable to the Term, and which are
imposed by any authority or under any law, ordinance or regulation thereof, or
pursuant to any recorded covenants or agreements, and the reasonable cost of
contesting any of the foregoing (the "IMPOSITIONS") upon or with respect to the
Premises, or any improvements thereto, or directly upon this lease or the Rent
(defined in Section 7(f)) or amounts payable by any subtenants or other
occupants of the Premises, or against Landlord because of Landlords estate or
interest herein. Additionally, Tenant shall pay as aforesaid its Proportionate
Share of any Imposition which is not imposed upon the Premises as a separate
entity but which is imposed upon all or part of the Property or upon the leases
or rents relating to the Property.

           (i) Nothing herein contained shall be interpreted as requiring Tenant
to pay any income, excess profits or corporate capital stock tax imposed or
assessed upon Landlord, unless such tax or any similar tax is levied or assessed
in lieu of all or any part of any Imposition or an increase in any Imposition,

           (ii) If it shall not be lawful for Tenant to reimburse Landlord for
any of the Impositions, the Minimum Annual Rent shall be increased by the amount
of the portion of such Imposition allocable to Tenant, unless prohibited by law.

      (c) Insurance.

           (i) Property. Landlord shall keep in effect, and Tenant shall pay to
Landlord its Proportionate Share of the cost of. insurance against loss or
damage to the Building or the Property by fire and such other casualties as may
be included within fire. extended coverage and special form insurance covering
the full replacement cost of the Building (but excluding coverage of Tenant's
personal property in, and any alterations by Tenant to, the Premises), and such
other insurance as Landlord may reasonably deem appropriate or as may be
required from time-to-time by any mortgagee.

           (ii) Liability. Tenant, at its own expense, shall keep in effect
comprehensive general public liability insurance with respect to the Premises
and the Property, including contractual liability insurance, with such limits of
liability for bodily injury i including death) and property damage as reasonably
may be required by Landlord from time-to-time, but not less than a combined
single limit of $1,000,000 per occurrence and a general aggregate limit of not
less than $3,000,000 (which aggregate limit shall apply separately to each of
Tenant's locations if more than the Premises); however, such limits shall not
limit the liability of Tenant hereunder. The policy of comprehensive general
public liability insurance also shall name Landlord and Landlords agent as
insured parties with respect to the Premises, shall be written on an
"occurrence" basis and not on a "claims made" basis, shall provide that it is
primary with respect to any policies carried by Landlord and that any coverage
carried by Landlord shall be excess insurance, shall provide that it shall not
be cancelable or reduced without at least 30 days prior written notice to
Landlord and shall be issued in form satisfactory to Landlord. The insurer shall
be a responsible insurance carrier which is authorized to issue such insurance
and licensed to do business in the state in which the Property is located and
which has at all times during the Term a rating of no less than A VII in the
most current edition of Best's Insurance Reports. Tenant shall deliver to
Landlord on or before the



                                       3
<PAGE>

Commencement Date, and subsequently renewals of, a certificate of insurance
evidencing such coverage and the waiver of subrogation described below.

           (iii) Waiver of Subrogation. Landlord and Tenant shall have included
in their respective property insurance policies waivers of their respective
insurers' right of subrogation against the other party. If such a waiver should
be unobtainable or unenforceable, then such policies of insurance shall state
expressly that such policies shall not be invalidated if, before a casualty, the
insured waives the right of recovery against any party responsible for a
casualty covered by the policy.

           (iv) Increase of Premiums. Tenant agrees not to do anything or fail
to do anything which will increase the cost of Landlords insurance or which will
prevent Landlord from procuring policies (including public liability) from
companies and in a form satisfactory to Landlord. If any breach of the preceding
sentence by Tenant causes the rate of fire or other insurance to be increased,
Tenant shall pay the amount of such increase as additional rent promptly upon
being billed.

     (d) Repairs and Maintenance; Common Areas; Building Management. Except as
specifically otherwise provided in this Section (d), Tenant at its sole expense
shall maintain the Premises in good order and condition, promptly make all
repairs necessary to maintain such condition, and repair any damage to the
Premises caused by Tenant or its Agents. All repairs made by Tenant shall
utilize materials and equipment which are comparable to those originally used in
constructing the Building and Premises. When used in this Section (d), the term
"repairs" shall include replacements and renewals when necessary.

           (i) Landlord, at its sole expense, shall make all necessary repairs
to the footings, foundations, structural steel columns and girders forming a
part of the Premises, provided that Landlord shall have no responsibility to
make any repair until Landlord receives written notice of the need for such
repair.

           (ii) Landlord, at Tenant's sole expense, shall maintain and repair
the HVAC systems appurtenant to the Premises.

           (iii) Landlord shall make all necessary repairs to the roof, exterior
portions of the Premises and the Building, utility and communications lines,
equipment and facilities in the Building, which serve more than one tenant, and
to the Common Areas, the cost of which shall be an operating expense of which
Tenant shall pay its Proportionate Share, provided that Landlord shall have no
responsibility to make any repair until Landlord receives written notice of the
need for such repair. Landlord shall operate and manage the Property and shall
maintain all Common Areas and any paved areas appurtenant to the Property in a
clean and orderly condition. Landlord reserves the right to make alterations to
the Common Areas from time to time. Operating expenses also shall include (A)
all sums expended by Landlord for the supervision, maintenance, repair,
replacement and operation of the Common .areas (including the costs of utility
services), (B) any costs of building improvements made by Landlord to the
Property that are required by any governmental authority or for the purpose of
reducing operating expenses and (C) a management and administrative fee
applicable to the overall operation of the Property.

           (iv) Notwithstanding anything herein to the contrary, repairs and
replacements to the Property including the Premises made necessary by Tenant's
use, occupancy or alteration of, or Tenant's installation in or upon the
Property or by any act or omission of Tenant or its Agents shall be made at the
sole expense of Tenant to the extent not covered by any applicable insurance
proceeds paid to Landlord. Tenant shall not bear the expense of any repairs or
replacements to the Property arising out of or caused by any other tenant's use,
occupancy or alteration of, or any other tenant's installation in or upon, the
Property or by any act or omission of any other tenant or any other tenant's
Agents.

      (e) Utility Charges. Tenant shall pay for water, sewer, gas, electricity,
heat, power, telephone and other communication services and any other utilities
supplied to or consumed in or an the Premises. Landlord shall not be responsible
or liable for any interruption in utility service, nor shall such interruption
affect the continuation or validity of this lease.

      (f) Net lease. Except for the obligations of Landlord expressly set forth
herein, this lease is a "triple net lease" and Landlord shall receive the
Minimum Annual Rent as net income from the Premises, not diminished by any
expenses other than payments under any mortgages, and Landlord is not and shall
not be required to render any services of any kind to Tenant. The term "RENT" as
used in this lease means the Minimum Annual Rent, Annual Operating Expenses and
any other additional rent or sums payable by Tenant to Landlord pursuant to this
lease, all of which shall be deemed rent for purposes of Landlords rights and
remedies with respect thereto. Tenant shall pay all Rent to Landlord within 30
days after Tenant is billed, unless otherwise provided in this lease, and
interest shall accrue on all sums due but unpaid.

8. Signs. Except for signs which are located wholly within the interior of the
Premises and not visible from the exterior of the Premises, no signs shall be
placed on the Property without the prior written consent of Landlord. All signs
installed by Tenant shall be


                                       4
<PAGE>

maintained by Tenant in good condition and Tenant shall remove all such signs at
the termination of this lease and shall repair any damage caused by such
installation, existence or removal.

9. Alterations and Fixtures.

      (a) Subject to Section 10, Tenant shall have the right to install its
trade fixtures in the Premises, provided that no such installation or removal
thereof shall affect any structural portion of the Property nor any utility
lines, communications lines. equipment or facilities in the Building serving any
tenant other than Tenant. At the expiration or termination of this lease and at
the option of Landlord or Tenant, Tenant shall remove such installation(s) and,
in the event of such removal, Tenant shall repair any damage caused by such
installation or removal; if Tenant, with Landlord's written consent, elects not
to remove such installation(s) at the expiration or termination of this lease,
all such installations shall remain on the Property and become the property of
Landlord without payment by Landlord.

      (b) Except for non-structural changes which do not exceed $5000 in the
aggregate, Tenant shall not make or permit to be made any alterations to the
Premises without Landlord's prior written consent. Tenant shall pay the costs of
any required architectural/engineering reviews. In making any alterations, (i)
Tenant shall deliver to Landlord the plans, specifications and necessary
permits. together with certificates evidencing that Tenant's contractors and
subcontractors have adequate insurance coverage naming Landlord and Landlord's
agent as additional insureds, at least 10 days prior to commencement thereof,
(ii) such alterations shall not impair the structural strength of the Building
or any other improvements or reduce the value of the Property or affect any
utility lines, communications lines, equipment or facilities in the Building
serving any tenant other than Tenant, (ill) Tenant shall comply with Section 10
and (iv) the occupants of the Building and of any Adjoining property shall not
be disturbed thereby. All alterations to the Premises by Tenant shall be the
property of Tenant until the expiration or termination of this lease; at that
time all such alterations shall remain on the Property and become the property
of Landlord without payment by Landlord unless Landlord gives written notice to
Tenant to remove the same, in which event Tenant will remove such alterations
and repair any resulting damage. At Tenant's request prior to Tenant making any
alterations, Landlord shall notify Tenant in writing, whether Tenant is required
to remove such alterations at the expiration or termination of this lease

10. Mechanics' Liens. Tenant shall pay promptly any contractors and materialmen
who supply labor, work or materials to Tenant at the Property and shall take all
steps permitted by law in order to avoid the imposition of any mechanic's lien
upon all or any portion of the Property. Should any such lien or notice of lien
be filed for work performed for Tenant other than by Landlord. Tenant shall bond
against or discharge the same within 5 days after Tenant has notice that the
lien or claim is filed regardless of the validity of such lien or claim. Nothing
in this lease is intended to authorize Tenant to do or cause any work to be done
or materials to be supplied for the account of Landlord, all of the same to be
solely for Tenant's account and at Tenant's risk and expense. Throughout this
lease the term "mechanic's lien" is used to include any lien, encumbrance or
charge levied or imposed upon all or any portion of, interest in or income from
the Property on account of any mechanic's, laborer's, materialman's or
construction lien or arising out of any debt or liability to or any claim of any
contractor, mechanic, supplier, materialman or laborer and shall include any
mechanic's notice of intention to file a lien given to Landlord or Tenant, any
stop order given to Landlord or Tenant, any notice of refusal to pay naming
Landlord or Tenant and any injunctive or equitable action brought by any person
claiming to be entitled to any mechanic's lien.

11. Landlord's Right of Entry. Tenant shall permit Landlord and its Agents to
enter the Premises at all reasonable times following reasonable notice (except
in the event of an emergency), for the purpose of inspection, maintenance or
making repairs. alterations or additions as well as to exhibit the Premises for
the purpose of sale or mortgage and, during the last 12 months of the Term, to
exhibit the Premises to any prospective tenant. Landlord will make reasonable
efforts not to inconvenience Tenant in exercising the foregoing rights, but
shall not be liable for any loss of occupation or quiet enjoyment thereby
occasioned.

12. Damage by Fire or Other Casualty.

        (a) If the Premises or Building shall be damaged or destroyed by fire or
other casualty, Tenant promptly shall notify Landlord and Landlord, subject to
the conditions set forth in this Section 12, shall repair such damage and
restore the Premises to substantially the same condition in which they were
immediately prior to such damage or destruction, but not including the repair,
restoration or replacement of the fixtures or alterations installed by Tenant.
Landlord shall notify Tenant in writing, within 30 days after the date of the
casualty, if Landlord anticipates that the restoration will take more than 180
days from the date of the casualty to complete, in such event, either Landlord
or Tenant may terminate this lease effective as of the date of casualty by
giving written notice to the other within 10 days after Landlords notice.
Further, if a casualty occurs during the last 12 months of the Term or any
extension thereof. Landlord may cancel this lease unless Tenant has the right to
extend the Term for at least 3 more years and does so within 30 days after the
date of the casualty.


                                       5
<PAGE>

      (b) Landlord shall maintain a 12 month rental coverage endorsement or
other comparable form of coverage as part of its fire, extended coverage and
special form insurance. Tenant will receive an abatement of its Minimum Annual
Rent and Annual Operating Expenses to the extent the Premises are rendered
untenantable as determined by the carrier providing the rental coverage
endorsement

13. Condemnation

      (a) Termination. If (i) all of the Premises are taken by a condemnation or
otherwise for any public or quasi-public use. (ii) any part of the Premises is
so taken and the remainder thereof is insufficient for the reasonable operation
of Tenant's business or (iii) any of the Property is so taken, and, in Landlords
opinion, it would be impractical or the condemnation proceeds are insufficient
to restore the remainder of the Property, then this lease shall terminate and
all unaccrued obligations hereunder shall cease as of the day before possession
is taken by the condemnor.

      (b) Partial Taking. If there is a condemnation and this lease has not been
terminated pursuant to this Section, (i) Landlord shall restore the Building and
the improvements which are a part of the Premises to a condition and size as
nearly comparable as reasonably possible to the condition and size thereof
immediately prior to the date upon which the condemnor took possession and (ii)
the obligations of Landlord and Tenant shall be unaffected by such condemnation
except that there shall be an equitable abatement of the Minimum Annual Rent
according to the rental value of the Premises before and after the date upon
which the condemnor took possession and/or the date Landlord completes such
restoration.

      (c) Award. In the event of a condemnation affecting Tenant, Tenant shall
have the right to make a claim against the condemnor for moving expenses and
business dislocation damages to the extent that such claim does not reduce the
sums otherwise payable by the condemnor to Landlord. Except as aforesaid and
except as set forth in (d) below, Tenant hereby assigns all claims against the
condemnor to Landlord.

      (d) Temporary Taking. No temporary taking of the Premises shall terminate
this lease or give Tenant any right to any rental abatement. Such a temporary
taking will be treated as if Tenant had sublet the Premises to the condemnor and
had assigned the proceeds of the subletting to Landlord to be applied on account
of Tenant's obligations hereunder. Any award for such a temporary taking during
the Term shall be applied first, to Landlord's costs of collection and, second,
on account of sums owing by Tenant hereunder, and if such amounts applied on
account of sums owing by Tenant hereunder should exceed the entire amount owing
by Tenant for the remainder of the Term. the excess will be paid to Tenant.

14. Non-Abatement of Rent. Except as otherwise expressly provided as to damage
by fire or other casualty in Section 12(b) and as to condemnation in Section
13(b), there shall be no abatement or reduction of the Rent for any call
whatsoever, and this lease shall not terminate, and Tenant shall not be entitled
to surrender the Premises.

15. Indemnification of Landlord. Subject to Sections 7(c)(iii) and 16, Tenant
will protect, indemnify and hold harmless Landlord and its Agents from and
against any and all claims, actions, damages, liability and expense (including
fees of attorneys, investigators and experts) in connection with loss of life,
personal injury or damage to property in or about the Premises or arising out of
the occupancy or use of the Premises by Tenant or its Agents or occasioned
wholly or in part by any act or emission of Tenant or its .Agents, whether prior
to, during or after the Term, except to the extent such loss, injury or damage
was caused by the negligence of Landlord or its Agents. In case any action or
proceeding is brought against Landlord and/or its Agents by reason of the
foregoing, Tenant. at its expense, shall resist and defend such action or
proceeding, or cause the same to be resisted and defended by counsel i
reasonably acceptable to Landlord and its Agents) designated by the insurer
whose policy covers such occurrence or by counsel designated by Tenant and
approved by Landlord and its Agents. Tenant's obligations pursuant to this
Section 15 shall survive the expiration or termination of this lease.

16. Waiver of Claims. Landlord and Tenant each hereby waives all claims for
recovery against the other for any loss or damage which may be inflicted upon
the property of such party even if such loss or damage shall be brought about by
the fault or negligence of the other party or its Agents; provided, however,
that such waiver by Landlord shall not be effusive with respect to any liability
of Tenant described in Sections 4(c) and 7(d)(iv)

17. Quiet Enjoyment. Landlord covenants that Tenant, upon performing all of its
covenants. agreements and conditions of this lease. shall have quiet and
peaceful possession of the Premises as against anyone claiming by or through
Landlord, subject, however. to the exceptions, reservations and conditions of
this lease.


                                       6
<PAGE>

18. Assignment and Subletting

      (a) Limitation. Tenant shall not transfer this lease, voluntarily or by
operation of law, without the prior written consent of Landlord which shall not
be withheld unreasonably. However Landlords consent shall not be required in the
event of any transfer by Tenant to an affiliate of Tenant which is at least as
creditworthy as Tenant as of the date of this lease and provided Tenant delivers
to Landlord the instrument described in Section (c)(iii) below, together with a
certification of such creditworthiness by Tenant and such affiliate. Any
transfer not in conformity with this Section 18 shall be void at the option of
Landlord, and Landlord may exercise any or all of its rights under Section 23. A
consent to one transfer shall not be deemed to be a consent to any subsequent
transfer. "Transfer" shall include any sublease, assignment, license or
concession agreement, change in ownership or control of Tenant, mortgage or
hypothecation of this lease or Tenants interest therein or in all or a portion
of the Premises.

      (b) Offer to Landlord. Tenant acknowledges that the terms of this lease,
including the Minimum Annual Rent. have been based on the understanding that
Tenant physically shall occupy the Premises for the entire Term. Therefore, upon
Tenant's request to transfer all or a portion of the Premises, at the option of
Landlord, Tenant and Landlord shall execute an amendment to this lease removing
such space from the Premises, Tenant shall be relieved of any liability with
respect to such space and Landlord she have the right to lease such space to any
party, including Tenant's proposed transferee.

      (c) Conditions. Notwithstanding the above, the following shall apply to
any transfer, with or without Landlords consent:

           (i) As of the date of any transfer, Tenant shall not be in default
under this lease nor shall any act or omission have occurred which would
constitute a default with the giving of notice and/or the passage of time.

           (ii) No transfer shall relieve Tenant of its obligation to pay the
Rent and to perform all its other obligations hereunder. The acceptance of Rent
by Landlord from any person shall not be deemed to be a waiver by Landlord of
any provision of this lease or to be a consent to any transfer.

           (iii) Each transfer shall be by a written instrument in form and
substance satisfactory to Landlord which shall (A) include an assumption of
liability by any transferee of all Tenant's obligations and the transferee's
ratification of and agreement to be bound by all the provisions of this lease,
(B) afford Landlord the right of direct action against the transferee pursuant
to the same remedies as are available to Landlord against Tenant and (C) be
executed by Tenant and the transferee.

           (iv) Tenant shall pay, within 10 days of receipt of an invoice which
shall be no less than $250. Landlords reasonable attorneys' fees and costs in
connection with the review, processing and documentation of any transfer for
which Landlords consent is requested.

19. Subordination: Mortgagee's Rights.

      (a) This lease shall be subordinate to any first mortgage or other primary
encumbrance now or hereafter affecting the Premises. Although the subordination
is self-operative, within 10 days after written request, Tenant shall execute
and deliver any further instruments confirming such subordination of this lease
and any further instruments of attornment that may be desired by any such
mortgagee or Landlord. However, any mortgagee may at any time subordinate its
mortgage to this lease, without Tenant's consent. by giving written notice to
Tenant, and thereupon this lease shall be deemed prior to such mortgage without
regard to their respective dates of execution and delivery; provided, however,
that such subordination shall not affect any mortgagee's right to condemnation
awards, casualty insurance proceeds, intervening liens or any right which shall
arise between the recording of such mortgage and the execution of this lease.

      (b) It is understood and agreed that any mortgagee shall not be liable to
Tenant for any funds paid by Tenant to Landlord unless such funds actually have
been transferred to such mortgagee by Landlord.

      (c) Notwithstanding the provisions of Sections 12 and 13 above, Landlord's
obligation to restore the Premises after a casualty or condemnation shall be
subject to the consent and prior rights of Landlords first mortgagee.

20. Recording: Tenant's Certificate. Tenant shall not record this lease or a
memorandum thereof without Landlords prior written consent. Within 10 days after
Landlords written request from time to time:


                                       7
<PAGE>

      (a) Tenant shall execute, acknowledge and deliver to Landlord a written
statement certifying the Commencement Date and Expiration Date of this lease,
that this lease is in full force and effect and has not been modified and
otherwise as set forth in the form of estoppel certificate attached as Exhibit
"D" or with such modifications as may be necessary to reflect accurately the
stated facts and/or such other certifications as may be requested by a mortgagee
or purchaser. Tenant understands that its failure to execute such documents may
cause Landlord serious financial damage by causing the failure of a financing or
sale transaction.

      (b) Tenant shall furnish to Landlord, Landlords mortgagee, prospective
mortgagee or purchaser reasonably requested financial information.

21. Surrender: Abandoned Property.

      (a) Subject to the terms of Sections 9(b), 12(a) and 13(b), at the
expiration or termination of this lease, Tenant promptly shall yield up in the
same condition. order and repair in which they are required to be kept
throughout the Term, the Premises and all improvements thereto, and all fixtures
and equipment servicing the Building ordinary wear and tear excepted.

      (b) Upon or prior to the expiration or termination of this lease, Tenant
shall remove any personal property from the Property. Any personal property
remaining thereafter shall be deemed conclusively to have been abandoned, and
Landlord, at Tenant's expense, may remove, store, sell or otherwise dispose of
such property in such manner as Landlord may see fit and/or Landlord may return
such property as its property. If any part thereof shall be sold, then Landlord
may receive and retain the proceeds of such sale and apply the same, at its
option, against the expenses of the sale, the cost of moving and storage and any
Rent due under this lease.

      (c) If Tenant, or any person claiming through Tenant, shall continue to
occupy the Premises after the expiration or termination of this lease or any
renewal thereof, such occupancy shall be deemed to be under a month-to-month
tenancy under the same terms and conditions set forth in this lease, except that
the monthly installment of the Minimum Annual Rent during such continued
occupancy shall be double the amount applicable to the last month of the Term.
Anything to the contrary notwithstanding, any holding over by Tenant without
Landlords prior written consent shall constitute a default hereunder and shall
be subject to all the remedies available to Landlord

22. Curing Tenant's Defaults. If Tenant shall be in default in the performance
of any of its obligations hereunder, Landlord, without any obligation to do so,
in addition to any other rights it may have in law or equity, may elect to cure
such default on behalf of Tenant after written notice (except in the case of
emergency) to Tenant. Tenant shall reimburse Landlord upon demand for any sums
paid or costs incurred by Landlord in curing such default, including interest
thereon from the respective dates of Landlords incurring such costs, which sums
and costs together with interest shall be deemed additional rent.

23. Defaults - Remedies

      (a)  Defaults. It shall be an event of default:

          (i) If Tenant does not pay in full when due any and all Rent;

          (ii) If Tenant fails to observe and perform or otherwise breaches any
other provision of this lease;

          (iii) If Tenant abandons the Premises, which shall be conclusively
presumed if the Premises remain unoccupied for more than 10 consecutive days, or
removes or attempts to remove Tenants goods or property other than in the
ordinary course of business, or

          (iv) If Tenant becomes insolvent or bankrupt in any sense or makes a
general assignment for the benefit of creditors or offers a settlement to
creditors, or if a petition in bankruptcy or for reorganization or for an
arrangement with creditors under any federal or state law is filed by or against
Tenant, or a bill in equity or other proceeding for the appointment of a
receiver for any of Tenant's assets is commenced, or if any of the real or
personal property of Tenant shall be levied upon; provided, however. that any
proceeding brought by anyone other than Landlord or Tenant under any bankruptcy,
insolvency, receivership or similar law shall not constitute a default until
such proceeding has continued unstayed for more than 60 consecutive days.

      (b) Remedies. Then, and in any such event, Landlord shall have the
following rights:

          (i) To charge a late payment fee equal to the greater of $100 or 5% of
any amount owed to Landlord pursuant to this lease which is not paid within 5
days after the due date.


                                       8
<PAGE>

          (ii) To enter and repossess the Premises, by breaking open locked
doors if necessary, and remove all persons and all or any property therefrom, by
action at law or otherwise, without being liable for prosecution or damages
therefor, and Landlord may,at Landlords option, make alterations and repairs in
order to relet the Remises and relet all or any part(s) of the Premises for
Tenant's account. Tenant agrees to pay to Landlord on demand any deficiency that
may arise by reason of such reletting. In the event of reletting without
termination of this lease, Landlord may at any time thereafter elect to
terminate this lease for such previous breach.

          (iii) To accelerate the whole or any part of the Rent for the balance
of the Term, and declare the same to be immediately due and payable.

          (iv) To terminate this lease and the Term without any right an the
part of Tenant to save the forfeiture by payment of any sum due or by other
performance of any condition, term or covenant broken.

      (c) Grace Period. Notwithstanding anything hereinabove stated, neither
party will exercise any available right because of any default of the other,
except those remedies contained in subsection (b)(i) of this Section, unless
such party shall have first given 10 days written notice thereof to the
defaulting party, and the defaulting party shall have failed to cure the default
within such period. provided, however, that:

          (i) No such notice shall be required if Tenant fails to comply with
the provisions of Sections 10 or 20(a), in the case of emergency as set forth in
Section 22 or in the event of any default enumerated in subsections (a)(iii) and
(iv) of this Section.

          (ii) Landlord shall not be required to give such 10 days notice more
than 2 times during any 12 month period

          (iii) If the default consists of something other than the failure to
pay money which cannot reasonably be cured within 10 days, neither party will
exercise any right if the defaulting party begins to cure the default within the
10 days and continues actively and diligently in good faith to completely cure
said default.

          (iv) Tenant agrees that any notice given by Landlord pursuant to this
Section which is served in compliance with Section 27 shall be adequate notice
for the purpose of Landlords exercise of any available remedies.

      (d) Non-Waiver; Non-Exclusive. No waiver by Landlord of any breach by
Tenant shall be a waiver of any subsequent breach, nor shall any forbearance by
Landlord to seek a remedy for any breach by Tenant be a waiver by Landlord of
any rights and remedies with respect to such or any subsequent breach. Efforts
by Landlord to mitigate the damages caused by Tenant's default shall not
constitute a waiver of Landlords right to recover damages hereunder. No right or
remedy herein conferred upon or reserved to Landlord is intended to be exclusive
of any other right or remedy provided herein or by law. but each shall be
cumulative and in addition to every other right or remedy given herein or now or
hereafter existing at law or in equity. No payment by Tenant or receipt or
acceptance by Landlord of a lesser amount than the total amount due Landlord
under this lease shall be deemed to be other than on account, nor shall any
endorsement or statement on any check or payment be deemed an accord and
satisfaction. and Landlord may accept such check or payment without prejudice to
Landlord's right to recover the balance of Rent due, or Landlord's.
right to pursue any other available remedy.

      (e) Costs and Attorneys' Fees. If either party commences an action against
the other party arising out of or in connection with this lease, the prevailing
party shall be entitled to have and recover from the losing party attorneys'
fees, costs of suit, investigation expenses and discovery costs, including costs
of appeal

24. Representations of Tenant. Tenant represents to Landlord and agrees that:

      (a) The word "Tenant" as used herein includes the Tenant named above as
well as its successors and assigns, each of which shall be under the same
obligations and liabilities and each of which shall have the same rights,
privileges and powers as it would have possessed had it originally signed this
lease as Tenant. Each and every of the persons named above as Tenant shall be
bound jointly and severally by the terms, covenants and agreements contained
herein. However, no such rights, privileges or powers shall inure to the benefit
of any assignee of Tenant immediate or remote, unless Tenant has complied with
the terms of Section 18 and the assignment to such assignee is permitted or has
been approved in writing by Landlord. Any notice required or permitted by the
terms of this lease may be given by or to any one of the persons named above as
Tenant, and shall have the same force and effect as if given by or to all
thereof.

      (b) If Tenant is a corporation, partnership or any other form of business
association or entity, Tenant is duly formed an in good standing, and has full
corporate or partnership power and authority, as the case may be, to enter into
this lease and has taken all


                                       9
<PAGE>

corporate or partnership action, as the case may be, necessary to carry out the
transaction contemplated herein, so that when executed, this lease constitutes a
valid and binding obligation enforceable in accordance with its terms. Tenant
shall provideLandlord with corporate resolutions or other proof in a form
acceptable to Landlord, authorizing the execution of this lease at the time of
such execution.

25. Liability of Landlord. The word "Landlord" as used herein includes the
Landlord named above as well as its successors and assigns, each of which shall
have the same rights, remedies, powers, authorities and privileges as it would
have had it originally signed this lease as Landlord. Any such person or entity,
whether or not named herein, shall have no liability hereunder after it ceases
to hold title to the Premises except for obligations already accrued (and, as to
any unapplied portion of Tenant's Security Deposit. Landlord shall be relieved
of all liability therefor upon transfer of such portion to its successor in
interest) and Tenant shall look solely to Landlords successor in interest for
the performance of the covenants and obligations of the Landlord hereunder which
thereafter shall accrue. Neither Landlord nor any principal of Landlord nor any
owner of the Property, whether disclosed or undisclosed. shall have any personal
liability with respect to any of the provisions of this lease or the Premises,
and if Landlord is in breach or default with respect to Landlord's obligations
under this lease or otherwise, Tenant shall look solely to the equity of
Landlord in the Property for the satisfaction of Tenant's claims.
Notwithstanding the foregoing, no mortgagee or ground lessor succeeding to the
interest of Landlord hereunder (either in terms of ownership or possessory
rights) shall be (a) liable for any previous act or omission of a prior
landlord, (b) subject to any rental offsets or defenses against a prior landlord
or (c) bound by any amendment of this lease made without its written consent, or
by payment by Tenant of Minimum Annual Rent in advance in excess of one monthly
installment.

26. Interpretation: Definitions.

      (a) Captions. The captions in this lease are for convenience only and are
not a part of this lease and do not in any way define, limit, describe or
amplify the terms and provisions of this lease or the scope or intent thereof.

      (b) Entire Agreement This lease represents the entire agreement between
the parties hereto and there are no collateral or oral agreements or
understandings between Landlord and Tenant with respect to the Premises or the
Property. No rights, easements or licenses are acquired in the Property or any
land adjacent to the Property by Tenant by implication or otherwise except as
expressly set forth in the provisions of this lease. This lease shall not be
modified in any manner except by an instrument in writing executed by the
parties. The masculine (or neuter) pronoun and the singular number shall include
the masculine, feminine and neuter genders and the singular and plural number.
The word "including" followed by any specif3c item(s) is deemed to refer to
examples rather than to be words of limitation. Both parties having participated
fully and equally in the negotiation and preparation of this lease, this lease
shall not be more strictly construed, nor any ambiguities in this lease
resolved, against either Landlord or Tenant.

      (c) Covenants. Each covenant, agreement, obligation, term, condition or
other provision herein contained shall be deemed and construed as a separate and
independent covenant of the party bound by, undertaking or making the same, not
dependent on any other provision of this lease unless otherwise expressly
provided. All of the terms and conditions set forth in this lease shall apply
throughout the Term unless otherwise expressly set forth herein.

      (d) Interest. Wherever interest is required to be paid hereunder, such
interest shall be at the highest rate permitted under law but not in excess of
15% per annum.

       (e) Severability, Governing Law. If any provisions of this lease shall be
declared unenforceable in any respect, such unenforceability shall not affect
any other provision of this lease, and each such provision shall be deemed to be
modified. if possible. in such a manner as to render it enforceable and to
preserve to the extent possible the intent of the parties as set forth herein.
This lease shall be construed and enforced in accordance with the laws of the
state in which the Property is located.

       (f) "Mortgage" and "Mortgagee" The word "mortgage" as used herein
includes any lien or encumbrance on the Premises or the Property or on any part
of or interest in or appurtenance to any of the foregoing. including without
limitation any sound rent or ground lease if Landlords interest is or becomes a
leasehold estate. The word "mortgagee" as used herein includes the holder of any
mortgage, including any ground lessor if Landlord's interest is or becomes a
leasehold estate. Wherever any right is even to a mortgagee, that right may be
exercised on behalf of such mortgagee by any representative or servicing agent
of such mortgagee.

       (g) "Person." The word "person" is used herein to include a natural
person, a partnership, a corporation, an association and any other form of
business association or entity.


                                       10
<PAGE>

       (b) Proportionate Share. At any time or times, upon request of Landlord
or of any tenant of the Building the method for allocating Tenant's
Proportionate Share of any Impositions, cost, charge, rent, expense or payment
then or thereafter payable shall be redetermined by an independent qualified
expert. The cost of such redetermination shall be borne by the tenants of the
Building in the same proportion as that determined by such expert for
reallocation of said relevant sum, except that if such redetermination is
requested by a tenant, the cost thereof shall be borne entirely by such tenant
if the proportionate share of said relevant sum allocable to such tenant as the
result of such redetermination shall not vary by at least 5% from the amount
which would have been allocable to such tenant in accordance with the percentage
based on square foot area.

27. Notices. Any notice or other communication under this lease shall be in
writing and addressed to Landlord or Tenant at their respective addresses
specified at the beginning of this lease, except that after the Commencement
Date Tenant's address shall be at the Premises. (or to such other address as
either may designate by notice to the other) with a copy to any mortgagee or
other party designated by Landlord. Each notice or other communication shall be
deemed given if sent by prepaid overnight delivery service or by certified mail,
return receipt requested, postage prepaid or in any other manner, with delivery
in any case evidenced by a receipt, and shall be deemed received on the day of
actual receipt by the intended recipient or on the business day delivery is
refused. The giving of notice by Landlord's attorneys, representatives and
agents under this Section shall be deemed to be the acts of Landlord;. however,
the foregoing provisions governing the date on which a notice is deemed to have
been received shall mean and refer to the date on which a party to this lease,
and not its counsel or other recipient to which a copy of the notice may be
sent, is deemed to have received the notice.

28. Security Deposit. At the time of signing this lease, Tenant shall deposit
with Landlord the Security Deposit to be retained by Landlord as cash security
for the faithful performance and observance by Tenant of the provisions of this
lease. Tenant shall not be entitled to any interest whatever on the Security
Deposit. Landlord shall have the right to commingle the Security Deposit with
its other funds. Landlord may use the whole or any part of the Security Deposit
for the payment of any amount as to which Tenant is in default hereunder or to
compensate Landlord for any loss or damage it may suffer by reason of Tenant's
default under this lease. If Landlord uses all or any portion of the Security
Deposit as herein provided, within 10 days after written demand therefor, Tenant
shall pay Landlord cash in amount equal to that portion of the Security Deposit
used by Landlord. If Tenant shall comply fully and faithfully with all of the
provisions of this lease, the Security Deposit shall be returned to Tenant aftr
the Expiration Date and surrender of the Premises to Landlord.

      IN WITNESS WHEREOF, and in consideration of the mutual entry into this
lease and for other good and valuable consideration, and intending to be legally
bound, Landlord and Tenant have executed this lease.

      Date signed:              Landlord:

                                LIBERTY PROPERTY LIMITED PARTNERSHIP

        5/12/99                 By: Liberty Property Trust, Sole General Partner
     --------------------


                                     By: /s/ John S. Gattuso
                                        ------------------------------------
                                         Name: John S. Gattuso
                                         Title: Senior Vice President



      Date signed:              Tenant

        May 12, 1999
     --------------------       --------------------------------------------

      Attest:

                                By:  /s/ K E Hendrickson
     --------------------          -----------------------------------------
      Name:                          Name: K E Hendrickson
      Title:                         Title: CEO Ancor Communications


                                       11
<PAGE>

                                      RIDER

          This Rider is attached to and made a part of that certain Lease dated
of even date herewith by and between LIBERTY PROPERTY LIMITED PARTNERSHIP, a
Pennsylvania limited partnership, as Landlord, and ANCOR COMMUNICATIONS,
INCORPORATED, a Minnesota corporation, as Tenant. In the event of any conflict
between the terms of this Rider and the terms of the Lease to which this Rider
is attached, the terms of this Rider shall control.



29.  Tenant Improvements.

     (a) Defined Terms. The date set forth in Section I (c)(i) is defined as the
"COMPLETION DATE" and the "COMMENCEMENT DATE" is the date set forth in
subsection (d) below.

     (b) Completion by Landlord. Landlord shall complete the Premises in
accordance with the plans and specifications attached hereto as Exhibit "E'.
Landlord shall use all reasonable efforts to cause the Premises to be
substantially completed ready for use and occupancy by Tenant on or before the
Completion Date, subject to extension for delays due to any cause beyond the
reasonable control of Landlord or Landlord's contractors or suppliers. All
construction shall be done in a good and workmanlike manner and shall comply at
the time of completion with all applicable laws and requirements of the
governmental authorities having jurisdiction. Landlord agrees to complete such
construction at Tenant's sole expense equal to the aggregate of all costs,
expenses and fees incurred by or on behalf of Landlord in connection therewith
(the "Tenant's Cost"), including without limitation (i) architectural,
engineering and design costs, (ii) the cost charged to Landlord by Landlord's
general contractor and all subcontractors for performing such construction, and
(iii) the cost to Landlord of performing directly any portion of such
construction. Landlord agrees to credit Tenant with an allowance equal to the
lesser of the Tenant's Cost or One Hundred Thousand Dollars ($1 00,000) (the
"Tenant Allowance"). Tenant agrees to pay to Landlord, within ten (10) days of
being billed therefor, the excess (if any) of the Tenant's Cost above the Tenant
Allowance.


     (c) Acceptance of Premises. Section 3 of the lease is deleted and restated
as follows:

     "Tenant has examined and knows the condition of the Property, the zoning,
     streets, sidewalks, parking areas, curbs and access ways adjoining it,
     visible easements, any surface conditions and the present uses, and Tenant
     accepts them in the condition in which they now are, without relying on any
     representation, covenant or warranty by Landlord, except as to the work to
     be performed by Landlord pursuant to subsection (b) above and except as
     otherwise provided herein. Landlord represents and warrants that the
     Property as of the date hereof is zoned Industrial. Tenant's occupancy of
     the Premises shall constitute Tenant's


                                       R-1
<PAGE>

     acceptance of such work by Landlord. Tenant and its agents shall have the
     right, at Tenant's own risk, expense and responsibility, at all reasonable
     times prior to the Commencement Date, to enter the Premises for the purpose
     of taking measurements and installing its furnishings and equipment,
     provided that Tenant does not interfere with or delay the work to be
     performed by Landlord, Tenant uses contractors and workers compatible with
     the contractors and workers engaged by Landlord, and Tenant obtains
     Landlord's prior written consent."


     (d) Term. Section 5 of the lease is deleted and restated as follows:

     "The Term of this lease shall commence on the later of (i) October 1, 1999
     or (ii) the date that is 14 days following the date of the substantial
     completion by Landlord of the improvements described in subsection (b)
     above (the "COMMENCEMENT DATE") and shall end at 11:59 p.m. on the last day
     of the Term (the "EXPIRATION DATE"), without the necessity for notice from
     either party, unless sooner terminated in accordance with the terms hereof;
     however, if the date of substantial completion is delayed by Tenant, the
     Term shall commence as if the Premises were substantially complete on the
     Completion Date, as extended for reasons other than those caused by Tenant.
     At Landlord's request, Tenant shall confirm the Commencement Date and the
     Expiration Date by executing a lease commencement certificate in the form
     attached as Exhibit "'B".


     (e) Early Access. Tenant shall at all reasonable times from the date of
substantial completion of the improvements described in subsection (b) above to
the Commencement Date, have access to the Premises, at Tenant's own risk,
expense and responsibility, for purposes of installing Tenant's furniture, trade
fixtures and equipment and for any other purposes permitted under this lease. In
connection with such access prior to the Commencement Date, Tenant shall abide
by the terms and conditions of this lease including carrying the insurance
specified by the lease, as if the term of this lease had already commenced,
except that Tenant shall have no obligation to pay the Minimum Annual Rent or
Annual Operating Expenses until the Commencement Date. Tenant shall pay the
charges for all utilities furnished to the Premises during Tenant's early-access
period, as reasonably estimated by Landlord.


     30. Extension Option. Provided that there then exists no event of material
default by Tenant under this Lease beyond any applicable notice and cure period,
Tenant shall have the right and option to extend the Term of this Lease for one
(1) additional extension term of five (5) years. Such option must be exercised,
if at all, by giving Landlord prior written notice, at least 180 days in advance
of the expiration date of the then current lease Term, of Tenant's election to
extend the lease Term; it being agreed that time is of the essence and that this
option is personal to Tenant and is non-transferable to any assignee or
sublessee (regardless of whether any such assignment or sublease was made with
or without Landlord's consent) or other party. Each extension Term shall be
under the same terms and conditions as provided in the Lease except as follows:


                                       R-2
<PAGE>

     (a)  there shall be no further options to extend the term;

     (b)  Tenant shall accept the Premises in their "as is" condition, without
          any obligation on the part of Landlord to provide any tenant
          improvements or tenant improvement allowance; and

     (c)  the Minimum Annual Rent for the extension term shall be negotiated
          between Landlord and Tenant as follows:

          If Tenant wishes to preserve its rights to exercise its extension
          option, Tenant must give Landlord, not less than 240 days in advance
          of the expiration date of the then current lease Term, a written
          request for Landlord's determination of the then fair market Minimum
          Annual Rent for such extension term, time being of the essence.
          Landlord shall provide Tenant written notice of Landlord's good faith
          determination of the fair market Minimum Annual Rent (taking into
          consideration market rates without tenant improvement allowances and
          other tenant inducements if none are offered by Landlord) not more
          than 20 days following receipt of Tenant's timely request, provided,
          however, in no event shall the Annual Minimum Rent be less than the
          scheduled Annual Minimum Rent payable for the last lease year of the
          initial term. If Tenant disputes Landlord's determination and wishes
          to negotiate the Annual Minimum Rent, Tenant shall so notice Landlord.
          Tenant shall have until the date that is 180 days in advance of the
          expiration date of the then current lease Term in which to reach a
          written agreement with Landlord regarding the Annual Minimum Rent for
          the applicable extension term. If Tenant timely exercises its option
          absent such written agreement with Landlord, the Annual Minimum Rent
          shall be that stipulated in Landlord's original determination notice.
          If Tenant timely exercises its option after reaching express written
          agreement with Landlord as to Annual Minimum Rent and any other terms
          or conditions applicable to the option term, the Annual Minimum Rent
          and the other terms and conditions for the applicable extension term
          shall be as stated in such agreement. If Tenant fails to timely
          exercise its extension option, such option shall be deemed void and of
          no force or effect.

     Upon the timely exercise of an extension option, at the request of either
party the other party hereto will enter into an appropriate amendment to the
Lease incorporating the terms of the Lease extension.

31. Compliance. Any provision to the contrary in Section 4(b) notwithstanding,
Tenant shall not be obligated for the performance or payment of any alterations
or improvements in the Premises or Building in order to comply with Laws and
Requirements unless (i) the need for compliance arises out of Tenant's unique or
peculiar use or occupancy of the


                                       R-3
<PAGE>

Premises (in contrast to Laws and Requirements that would apply to an office
user generally), (ii) the need for compliance is triggered by alterations or
improvements in and to the Premises made by Tenant, or (iii) Landlord is
expressly permitted to include the cost thereof in operating expenses under the
provisions of Section 7 of this Lease.

32. Operating Expenses. Section 7(a) notwithstanding, the following categories
of costs and expenses shall be excluded from Operating Expenses:


     (a)  Repairs or other work occasioned by fire, windstorm or other casualty
          or condemnation, except that Landlord shall be able to include any
          reasonable deductible paid with respect thereto.

     (b)  Leasing commissions, attorney's fees, costs and disbursements and
          other expenses incurred in connection with negotiations or disputes
          with tenants, other occupants, or prospective tenants or other
          occupants.

     (c)  Costs incurred in renovation or otherwise improving or decorating,
          painting or redecorating space for tenants or other occupants or
          vacant leaseable space.

     (d)  Expenses in connection with services or other benefits of a type which
          are not provided Tenant but which are provided to another tenant or
          occupant.

     (e)  The cost of alterations or improvements which under generally accepted
          principles are properly classified as capital expenditures except to
          the extent expressly permitted under Section 7 of the lease; for
          purposes of calculating Operating Expenses, the cost of such capital
          expenditures shall be amortized over the useful life thereof and
          Operating Expenses shall include only that portion of the amortized
          cost of such capital improvement or expenditure, including reasonable
          interest and financing charges thereon, which falls within the Term,
          including any extension.


     (f)  Depreciation and amortization (except as expressly permitted under
          this lease).

     (g)  Costs (including penalties, fines and legal expenses) incurred due to
          violation by Landlord of the terms and conditions of this lease or any
          other lease.

     (h)  Fees or other compensation paid to subsidiaries or affiliates of
          Landlord for services on or to the Building, to the extend that the
          costs of such services exceed competitive costs of such services were
          they not so rendered by a subsidiary or affiliate.

     (i)  Interest on debt or amortization payments on any mortgage(s), and
          rental under any ground or underlying lease(s).

                                       R-4
<PAGE>

     (j)  Landlord's general partnership or corporate overhead and general
          administrative expenses.

     (k)  Rentals and other related expenses incurred in leasing air
          conditioning systems, elevators, or other equipment ordinarily
          considered to be of a capital nature, except equipment which is used
          in providing janitorial services and which is not fixed to the
          Building.

     (l)  All items and services for which Tenant reimburses Landlord outside of
          operating expense payments or pays third persons, to the extent of the
          reimbursement or payment.

     (k)  Advertising and promotional expenditures.

     (l)  Any costs, fines, penalties, legal fees or costs of litigation
          incurred due to violations by Landlord, its employees, agents
          contractors or assigns, of any governmental rule or authority.
          Interest or penalties due to late payments of taxes, utility bills and
          other costs.

     (m)  Wages, salaries or other compensation paid to any executive employees
          above the grade of building manager.

33. Repairs and Maintenance.

     33.1 The words "interior of the" are hereby added before "Premises" and
          after "maintain the" in line 2 of Section 7(d).

     33.2 Landlord shall maintain and repair, the Property in a manner
          consistent with the, standards prevailing in comparable buildings in
          the Minneapolis/St. Paul metropolitan area.

34. Alterations. The word "reasonable" is hereby added before "costs" in the
second sentence of Section 9(b).

35. Landlord's Right of Entry. The words "12 months" in line 3 of Section 11 are
hereby amended to read "6 months".

36. Damage by Fire or other Casualty. In Section 12(a), the last sentence is
hereby amended and restated as follows: "Further, if a casualty affecting the
Premises or Tenant's use and occupancy thereof occurs during the last 12 months
of the Term or any extension thereof, Landlord or Tenant may cancel this Lease
effective as of the date of the casualty by giving written notice to the other
not more than 30 days after the date of the casualty; the foregoing
notwithstanding, Landlord shall not terminate this Lease if Tenant has the right
to extend the Term for at least 3 more years and does so within 30 days after
the date of the casualty."

37. Taking, The words "Minimum Annual" before "Rent" in line 5 of Section 13(b)
are hereby deleted. Section 13(d) (Temporary Taking) is hereby deleted.


                                       R-5
<PAGE>

38. Indemnification of Tenant. Subject to Sections 7(c)(iii) and 16, Landlord
will protect, indemnify and hold harmless Tenant and its Agents from and against
any and all claims, actions, damages, liability and expense (including fees of
attorneys, investigators and experts) in connection with loss of life, personal
injury or damage to property caused to any person in or about the Premises
occasioned wholly or in part by the negligence of Landlord or its Agents, except
to the extent such loss, injury or damage was caused by the negligence of Tenant
or its Agents. In case any action or proceeding is brought against Tenant and/or
its Agents by reason of the foregoing, Landlord, at its expense, shall resist
and defend such action or proceeding, or cause the same to be resisted and
defended by counsel (reasonably acceptable to Tenant and its Agents) designated
by the insurer whose policy covers such occurrence or by counsel designated by
Landlord and approved by Tenant and its Agents. Landlord's obligations pursuant
to this Section shall survive the expiration or termination of this lease.

39. Surrender. The words "and all fixtures and equipment servicing the Building"
in the third line of Section 21(a) are hereby deleted. The word "double" in line
3 of Section 21(c) is hereby amended to read "one hundred fifty percent (150%)
of".

40. Curing Tenant's Defaults. The words "5 days" is hereby added before
"written notice" in line 3 of Section 22. The parenthetical "(which demand shall
include reasonable documents evidencing Landlord's costs)" is hereby inserted
after "demand" in line 3 of Section 22.

41. Defaults - Remedies.

     41.1 Section 23(a)(iii) [abandonment provision] is hereby deleted.

     41.2 In Section 23(b)(ii) the words "breaking open locked doors if
          necessary" in line. I are hereby deleted and replaced with the words
          "by process of law", and the words "or otherwise" in line 2 are hereby
          deleted.

     41.3 Section 23(b)(iii): any accelerated rent will be discounted to present
          value using a discount rate equal to the annual yield on U.S. Treasury
          Bonds with a remaining term equal to the period from the date of
          acceleration through the scheduled date of expiration of the then
          current term of the lease. In the event of an acceleration of rent
          under Section 23(b)(iii), Landlord shall timely refund to Tenant
          accelerated rent paid by Tenant in an amount equal to any rental
          payments for all or any portion of the Premises subsequently received
          by Landlord attributable to the time period for which the accelerated
          rent was paid, less the reasonable, documented costs incurred by
          Landlord in reletting the Premises or any applicable portion thereof.

     41.4 Section 23(b)(iv) is hereby amended and restated as follows:

                    "(iv) To terminate this lease and the Term without any right
               on the part of Tenant, other than as provided under applicable
               state statute, to save the forfeiture by payment of any


                                       R-6
<PAGE>

               sum due or by other performance of any condition, term or
               covenant broken."

     41.5 Section 23(c)(iv) is hereby amended and restated as follows:

                    "(iv) Tenant and Landlord agree that any notice given by
               Landlord or Tenant pursuant to this Section which is served in
               compliance with Section 27 shall be adequate notice for the
               purpose of the noticing party's exercise of any available
               remedies."

     41.6 Section 23(d) is hereby amended and restated as follows:

               "(d) Non-Waiver, Non-Exclusive. No waiver by Landlord or Tenant
               of any breach by the other shall be a waiver of any subsequent
               breach, nor shall any forbearance by Landlord or Tenant to seek a
               remedy for any breach by the other be a waiver by Landlord or
               Tenant of any rights and remedies with respect to such or any
               subsequent breach. Efforts by Landlord or Tenant to mitigate the
               damages caused by the other's default shall not constitute a
               waiver of Landlord's or Tenant's right to recover damages
               hereunder. Unless this lease expressly so provides to the
               contrary, no right or remedy herein conferred upon or reserved to
               Landlord or Tenant is intended to be exclusive of any other right
               or remedy provided herein or by law, but each shall be cumulative
               and in addition to every other right or remedy given herein or
               now or hereafter existing at law or in equity. No payment by
               Tenant or receipt or acceptance by Landlord of a lesser amount
               than the total amount due Landlord under this lease shall be
               deemed to be other than on account, nor shall any endorsement or
               statement on any check or payment be deemed an accord and
               satisfaction, and Landlord may accept such check or payment
               without prejudice to Landlord's right to recover the balance of
               Rent due, or Landlord's right to pursue any other available
               remedy."

42. Landlord's Authority. Landlord is a duly organized limited partnership under
the laws of the State of Pennsylvania and has taken all partnership action
necessary to carry out the transaction contemplated herein, so that when
executed, this lease constitutes a valid and binding obligation enforceable in
accordance with its terms.

43. Interest. Section 26(d) is hereby amended and restated as follows:

          "(d) Interest. Wherever interest is required to be paid hereunder,
          such interest shall be at the highest rate permitted under law, but
          not in excess of the "prime rate" plus four percent (4%). "Prime rate"
          herein means the rate of interest per annum from time to time
          published in The Wall Street Journal (or comparable financial
          publication if The Wall Street Journal ceases to be published or
          ceases to publish a prime rate) as the "High


                                       R-7
<PAGE>

          Prime Rate", or the "Prime Rate" if only one "Prime Rate" is
          published, as the same may fluctuate from time to time."

44. Default by Landlord. If Landlord defaults under the terms of this lease,
Landlord shall have all reasonable and adequate time in which to cure the same
after written notice of such default is received by Landlord from Tenant. If
Landlord fails to cure the same, Tenant shall, subject to Section 25 (entitled
"Liability of Landlord") of the lease, have all rights and remedies available to
Tenant under law or at equity.

45. HVAC. On or before the Commencement Date, Landlord will provide Tenant an
inspection certificate issued by a qualified inspector indicating that the HVAC
system is in proper working order.

46. Audit of Landlord's Operating Expense Records. Tenant shall be entitled at
any reasonable time during regular business hours, but no more than once in each
calendar year, after giving to Landlord at least five (5) business days prior
written notice, to inspect in Landlord's business office all Landlord's records
necessary to satisfy itself that all charges have been correctly allocated to
Tenant, for either or both of the two (2) calendar years immediately preceding
the year during which such notice is given, and to obtain an audit thereof by an
independent certified public accountant (selected by Tenant with Landlord's
written consent, which shall not be withheld unreasonably) to determine the
accuracy of Landlord's certification of the amount of additional rent charged
Tenant. If it is determined that Tenant's liability for additional rent for
either such calendar year is less than ninety-five percent (95%) of that amount
which Landlord previously certified to Tenant for such calendar year, Landlord
shall pay to Tenant the cost of such audit (provided, however, that Landlord
shall not be required to pay the cost of any audit based on a contingency fee or
percentage of the amount recovered for Tenant) and regardless of such
percentage. Landlord shall refund promptly to Tenant the amount of the
additional rent paid by Tenant for such calendar year which exceeds the amount
for which Tenant actually is liable, as determined following such audit. If it
is determined that Tenant's liability for additional rent for either such
calendar year is more than the amount which Landlord previously certified to
Tenant for such calendar year, Tenant shall promptly pay to Landlord (net of the
cost to Tenant of the audit) the amount of the additional rent underpaid by
Tenant, as determined following such audit. Except as provided above, Tenant
shall bear the total cost of any such audit. Tenant shall keep, and shall cause
Tenant's auditor to keep, the results of such audit confidential.

47. Right of First Offer. In the event any space in the Building becomes
available for lease at any time during the Term of this Lease (the "Offer
Space"), and the party, if any, in possession of or with rights to such Offer
Space does not desire to remain in possession or exercise such rights, Landlord
shall give Tenant written notice of the availability of such Offer Space and of
the proposed Minimum Annual Rent for such Offer Space (which shall be the then
prevailing rate for comparable space in the Building as determined by Landlord),
and Tenant shall have the right, at its option, to lease such Offer Space
provided (a) Tenant delivers to Landlord written notice exercising its right to
lease such Offer Space within 10 days of receipt of Landlord's notice of
availability of such Offer Space, and (b) Tenant is not in default in any
material respect under this Lease at the time Tenant exercises its right to
lease such Offer Space and at the time Tenant is to take


                                       R-8
<PAGE>

possession of such Offer Space. If Tenant fails to exercise timely its right to
lease such Offer Space with respect to a particular notice of availability given
by Landlord, Tenant will have no further right to lease such Offer Space, and
this right of first offer shall terminate with respect to such Offer Space. If
Tenant elects to exercise its right to lease such Offer Space, the terms,
conditions and covenants applicable to such Offer Space shall be as set forth in
this Lease, except that the Minimum Annual Rent regarding such space shall be at
the then prevailing rate for comparable space in the Building as determined by
Landlord and as stated in the offer notice, and the Offer Space shall be
delivered to Tenant in an "as is" condition. The commencement date for the lease
covering such space shall be the date following the exercise of such option on
which such space is first made available to Tenant. If Tenant exercises its
right to lease such space, Landlord and Tenant shall execute and deliver an
appropriate amendment to this Lease regarding the lease of such space. The
foregoing notwithstanding, Tenant shall have no right to lease any Offer Space
unless at least two (2) full years remain in the Term hereof or unless Tenant
has the right to extend the Term and does so in connection with its lease of the
Offer Space. The rights provided Tenant in this Section shall be subject to any
prior rights of any existing tenant of the Building.


                                       R-9
<PAGE>

Landlord and Tenant have executed this Rider (consisting of Sections 29 through
47) as of the last date indicated below.

                                Landlord:

Date signed:  5/12  , 1999      LIBERTY PROPERTY LIMITED PARTNERSHIP
            --------
                                By: Liberty Property Trust, Sole General Partner

                                    By: /s/ John Gattuso
                                        -----------------------------------
                                        John Gattuso, Senior Vice President


                                Tenant:

Date signed:  May 12  , 1999    ANCOR COMMUNICATIONS, INCORPORATED
             ---------

                                By:  /s/ K E Hendrickson
                                     -----------------------------------

                                Its: CEO
                                     -----------------------------------



                                       R-10
<PAGE>

                                   EXHIBIT "A"



                             [space layout drawing]
<PAGE>

                                   EXHIBIT "B"
                         LEASE COMMENCEMENT CERTIFICATE

     The undersigned, as duly authorized officers and/or representatives of
LIBERTY PROPERTY LIMITED PARTNERSHIP ("Landlord") and ________________________
("Tenant"), hereby agree as follows with respect to the Lease Agreement (the
"Lease") between them for premises located at ________
_______________________________ (the "Premises"):

         1.  Date of Lease:     ____________________________  , 19__

         2.  Commencement Date: ____________________________  , 19__

         3.  Expiration Date:   ____________________________  , 19__

         4.  Rent and operating expenses due on or before the Commencement Date
             for the period from the Commencement Date until the first day of
             the next calendar month (Not applicable if the Commencement Date is
             the first day of the calendar month):

                  Apportioned Minimum Rent:        $______________________
                  Apportioned Operating Expenses:  $______________________
                  TOTAL                            $______________________

             Thereafter regular monthly payments due in the following amounts
until adjusted in accordance with the Lease:

                  Monthly Rent Installment:        $______________________
                  Monthly Operating Payment        $______________________
                  TOTAL MONTHLY PAYMENT:           $______________________

         5.  Tenant certifies that, as of the date hereof, (a) the Lease in full
             force and effect and has not been amended. (b) Tenant has no
             offsets or defenses against any provision of the Lease and (c)
             Landlord has substantially completed any improvements to be
             performed by Landlord in accordance with the Lease, excepting the
             Punch List items set forth on the Schedule attached hereto and
             initialed by Landlord and Tenant, if any.

         IN WITNESS WHEREOF, Landlord and Tenant, intending to be legally bound,
have executed this Certificate as of ________________, 19__.

                              LANDLORD:

                              LIBERTY PROPERTY LIMITED PARTNERSHIP

                              By: Liberty Property Trust, Sole General Partner

                                  By: ______________________
                                      Name:
                                      Title:

                              TENANT:

Witness/Attest:               ____________________________________________

______________________        By: ________________________________________
                                  Name:
                                  Title:
<PAGE>

                                   EXHIBIT "C"


                                 BUILDING RULES


      1. As stated in the lease. Tenant shall not use the Premises as a "place
of public acconunodation" as defined in the ,Americans with Disabilities Act of
1990, which identifies the following categories into one or more of which a
business must fall to be a "place of public accommodation":

          a. Places of lodging (examples: hotel, motel)
          b. Establishments serving food or drink (examples: bar, restaurant)
          c. Places of exhibition or entertainment (examples: motion picture
             house, theater, stadium, concert hall)
          d. Places of public gathering (examples: auditorium convention
             center, lecture hall)
          e. Sales or rental establishments (examples: bakery, grocery store,
             hardware store, shopping center)
          f. Service establishments (examples: bank, laundromat barber shop,
             funeral parlor, hospital, gas station, business offices such as
             lawyer, accountant, healthcare provider or insurance office)
          g. Stations used for specified public transportation (examples: bus
             terminal, depot)
          h. Places of public display or collection (examples: museum library,
             gallery)
          i. Places of recreation (examples: park. zoo, amusement park)
          j. Places of education (examples: nursery, elementary, secondary,
             private or other undergraduate or postgraduate school)
          k. Social service center establishments (examples: daycare center,
             senior citizen center, homeless shelter, food bank, adoption
             agency)
          l. Places of exercise or recreation (examples: gym, health spa,
             bovaing alley, golf course)

      2. Any sidewalks, lobbies, passages and stairways shall not be obstructed
or used by Tenant for any purpose other than ingress and egress from and to the
Premises. Landlord shall in all cases retain the right to control or prevent
access by all persons whose presence, in the judgment of Landlord, shall be
prejudicial to the safety, peace or character of the Property.

      3. The toilet rooms, toilets, urinals, sinks. faucets, plumbing or other
service apparatus of any kind shall not be used for any purposes other than
those for which they were installed, and no sweepings, rubbish, rags, ashes,
chemicals or other refuse or injurious substances shall be placed therein or
used in connection therewith or left in any lobbies, passages, elevators or
stairways.

      4 Tenant shall comply with all safety, fire protection and evacuation
procedures and regulations established by Landlord or any governmental agency.
No person shall go on the roof without Landlord's permission.

      5. Skylights, windows, doors and transoms shall not be covered or
obstructed by Tenant, and Tenant shall not install any window covering which
would affect the exterior appearance of the Building, except as approved in
writing by Landlord. Tenant shall not remove, without Landlords prior written
consent, any shades, blinds or curtains in the Premises.

      6. Without Landlords prior written consent, Tenant shall not hang,
install, mount, suspend or attach anything from or to any sprinkler, plumbing
utility or other lines. If Tenant hangs, installs, mounts, suspends or attaches
anything from or to any doors. windows, walls, floors or ceilings, Tenant shall
spackle and sand all holes and repair any damage caused thereby or by the
removal thereof at or prior to the expiration or termination of the lease. If
Tenant elects to seal the floor, Tenant shall seal the entire unfinished floor
area within the Premises. If Tenant elects to paint all or any portion of the
Premises, Tenant, prior to the termination of the lease, shall restore all or
such portion(s) of. the Premises to the painted or unpainted condition thereof
as of the Commencement Date.

      7. Tenant shall not change any locks nor place additional locks upon any
doors and shall surrender all keys and passes at the end of the Term.

      8. Tenant shall not use nor keep in the Building any matter having an
offensive odor, nor explosive or highly flammable material. nor shall any
animals other than seeing eye dop in the company of their masters be brought
into or kept in or about the Premises.


                                       C-1
<PAGE>

      9. If Tenant desires to introduce electrical, signalling. telegraphic,
telephonic, protective alarm or other wires, apparatus or devices, Landlord
shall direct where and how the same are to be placed, and except as so directed,
no installation boring or cutting shall be permitted. Landlord shall have the
right to prevent and to cut off the transmission of excessive or dangerous
current of electricity or annoyances into or through the Building or the
Premises and to require the changing of wiring connections or layout at Tenant's
expense, to the extent that Landlord may deem necessary, and further to require
compliance with such reasonable rules as Landlord may establish relating
thereto, and in the event of non-compliance with the requirements or rules,
Landlord shall have the right immediately to cut wiring or to do what it
considers necessary to remove the danger, annoyance or electrical interference
with apparatus in any part of the Building. All wires installed by Tenant must
be clearly tagged at the distributing boards and junction boxes and elsewhere
where required by Landlord, with the number of the office to which said wires
lead, and the purpose for which the wires respectively are used, together with
the name of the concern, if any, operating same.

      10. Tenant shall not place weights anywhere beyond the safe carrying
capacity of the Building,

      11. The use of rooms as sleeping quarters is strictly prohibited at all
times.

      12. Tenant shall have the right, at Tenant's sole risk and responsibility,
to use its proportional share of the parking spaces at the Property as
reasonably determined by Landlord. Tenant shall comply with all parking
regulations promulgated by Landlord from time to time for the orderly use of the
vehicle parking area, including without limitation the following; Parking shall
be limited to automobiles. passenger or equivalent vans. motorcycles, light four
wheel pickup trucks and (in designated areas) bicycles. No vehicles shall be
left in the parking lot overnight. Parked vehicles shall not be used for vending
or any other business or other activity while parked in the parking areas.
Vehicles shall be parked only in striped parking spaces, except for loading and
unloading, which shall occur solely in zones marked for such purpose. and be so
conducted as to not unreasonably interfere with traffic flow within the Property
or with loading and unloading areas of other tenants. Employee and tenant
vehicles shall not be parked in spaces marked for visitor parking or other
specific use. All vehicles entering or parking in the parking areas shall do so
at owner's sole risk, and Landlord assumes no responsibility for any damage,
destruction, vandalism or theft. Tenant shall cooperate with Landlord in any
measures implemented by Landlord to control abuse of the parking areas,
including without limitation access control programs, tenant and guest vehicle
identification programs, and validated parking programs, provided that no such
validated parking programs shall result in Tenant being charged for spaces to
which it has a right to free use under its lease. Each vehicle owner shall
promptly respond to any sounding vehicle alarm or ham and failure to do so may
result in temporary or permanent exclusion of such vehicle from the parking
areas. Any vehicle which violates the parking regulations may be cited, towed at
the expense of the owner, temporarily or permanently excluded from the parking
areas, or subject to other lawful consequence.

      13. If Landlord designates the Building as a non-smoking building and
provides outdoor smoking area(s), Tenant and its Agents shall not smoke in the
Building.

      14. If at Tenant's request, Landlord consents to Tenant having a dumpster
at the Property, Tenant shall locate the dumpster in the area designated by
Landlord and shall keep and maintain the dumpster clean and painted with lids
and doors in good working order and, at Landlords request, locked.

      15. Tenant shall provide Landlord with a written identification of any
vendors engaged by Tenant to perform services for Tenant at the Premises
(examples: cleaners, security guards/monitors, trash haulers, telecommunications
installers/maintenance).

      16. Tenant shall cause all of Tenant's Agents to comply with these
Building Rules.

      17. Landlord reserves the right to rescind, suspend or modify any rules or
regulations and to make such other rules and regulations as, in Landlords
reasonable judgment, may from time to time be needed for the safety, care,
maintenance. operation and cleanliness of the Property. Notice of any action by
Landlord referred to in this paragraph, given to Tenant, shall have the same
force and effect as if originally made a part of the foregoing lease . New rules
or regulations will not, however, be unreasonably inconsistent with the proper
and rightful enjoyment of the Premises by Tenant under the lease.

       18. These Building Rules are not intended to give Tenant any rights or
claims in the event that Landlord does not enforce any of them against any other
tenants or if Landlord does not have the right to enforce them against any other
tenants and such non enforcement will not constitute a waiver as to Tenant.

       19. Tenant shall be deemed to have read these Building Rules and to have
 agreed to abide by them as a condition to Tenant's occupancy of the Premises.


                                       C-2
<PAGE>

                                   EXHIBIT "D"
                           TENANT ESTOPPEL CERTIFICATE
                           ---------------------------

      Please refer to the documents described in Schedule I hereto, (the "Lease
Documents') including the "Lease " therein described ail defined terms in this
Certificate shall have the same meanings as set forth in the Lease unless
otherwise expressly set forth herein. The undersigned Tenant hereby certifies
that it is the tenant under the Lease. Tenant hereby further acknowledges that i
has been advised that the Lease may be collaterally assigned in connection with
a proposed financing secured by the Property and/or may be assigned in
connection with a sale of the Property and certifies both to Landlord and to any
and all prospective mortgagees and purchasers of the Property, including any
trustee on behalf of any holders of notes or other similar instruments, any
holders from time to time of such notes or other instruments, and their
respective successors and assigns (the "Mortgagees") that as of the date hereof:

      1. The information set forth in attached Schedule 1 is true and correct.

      2. Tenant is in occupancy of the Premises and the Lease is in full force
and effect, and, except by such writings as are identified on Schedule 1, has
not been modified, assigned, supplemented or amended since its original
execution, nor are there an other agreements between Landlord and Tenant
concerning the Premises, whether oral or written.

      3. All conditions and agreements under the Lease to be satisfied or
performed by Landlord have been satisfied and performed.

      4. Tenant is not in default under the Lease Documents, Tenant has not
received any notice of default under the Leas, Documents, and. to Tenant's
knowledge, there are no events which have occurred that, with the giving of
notice and/or the passage of time. would result in a default by Tenant under the
Lease Documents.

      5. Tenant has not paid any Rent due under the Lease more than 30 days in
advance of the date due under the Lease an, Tenant has no rights of setoff,
counterclaim, concession or other rights of diminution of any Rent due and
payable under the Lease except as set forth in Schedule 1.

      6. To Tenant's knowledge, there are no uncured defaults on the part of
Landlord under the Lease Documents, Tenant has not sent any notice of default
under the Lease Documents to Landlord, and there are no events which have
occurred that, with the giving of notice and/or the passage of time, would
result in a default by Landlord thereunder, and that at the present time Tenant
has no claim against Landlord under the Lease Documents.

      7. Except as expressly set forth in Part G of Schedule 1, there are no
provisions for any, and Tenant has no. options with respect to the Premises or
all or any portion of the Property.

      8. Except as set forth on Part M of Schedule 1, no action, voluntary or
involuntary, is pending against Tenant under federal or state bankruptcy or
insolvency law.

      9. The undersigned has the authority to execute and deliver this
Certificate on behalf of Tenant and acknowledges that a \4ortgagees will rely
upon this Certificate in purchasing the Property or extending credit to Landlord
or its successors in interest.

      10. This Certi6cate shall be binding upon the successors, assigns and
representatives of Tenant and any party claiming through or under Tenant and
shall inure to the benefit of all Mortgagees.

      IN WITNESS WHEREOF, Tenant has executed this Certificate this ___ day of
________, 19__.


                                             ---------------------------------
                                                 Name of Tenant

                                                 By:
                                                    --------------------------

                                                 Title:
                                                       -----------------------


                                       D-1
<PAGE>

                    SCHEDULE 1 TO TENANT ESTOPPEL CERTIFICATE

                 Lease Documents, Lease Terms and Current Status
                 -----------------------------------------------



A. Date of Lease:

B. Parties

   1.  Landlord:

   2. Tenant d/b/a:

C. Premises known as:

D. Modifications, Assignments, Supplements or Amendments to Lease:



E. Commencement Date:

F. Expiration of Current Term:

G. Options:

H. Security Deposit Paid to Landlord:  $

I. Current Fixed Minimum Rent (Annualized):  $

J. Current Additional Rent (and if applicable, Percentage Rent) (Annualized): $

K. Current Total Rent:  $

L. Square Feet Demised:

M. Tenant's Bankruptcy or other insolvency Actions:




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