<PAGE>

                                                                   EXHIBIT 10.15

               THE GREENSPOINT TECHNOLOGY CENTER, HOUSTON, TEXAS
                                   NET LEASE

                            BASIC LEASE INFORMATION
                            -----------------------


Date:  December 21, 1999
----

Landlord:  THE TRUSTEES UNDER THE WILL AND OF THE ESTATE OF JAMES CAMPBELL,
--------
           DECEASED, ACTING IN THEIR FIDUCIARY AND NOT IN THEIR INDIVIDUAL
           CAPACITIES

Tenant:  EBASEONE CORPORATION
------

                                              Lease Reference
                                              ---------------

Premises and "Project" address:               article I
------------------------------
     12095 I-45 North
     Houston, Texas 77060

Approximate area of Premises:                 article I
----------------------------
     18,460 square feet

Approximate area of Project:                  article I
---------------------------
     299,703 square feet

"Commencement Date":                          article I
-------------------
     March 1, 2000

"Termination Date":                           article I
------------------
February 28, 2010

"Base Rent":                                  article II
-----------
     $21,536.67 March, 2000-February, 2005
     24,613.33 March, 2005-February, 2010

Initial Monthly Payment:                      article II
-----------------------

             Base Rent:            $21,536.67
    Operating Expenses:            $ 3,852.27
                                   ----------
                 TOTAL:            $25,388.94

"Tenant's Proportionate Share":               article I
------------------------------
     6.16%

"Use":                                        article XIII
-----
     executive and general office use, and
     the installation, operation, and
     maintenance of equipment and facilities
     in connection with Tenant's
     telecommunications business,
     including, but not limited to, a switch
     system


"Security Deposit":                           article II
------------------
     $25,388.94

 "Tenant's Address for Notices":              article XXIV
-------------------------------
     David Tippett, managing director
     ebaseOne Corporation
     6060 Richmond, suite 190
     Houston, Texas 77057
     (713) 781-5535 facsimile

     with a photocopy to:
     --------------------
     ebaseOne Corporation
     12095 I-45 North
     Houston, Texas 77060
     _____________facsimile

"Landlord's Address for Notices":             article XXIV
--------------------------------
     The Estate of James Campbell
     425 California Street, suite 1000
     San Francisco, California 94104-2205
     (415) 291-5720 facsimile
<PAGE>

     attention:  Director, Mainland Operations

Broker:                                        article XXVIII
------
     Trammell Crow Houston, Inc.
     Noble C. Ginther, III
<PAGE>

The articles in the Lease identified in the Lease Reference above are those
provisions where references to particular Basic Lease Information first appear.
All such references incorporate the applicable Basic Lease Information.  In the
event of any conflict between the Basic Lease Information and the Lease, the
Lease shall control.

                               TABLE OF CONTENTS
                               -----------------
<TABLE>
<CAPTION>
                                                                                                page
                                                                                                ----
<S>                                                                                             <C>
Basic Lease Information.......................................................................     i
Table of Contents.............................................................................    ii
Table of Exhibits and Addenda.................................................................    ii
Index to Defined Terms........................................................................    ii
Premises, Term, and Initial Improvements......................................................     1
Base Rent/Security Deposit....................................................................     2
Operating Expenses............................................................................     2
Personal Property Taxes.......................................................................     4
Landlord's Maintenance and Repair Obligations.................................................     4
Tenant's Maintenance and Repair Obligations...................................................     5
Alterations, Additions, Improvements..........................................................     5
Signs.........................................................................................     6
Utilities.....................................................................................     6
Insurance.....................................................................................     6
Casualty Damage...............................................................................     7
Liability/Indemnification/Waiver of Subrogation...............................................     8
Use...........................................................................................     8
Vacation/Restoration/Holding Over.............................................................     9
Assignment and Subletting.....................................................................    10
Condemnation..................................................................................    11
Quiet Enjoyment...............................................................................    11
Events of Default.............................................................................    11
Remedies......................................................................................    12
Landlord Default/Limitation of Liability......................................................    13
Mortgages.....................................................................................    13
Tenant Encumbrances...........................................................................    14
Landlord's Lien...............................................................................    14
Notices.......................................................................................    14
Hazardous Materials...........................................................................    15
Emergency Power...............................................................................    15
Collocation...................................................................................    16
Miscellaneous.................................................................................    16
</TABLE>


                         TABLE OF EXHIBITS AND ADDENDA
                         -----------------------------
<TABLE>
<S>                           <C>
Exhibit "A"..............................................................................Site Plan
Exhibit "B"...........................................................Legal Description of Project
Exhibit "C"....................................................................Tenant Improvements
Exhibit "C-1"...........................................................................Space Plan
Exhibit "D"..................................................................Rules and Regulations
Exhibit "E"..................................................................Environmental Matters
Exhibit "F"..................................................................Option to Extend Term
Exhibit "G"......................Telecommunication Receiver and Transmission Equipment/Use of Roof
</TABLE>

                            INDEX TO DEFINED TERMS
                            ----------------------
<TABLE>
<CAPTION>
Defined Term                                                                                      page
--------------                                                                                    ----
<S>                                                                                               <C>
Additional Rent...............................................................................       2
Address for Notices...........................................................................       i
Base Rent.....................................................................................       i
Claimant......................................................................................      12
Collateral....................................................................................      14
Commencement Date.............................................................................       i
Default Costs.................................................................................      12
Environmental Law.............................................................................      15
Event of Default..............................................................................      11
Hazardous Substances..........................................................................      15
Indemnified Parties...........................................................................       8
Landlord......................................................................................       1
Landlord's Mortgagee..........................................................................      14
Lease.........................................................................................       1
</TABLE>

------------
* No Exhibit C-1 exists with respect to this agreement.


<PAGE>

<TABLE>
<S>                                                                                               <C>
Loss..........................................................................................       8
Mortgage......................................................................................      13
Operating Expenses............................................................................       2
Permitted Conditions..........................................................................      15
Permitted Substances..........................................................................      15
Premises......................................................................................       1
Primary Lease.................................................................................      13
Project.......................................................................................       i
Project's Structure...........................................................................       4
Security Deposit..............................................................................       i
System                                                                                              16
Taking........................................................................................      11
Taxes.........................................................................................       4
Tenant........................................................................................       1
Tenant's Proportionate Share..................................................................       i
Term..........................................................................................       1
Termination Date..............................................................................       i
Transfer......................................................................................      10
Use...........................................................................................       i
Vacation Date.................................................................................       9
</TABLE>

<PAGE>

               THE GREENSPOINT TECHNOLOGY CENTER, HOUSTON, TEXAS
                                   NET LEASE
                                   ---------

     This lease agreement (the "Lease") is entered into by and between THE
TRUSTEES UNDER THE WILL AND OF THE ESTATE OF JAMES CAMPBELL, DECEASED, ACTING IN
THEIR FIDUCIARY AND NOT IN THEIR INDIVIDUAL CAPACITIES ("Landlord") and EBASEONE
CORPORATION, a Delaware corporation ("Tenant").


                 I.  PREMISES, TERM, AND INITIAL IMPROVEMENTS

                                   Premises
                                   --------

     Landlord leases to Tenant, and Tenant leases from Landlord, for the term of
the Lease, at the rental and upon the terms and conditions set forth below, the
space depicted on the site plan attached to the Lease as Exhibit "A" (the
"Premises"), which is part of the Project located on the real property described
on Exhibit "B". Landlord and Tenant stipulate that, as of the date of the Lease,
regardless of minor variations which may result from methods of measuring, the
size of the Premises and the size of the Project as stated in the Basic Lease
Information is correct. Tenant's Proportionate Share shall be appropriately
adjusted if the size of the Premises or the Project changes after commencement
of the Lease.

                                     Term
                                     ----

     The term of the Lease (the "Term"), which shall include all renewals and
extensions of the original term, shall begin on the Commencement Date, and shall
end on the Termination Date (unless extended pursuant to any written renewal or
extension agreement), unless sooner terminated as provided under the terms of
the Lease.
     Landlord shall have the right to unilaterally adjust the Commencement Date
and Termination Date of the Lease in writing, in the event that adjustment is
necessary due to delay in Landlord's delivery of the Premises on or prior to the
Commencement Date, delay in any initial improvements to the Premises, or any
other cause. In such event, Landlord shall deliver written notice of the
adjustments to the Commencement Date and the Termination Date to Tenant, but in
no event shall the Term of the Lease be reduced by reason of any such
adjustment. Tenant shall indicate its agreement to said adjustments by executing
an original of said notice and delivering same back to Landlord within ten days
after receipt by Tenant. In the event that Tenant shall fail to return said
notice to Landlord, it shall be conclusively deemed that Tenant has approved the
adjustments to the Commencement Date and Termination Date. Any such notice shall
be attached to the Lease.
     If Landlord, for any reason whatsoever, cannot deliver possession of the
Premises to Tenant on the Commencement Date, the Lease shall not be void or
voidable, nor shall Landlord be liable to Tenant for any loss or damage
resulting from Landlord's failure to deliver possession, but in said event, and
subject to any provision to the contrary in any agreement with Landlord
concerning initial improvements to the Premises, all rentals due from Tenant
shall be waived for the period between the Commencement Date and the date when
Landlord delivers possession of the Premises to Tenant. No delay in delivery of
possession of the Premises by Landlord to Tenant shall operate to extend the
Term. Notwithstanding anything in the Lease to the contrary, in the event
Landlord is unable to deliver the Premises to Tenant within 90 days after the
execution of the Lease, Tenant shall have the right to terminate the Lease upon
written notice to the Landlord.


                  Acceptance of Premises/Initial Improvements
                  -------------------------------------------

     Tenant warrants and represents that it has made a complete and thorough
inspection of the Premises, and that the Premises is satisfactory for the Use
which Tenant intends.
     If an Exhibit "C" relating to initial improvements to the Premises is
attached to the Lease, then construction of the "Tenant Improvements" (as
defined in Exhibit "C") upon and in the Premises shall be constructed as
described in the plans and specifications referenced in Exhibit "C", and, upon
occupying the Premises, Tenant shall be deemed to have accepted the Premises in
its then-existing condition, subject to completion of any punch-list items
relating to the Tenant Improvements contemplated by Exhibit "C."
     Tenant acknowledges that neither Landlord nor any agent of Landlord has
made any representation as to the condition of the Premises, or the suitability
of the Premises for Tenant's intended Use. TENANT HEREBY WAIVES ANY IMPLIED
WARRANTY BY LANDLORD THAT THE PREMISES IS SUITABLE FOR TENANT'S INTENDED
COMMERCIAL PURPOSE.

                                      -1-
<PAGE>

                        II.  BASE RENT/SECURITY DEPOSIT

                                   Base Rent
                                   ---------

     Tenant shall pay Base Rent to Landlord in advance, without demand,
deduction, or set off, in the amounts and for the periods of time as set forth
in the Basic Lease Information.
     The first monthly installment of Base Rent, plus Tenant's first monthly
installment of "Operating Expenses" (as defined below), shall be due upon the
final execution of the Lease by all parties. Thereafter, monthly installments of
Base Rent and Operating Expenses shall be due on or before the first day of each
calendar month following the Commencement Date. If the Commencement Date occurs
on a day other than the first day of a calendar month, or if the expiration of
the Term occurs on a day other than the last day of a calendar month, the Base
Rent and Operating Expenses shall be prorated.

                             Interest/Late Charge
                             --------------------

     Any amount due from Tenant to Landlord, if not paid when due, shall bear
interest from the date due until paid at the rate of ten percent per annum,
provided that interest shall not be payable on late charges incurred by Tenant
nor on any amounts upon which late charges are paid by Tenant. Payment of
interest by Tenant shall not excuse or cure any "Event of Default" (as defined
below) by Tenant pursuant to the terms of the Lease. All payments received from
Tenant by Landlord shall be applied by Landlord to Tenant's obligations first
accruing.
     Tenant hereby acknowledges that late payment by Tenant to Landlord of Base
Rent, "Operating Expenses," or "Additional Rent" (as said terms are defined
below) will cause Landlord to incur costs not contemplated by the Lease, the
exact amount of which will be extremely difficult to ascertain. Such costs
include, but are not limited to, processing and accounting charges, late fees
which may be imposed upon Landlord, and inconvenience costs. Accordingly, if any
installment of Base Rent, Operating Expenses, or Additional Rent, or any other
sum due from Tenant under the Lease, shall not be received by Landlord within
five days after written notice of such failure is provided by Landlord to
Tenant. Tenant shall pay to Landlord a late charge equal to six percent of such
overdue amount. The parties hereby agree that such late charge represents a fair
and reasonable estimate of the costs Landlord will incur by reason of late
payment by Tenant, and that said charge does not constitute a penalty.
Acceptance of such late charge by Landlord shall in no event constitute a waiver
of Tenant's default with respect to such overdue amount, nor prevent Landlord
from exercising any of the rights and remedies granted to Landlord under the
Lease.

                               Security Deposit
                               ----------------

     Upon Tenant's execution of the Lease, Tenant shall deposit with Landlord
the Security Deposit, which sum shall be held by Landlord to secure Tenant's
obligations under the Lease. Landlord may apply all or any portion of the
Security Deposit to any unpaid Base Rent, "Operating Expenses," or "Additional
Rent" (as said terms are defined below) due from Tenant, or to cure any other
defaults of Tenant. If Landlord uses all or any portion of the Security Deposit,
Tenant shall restore the Security Deposit to its full amount within ten days
after Landlord's written request. Tenant's failure to do so shall be deemed an
"Event of Default" (as defined below) under the Lease. No interest shall be paid
by Landlord to Tenant on the Security Deposit. Landlord shall not be required to
keep the Security Deposit separate from its other accounts, and no trust
relationship is created with respect to the Security Deposit. The Security
Deposit is not a prepayment of Tenant's monthly rent obligations, and may not be
used by Tenant as such; it is expressly understood that the Security Deposit
does not and shall not constitute Tenant's "last month's rent." Upon any
termination of the Lease not resulting from Tenant's default, and after Tenant
has vacated the Premises in the manner required by the Lease and otherwise
timely performed its obligations pursuant to the Lease throughout the Term,
Landlord shall refund the remaining portion of the Security Deposit to Tenant.
     If Landlord assigns its interest in the Lease, the Premises, or the
Building, the Security Deposit shall be deemed to have been assigned to the
assignee. Landlord has no further liability to Tenant for return of the Security
Deposit to Tenant after any such assignment, and Tenant agrees to look solely to
any such assignee for return of the Security Deposit. Tenant may not assign,
encumber, or attempt to assign or encumber the Security Deposit.


                           III.  OPERATING EXPENSES

                                Additional Rent
                                ---------------

     All payments or reimbursements required to be made by Tenant pursuant to
the terms of the Lease, other than Base Rent, shall constitute "Additional
Rent."

                                      -2-
<PAGE>

                                   Net Lease
                                   ---------

     The Lease is a net lease, and Base Rent shall be paid to and received by
Landlord net of all costs and expenses to Landlord, other than taxes upon the
income of Landlord from all sources. Tenant shall pay Tenant's Proportionate
Share of all "Operating Expenses" (as defined below) paid or incurred by
Landlord during the Term.

                              Operating Expenses
                              ------------------

     Tenant shall pay, as Additional Rent, Tenant's Proportionate Share of all
costs incurred by Landlord in owning, operating, and maintaining the Project and
the facilities and services provided for the common use of Tenant and other
tenants of the Project, if any (collectively, "Operating Expenses"). Operating
Expenses shall include, but not be limited to, the following items:

     (1)       "Taxes" (as defined below), and the cost of any tax consultant
               employed to assist Landlord in determining the fair tax valuation
               of the Project or reasonably protesting an assessed valuation,
     (2)       the cost of all utilities used in the Project or upon the real
               property where the Project is located, which utilities costs are
               not billed separately to a tenant of the Project,
     (3)       the premiums for all insurance maintained by Landlord with
               respect to the Project,
     (4)       the costs of repairs, replacements, and general maintenance of
               the Project (other than replacement of the roof, foundation, and
               exterior walls of the Project), including, but not limited to,
               sidewalks, landscaping, service areas, mechanical rooms which
               service the Project and not a specific tenant, non-exclusive
               parking areas, Project exteriors, downspouts, gutters, pipes,
               ducts, conduits, wires, and driveways (excluding such costs paid
               by proceeds of insurance or by other parties, and alterations
               attributable solely to tenants of the Project other than Tenant),
     (5)       wages and salaries (including management fees) of all employees
               engaged in the operation, repair, replacement, and maintenance of
               the Project, including payroll taxes, insurance, and benefits
               relating to said wages and salaries,
     (6)       all supplies and materials used in the operation, maintenance,
               and repair of the Project,
     (7)       the cost of all capital improvements made to the Project which,
               although capital in nature, may reasonably be expected to reduce
               the normal operating costs of the Project, as well as all capital
               improvements made in order to comply with any law, rule, or
               regulation promulgated after the date of the Lease by any
               governmental authority, which cost of capital improvements shall
               be amortized over the useful economic life of such improvements
               as determined by Landlord, in accordance with generally accepted
               accounting principals,
     (8)       all maintenance, repair, and service costs, including the cost of
               service or maintenance contracts with independent contractors for
               the operation, maintenance, or repair of the Project, including,
               but not limited to, alarm service, window cleaning, elevator
               maintenance, and vermin extermination,
     (9)       the costs of dues, assessments, and other charges applicable to
               the Project payable to any property or community owners'
               association under restrictive covenants or deed restrictions to
               which the Project is subject, and
     (10)      all other operating, management, and other expenses incurred by
               Landlord in connection with the operation of the Project.

Operating Expenses shall not include the following:

     (1)       any costs for interest, amortization, or other payments on loans
               by Landlord,
     (2)       expenses incurred in leasing or procuring tenants,
     (3)       legal expenses incurred by Landlord, other than those incurred
               for the general benefit of the Project or the Project's tenants,
     (4)       allowances, concessions, and other costs of renovating or
               otherwise improving space for occupants of the Project or vacant
               space in the Project,
     (5)       federal income taxes imposed on or measured by the income of
               Landlord from the operation of the Project,
     (6)       rents under ground leases,
     (7)       costs incurred in selling, syndicating, financing, mortgaging, or
               hypothecating any of Landlord's interest in the Project,
     (8)       the costs of any capital improvements required by a governmental
               authority with regard to another tenant's use, such costs being
               paid by the applicable tenant, and
     (9)       costs for repairs caused by Landlord's gross negligence or
               willful misconduct.

                                      -3-
<PAGE>

                                     Taxes
                                     -----

     Tenant shall pay, as part of the Project's Operating Expenses, Tenant's
Proportionate Share of all real property taxes, assessments, or governmentally
imposed fees or charges (and any tax or assessment levied wholly or partly in
lieu of same, except for late fees, penalties, and interest) levied, assessed,
confirmed, imposed, or which becomes a lien against the Project (which for the
purposes of defining "Taxes" shall include the land underlying the Project) or
which are payable during the Term (collectively, "Taxes"). In the event that the
Project is not separately assessed for tax purposes, then the Taxes paid by
Tenant shall be Tenant's Proportionate Share of the product obtained by
multiplying the total of the Taxes levied against the tax parcel of which the
Project is a part by a fraction, the numerator of which is the rentable area of
the Project, and the denominator of which is the total rentable area of all
improvements located within the tax parcel of which the Project is a part. If,
during the Term, there is levied, assessed, or imposed upon Landlord a capital
levy or other tax directly on the rent or a franchise tax, assessment, levy, or
charge measured by or based, in whole or in part, upon rent, then all such
taxes, assessments, levies, or charges, or the part of same so measured or
based, shall be included within the term "Taxes."
      Tenant hereby agrees that any and all protests before the applicable
appraisal review board shall be conducted, if at all, solely by Landlord, and
Tenant shall have no rights to any such protest. Tenant hereby waives any rights
and privileges which it may have pursuant to Texas Tax Code (Property Tax Code)
sections 41.413 and 42.015 (as amended from time to time) to conduct any such
protest.

                     Payment of Monthly Operating Expenses
                     -------------------------------------

     On the same day that Base Rent is due, Tenant shall pay at the same time
and in the same manner an amount equal to 1/12 of Landlord's estimate of
Tenant's Proportionate Share of annual Operating Expenses for the then-current
calendar year. Said monthly payments are to be based upon Landlord's estimate of
the Operating Expenses for the year in question, and shall be increased or
decreased annually to reflect the projected annual Operating Expenses for that
applicable year. Within 90 days after the close of each calendar year, or as
soon after such 90-day period as is reasonably practicable, Landlord shall
deliver to Tenant a statement of actual Operating Expenses for said calendar
year. If Tenant's total payments for Operating Expenses for any year are less
than Tenant's actual Proportionate Share of Operating Expenses for that year,
Tenant shall pay the difference to Landlord within 30 days after Landlord's
request for payment of same. If Tenant's total payments for Operating Expenses
for any year are more than Tenant's actual Proportionate Share of Operating
Expenses for that year, Landlord shall either retain such excess and credit it
against Tenant's future Base Rent obligations next accruing, or pay such excess
to Tenant within 30 days after determining Tenant's actual Proportionate Share
of Operating Expenses for that year. The obligations of Landlord and Tenant
under this paragraph with respect to reconciliation between estimated payments
and actual Operating Expenses for the last year of the Term shall survive the
termination of the Lease.
     In the event Tenant reasonably disputes the annual Operating Expenses,
Tenant, at Tenant's sole cost and expense, shall be entitled to examine, review,
and audit, upon reasonable notice and during Landlord's normal business hours,
the books and records relating to such Operating Expenses at the place where
such books and records are normally kept. In the event that any such examination
reveals that Tenant has overpaid by more than five percent, Tenant shall be
entitled to such overpayment, and the costs incurred in connection with such
audit, not to exceed $500.00, shall be borne by Landlord. Any such audit shall
be made within 12 months after Tenant's receipt of Landlord's annual statement
for such Operating Expenses.


                         IV.  PERSONAL PROPERTY TAXES

     Tenant shall 1) before delinquency pay all taxes levied or assessed against
any personal property, fixtures, or alterations placed in the Premises, and 2)
upon the request of Landlord, deliver to Landlord receipts from the applicable
taxing authority or other evidence acceptable to Landlord to verify that such
taxes have been paid. If any such taxes are levied or assessed against Landlord
or Landlord's property and (i) Landlord pays them, or (ii) the assessed value of
Landlord's property is increased as a result and Landlord pays the increased
taxes, then Tenant shall pay to Landlord such taxes within ten days after
Landlord's request for payment.


               V.  LANDLORD'S MAINTENANCE AND REPAIR OBLIGATIONS

     Except as otherwise provided in the Lease, and except for damage caused by
any act or omission of Tenant, its employees, contractors, invitees, or agents,
Landlord shall maintain the foundation, roof, and structural portions of the
exterior walls (collectively, the "Project's Structure") in good order,
condition, and repair; however, Landlord shall neither be responsible nor liable
for 1) any such work until Tenant delivers to Landlord written notice of

                                      -4-
<PAGE>

the need for such work, or 2) alterations to the Project's Structure required by
law because of Tenant's use of the Premises (which alterations shall be
performed by Tenant). The Project's Structure does not include skylights,
windows, glass, plate glass, doors, special storefronts, office entries, or the
interior surfaces of walls within the Premises, all of which shall be maintained
by Tenant. All requests for repairs or maintenance that are the responsibility
of Landlord must be made in writing to Landlord, and Landlord shall have a
reasonable time within which to perform such repairs or maintenance. Landlord
shall not be liable to Tenant for any damages or inconvenience, and Tenant shall
not be entitled to any damages, nor to any abatement or reduction of rent, by
reason of any repairs, alterations, or additions made by Landlord under the
Lease. Landlord's liability for any defects, repairs, replacement, or
maintenance for which Landlord is responsible under the Lease shall be limited
to the cost of performing such work. Nothing in this provision shall entitle
Tenant to make any repairs, alterations, or additions to the Premises at
Landlord's expense, or to terminate the Lease based on the physical condition of
the Premises. Tenant hereby expressly waives the benefits of any statute now or
hereafter in effect which would otherwise afford Tenant the right to make
repairs at Landlord's expense, or to terminate the Lease because of Landlord's
failure to keep the Premises or the Project in good order, condition, and
repair.


               VI.  TENANT'S MAINTENANCE AND REPAIR OBLIGATIONS

     Tenant shall keep and maintain the Premises in a good and clean condition
at its sole cost and expense, and Tenant shall perform all maintenance and
perform all repairs on the Premises, and shall replace such portions of the
Premises as may be necessary to maintain the Premises and all parts of the
Premises in good condition, order, and repair. Janitorial services to the
Premises shall be obtained by Tenant, at Tenant's sole expense.
     Tenant shall, at Tenant's sole expense, maintain all hot water, heating,
and air conditioning systems for the Premises; provided, however, that if
Landlord deems that Tenant is not adequately maintaining such systems, Landlord
may require Tenant to enter into a regularly-scheduled preventive
maintenance/service contract with a maintenance contractor for servicing all hot
water, heating, and air conditioning systems within the Premises. Any such
maintenance contractor and the contract must be approved by Landlord. Any such
service contract must include all services suggested by the applicable equipment
manufacturer within the operation/maintenance manual, and must become effective
(and a photocopy of said contract delivered to Landlord) within 30 days of the
date Tenant takes possession of the Premises. Tenant expressly covenants and
warrants to keep that portion of the Premises not required to be maintained by
Landlord in good order, condition, and repair, promptly making all necessary
repairs and replacements, including, but not limited to, windows, glass, plate
glass, doors, any special office entry, interior walls and finish work, floors
and floor covering, heating and air conditioning systems, dock boards, truck
doors, dock bumpers, paving, plumbing work and fixtures, pest extermination. In
addition, Tenant shall, at Tenant's sole expense, repair any damage to the
Project caused by the acts or omissions of Tenant, its employees, contractors,
agents, or invitees. It is the intention of Landlord and Tenant that, at all
times during the Term, Tenant shall maintain the area in front of and in the
rear of the Premises in an attractive, well-maintained, and fully operative
condition.
     Tenant shall maintain, at Tenant's sole cost and expense, any existing fire
sprinkler system within the Premises in accordance with all applicable federal,
state, county, or city regulations. In addition, Tenant shall, within 90 days
following the Commencement Date, and at Tenant's sole cost and expense, install
and maintain such additional fire sprinkler equipment in the Premises as may be
required for Tenant's Use by applicable state or local building regulation,
municipal ordinance, or regulation of the local fire marshall having
jurisdiction over the Premises.
     In the event Tenant fails to maintain the Premises in accordance with the
Lease, Landlord shall have the right, but not the obligation, to enter upon the
Premises and perform needed maintenance and repairs, and, in such event, Tenant
shall promptly reimburse Landlord for the cost of such entry, repairs, and
maintenance, which reimbursement shall be collectible as Additional Rent. Any
such Additional Rent shall be payable to Landlord within 30 days after receipt
by Tenant of written invoice and notice from Landlord.


                  VII.  ALTERATIONS, ADDITIONS, IMPROVEMENTS

     Tenant shall not make any alterations, additions, or improvements to the
Premises without the prior written consent of Landlord, which shall not
unreasonably be withheld. Landlord shall not be required to notify Tenant as to
whether it consents to any proposed alteration, addition, or improvement until
Landlord has 1) received completed plans and specifications for the proposed
alteration, addition, or improvement, which plans are sufficiently detailed to
allow construction of the work depicted to be performed in a good and
workmanlike manner, 2) received completed cost estimates for the proposed
alteration, addition, or improvement, and 3) had a reasonable opportunity (not
to exceed 30 days) to review said plans and specifications and cost estimates.
If the proposed alteration, addition, or improvement will affect the Project's
Structure, HVAC system, or mechanical, electrical, or plumbing systems, then the
plans and specifications must be prepared by a licensed engineer

                                      -5-
<PAGE>

reasonably acceptable to Landlord. Landlord's approval of any plans and
specifications shall not be a representation that the plans or the work depicted
will comply with law or be adequate for any purpose, but shall merely be
Landlord's consent to performance of the work. Upon completion of any
alteration, addition, or improvement, Tenant shall deliver to Landlord accurate,
reproducible, "as built" plans for same.
     Tenant may without Landlord's consent erect shelves, bins, machinery, and
trade fixtures provided that such items 1) do not alter the basic character of
the Premises or the Project, 2) do not overload or damage the Project's
Structure, and 3) may be removed without damage to the Premises.
     Unless Landlord specifies in writing otherwise, all physically attached
alterations, additions, and improvements shall be Landlord's property when
installed in the Premises. All work performed by Tenant in the Premises
(including that relating to the installation, repair, replacement, or removal of
any item) shall be performed in accordance with applicable law and with
Landlord's specifications and requirements, in a good and workmanlike manner,
and so as not to damage or alter the Project's Structure or the Premises. Tenant
shall pay all costs incurred or arising out of all alterations, additions, or
improvements in or to the Premises (unless the parties have agreed to the
contrary in an Exhibit "C" to the Lease), and Tenant shall not permit a
mechanics' or materialmen's lien to be asserted against the Premises. Upon
request by Landlord, Tenant shall deliver to Landlord proof of payment
reasonably satisfactory to Landlord of all costs incurred or arising out of any
alterations, additions, or improvements. In connection with any such
alterations, additions, or improvements, Tenant shall pay to Landlord an
administration fee of five percent of all costs incurred for such work.


                                 VIII.  SIGNS

     Tenant shall not place, install, or attach any signage, decorations,
advertising media, blinds, draperies, window treatments, bars, or security
installations to the Premises or the Project without Landlord's prior written
approval. Tenant shall repair, paint, and/or replace any portion of the Premises
or the Project damaged or altered as a result of Tenant's signage when same is
removed (including, without limitation, any discoloration of the Project).
Tenant shall not (a) make any changes to the exterior of the Premises or the
Project, (b) install any exterior lights, decorations, balloons, flags,
pennants, banners, or paintings, or (c) erect or install any signs, window or
door lettering, decals, window or storefront stickers, placards, decorations, or
advertising media of any type visible from the exterior of the Premises without
Landlord's prior written consent. Landlord shall be required to notify Tenant as
to whether it consents to any sign within 30 days after it has received
detailed, to-scale drawings of the proposed sign specifying design, material
composition, color scheme, and method of installation. Notwithstanding anything
to the contrary within this paragraph, Tenant's signage must comply with the
Project's sign criteria as established by Landlord from time-to-time.


                                IX.  UTILITIES

     Tenant shall obtain and pay for all water, gas, electricity, heat,
telephone, sewer, sprinkler, and other utilities and services used at the
Premises, together with any deposits, taxes, penalties, surcharges, maintenance
charges, and the like pertaining to Tenant's use of utilities in the Premises.
All utilities shall be obtained by Tenant, separately metered, and opened in
Tenant's name and for Tenant's account with the applicable utility companies.
Landlord shall not be liable for any interruption or failure of utility service
to the Premises. Tenant shall be solely responsible for providing janitorial
services to the Premises at Tenant's sole cost and expense.


                                 X.  INSURANCE

                  Worker's Compensation/Employer's Liability/
                  -------------------------------------------
                               Tenant's Property
                               -----------------

     Tenant shall procure and maintain throughout the Term, for the protection
of Tenant and Landlord as their interests may appear, policies of insurance
which afford the following coverages:

     1.   worker's compensation - statutory limits;
     2.   employer's liability, in amounts not less than $250,000.00 each
          accident, bodily injury by accident; $250,000.00 policy limit each
          employee, bodily injury by disease; and
     3.   property insurance insuring Tenant's business personal property and
          tenant improvements against direct risk of loss, broad form coverage,
          and insuring Tenant's business income, with 100 percent current
          replacement cost valuation for business personal property, and one
          year's total anticipated net earnings for business income.

                                      -6-
<PAGE>

                         Commercial General Liability
                         ----------------------------

     Tenant shall procure and maintain throughout the Term a policy or policies
of commercial general liability insurance, at Tenant's sole cost and expense, in
amounts of not less than $2,000,000.00 each occurrence limit, $2,000,000.00
general aggregate limit, $2,000,000.00 products/completed operations aggregate
limit, and $2,000,000.00 personal injury and advertising injury limit, or such
other amounts as Landlord may from time to time reasonably require, covering
bodily injury and property damage liability, and including contractual liability
coverage, written by insurance companies rated "A" or better, with a financial
rating of not less than Class "X" by A.M. Best Company Inc., and otherwise
acceptable to Landlord, insuring Tenant, and Landlord as an additional insured,
against any and all liability to the extent obtainable for injury to or death of
a person or persons or damage to property occasioned by or arising out of or in
connection with the use, operation, and occupancy of the Premises, during the
policy period, regardless of when the claim is made. All coverage shall be
primary to Landlord's insurance. Landlord's insurance shall be noncontributory
with and in excess to such insurance. Tenant shall furnish to Landlord,
concurrent with execution of the Lease, certificates of insurance and such other
evidence satisfactory to Landlord of the maintenance of all insurance coverage
required under this article, including a photocopy of the Additional Insured-
Managers or Lessors of Premises Endorsement, and Tenant shall obtain and deliver
to Landlord a written obligation on the part of each insurance company to notify
Landlord at least 30 days prior to cancellation or material change of any such
insurance. Tenant shall deliver renewal certificates at least 30 days prior to
the expiration of each policy. Landlord makes no representation that the limits
of liability specified by the Lease to be carried by Tenant are adequate to
protect Tenant. Tenant shall provide any such additional coverage as Tenant
deems adequate.

                          Tenant's Failure To Acquire
                          ---------------------------

     If Tenant shall fail to acquire the insurance required pursuant to this
article, or fail to pay the premiums for said insurance, or fail to deliver the
required certificates or policies to Landlord within ten days after written
notice from Landlord that it has not received such certificates or policies,
Landlord may, but is not obligated to, in addition to any other rights or
remedies available to Landlord under the Lease, without the necessity of any
notice to Tenant or time to cure, each of which are expressly waived, acquire
such insurance and pay the requisite premiums for said insurance, which premiums
shall be payable as Additional Rent by Tenant to Landlord upon demand, together
with accrued interest as provided in the Lease.


                             XI.  CASUALTY DAMAGE

     Tenant shall give immediate written notice to Landlord of any damage caused
to or suffered by the Premises or the Project. Tenant shall be responsible for
any subsequent waste which may occur to the Premises or the Project in the event
Tenant fails to timely notify Landlord of any damage to the Premises or the
Project.
     If the Premises or the Project are totally destroyed, or so partially
damaged such that Tenant's use of the Premises is materially interfered with,
from a risk which is wholly covered by insurance proceeds made available to
Landlord for such purpose, Landlord shall proceed with reasonable diligence to
repair the damage or destruction, and the Lease shall not terminate; provided,
however, that if in the opinion of Landlord's architect the Project or repairs
cannot reasonably be completed within 180 days after the date of Landlord's
actual knowledge of such damage, either party may at its election terminate the
Lease by delivering written notice of said election to the other party, in which
event the rent payable for any unexpired portion of the Lease shall be abated,
effective upon the date such damage occurred.
     If the Premises or the Project are substantially damaged, in such a way
that Tenant's use of the Premises is materially interfered with, from a risk not
wholly covered by insurance made available to Landlord for repair or
reconstruction, Landlord may terminate the Lease by delivering written notice of
said termination to Tenant, in which event all rights and obligations under the
Lease shall cease and terminate, effective upon the date such damage occurred,
except any liability of Tenant accruing prior to the Lease being terminated.
     If the Premises or the Project are substantially damaged during the final
24 months of the Term or any renewal Term, Landlord shall not be required to
rebuild or repair the damage to the Project or the Premises unless Tenant
exercises a renewal option, if any, within 15 days after the date of receipt by
Landlord of Tenant's notification of the occurrence of the damage. If Tenant
does not elect to exercise its renewal option, or if there is no previously
unexercised renewal option contained within the Lease, Landlord shall have the
option to terminate the Lease, and rent shall be abated for the unexpired
portion of the Term, effective upon the date such damage occurred.
     If the Lease is not terminated pursuant to the preceding paragraphs, then
Landlord shall proceed immediately and shall use reasonable diligence to rebuild
or repair the Project and the Premises to substantially the condition in which
they existed prior to the damage; provided, however, that Landlord shall not be
required to rebuild, repair, or replace any part of the partitions, fixtures,
additions, or other improvements or personal property required to be covered by
Tenant's insurance described in article XI above.  If the Premises is untenable,
in

                                      -7-
<PAGE>

whole or in part, during the period beginning on the date such damage occurred,
and ending on the date of substantial completion of Landlord's repair or
restoration work, then, under such circumstances, the rent for such period shall
be reduced to such extent as may be fair and reasonable under the circumstances,
as determined by that portion of the Premises which may reasonably be utilized
by Tenant. Except for abatement of rent, Tenant shall have no claim against
Landlord for any loss suffered by Tenant due to damage or destruction of the
Project or the Premises, or for any work or repair undertaken by Landlord as the
result of any such damage or destruction.

             XII.  LIABILITY/INDEMNIFICATION/WAIVER OF SUBROGATION

                             Landlord's Liability
                             --------------------

     Landlord shall not be liable to Tenant, or those claiming by, through, or
under Tenant, including, but not limited to, Tenant's agents, officers,
directors, employees, or invitees, for any injury to, or death of, any person or
persons, or the damage, theft, destruction, loss, or loss of use of any property
or inconvenience (a "Loss") caused by casualty, theft, fire, third parties, or
any other matter, specifically including, but not limited to, injury or damage
from fire, steam, electricity, gas, water, rain, snow, ice, or hail which may
leak or flow from or into any part of the Premises, the breakage, leakage,
destruction, or other defects of pipes, sprinklers, wires, appliances, plumbing,
air conditioning, or lighting fixtures of the Premises or the Project, and
including losses arising through repair or alteration of any part of the
Premises or the Project, or failure to make repairs, or from any other cause,
unless such Loss is caused by Landlord's gross negligence or willful misconduct.
This exculpation of Landlord shall specifically include any damage arising from
any act or neglect of any other tenant of the Project.

                           Indemnification by Tenant
                           -------------------------

     Tenant shall indemnify, defend, and hold harmless Landlord, its successors,
assigns, agents, employees, contractors, partners, directors, officers, and
affiliates (collectively, the "Indemnified Parties") from and against all fines,
suits, losses, costs, liabilities, claims, demands, actions, and judgments of
every kind or character 1) arising from Tenant's failure to perform its
covenants under the Lease, 2) recovered from or asserted against any of the
Indemnified Parties on account of any Loss to the extent that any such Loss may
be incident to, arise out of, or be caused, either proximately or remotely,
wholly or in part, by Tenant or any other person entering upon the Premises
under or with Tenant's express or implied invitation or permission, 3) arising
from or out of the occupancy or use by Tenant, or arising from or out of any
occurrence in the Premises, however caused, or 4) suffered by, recovered from,
or asserted against any of the Indemnified Parties by the employees, agents,
contractors, or invitees of Tenant or its subtenants or assignees, regardless of
whether Landlord's negligence caused such loss or damage. However, such
indemnification of the Indemnified Parties by Tenant shall not be applicable if
such loss, damage, or injury is wholly caused by the gross negligence or willful
misconduct of Landlord or any of its duly authorized agents or employees.

                             Waiver of Subrogation
                             ---------------------

     The parties desire to avoid liability to each other's insurance companies.
Accordingly, Landlord and Tenant, each for itself and for any person or entity
claiming through it (including any insurance company claiming by way of
subrogation), hereby waive any and every claim which arises or may arise in its
favor against the other party to the Lease, and the other party's officers,
directors, and employees, for any and all loss or damage to property, to the
extent (but only to the extent) that the waiving party who suffers such loss or
damage is actually compensated by insurance, or would be compensated by the
insurance policies contemplated in article XI above, if such policies were
maintained as required by the Lease. Each party agrees to have such insurance
policies properly endorsed so as to make them valid notwithstanding this waiver,
if such endorsement is required to prevent a loss of insurance.


                                  XIII.  USE

                                   Premises
                                   --------

     The Premises shall be used only for the permitted Use as stated in the
Basic Lease Information. No other use of the Premises may be made without
Landlord's prior written approval, which shall be granted or withheld at
Landlord's sole discretion. Without Landlord's prior written approval, which
shall be granted or withheld at Landlord's sole discretion, Tenant shall not use
the Premises to receive, store, or handle any product, material, or merchandise
that is explosive, highly flammable, or hazardous. Outside storage is
prohibited. Tenant shall be solely responsible for complying with all laws
applicable to the Use, occupancy, and condition of the Premises. Tenant shall
not permit any objectionable or unpleasant odors, smoke, dust, gas, light,
noise, or vibrations to emanate from the Premises; nor take any other

                                      -8-
<PAGE>

action that would constitute a nuisance or would disturb, unreasonably interfere
with, or endanger Landlord or any other person; nor permit the Premises to be
used for any purpose or in any manner that would 1) void any insurance on the
Premises or the Project, 2) increase the insurance risk, or 3) cause the
disallowance of any sprinkler credits. Tenant shall pay to Landlord on demand
any increase in the cost of any insurance on the Premises or the Project
incurred by Landlord that is caused by Tenant's use of the Premises or because
Tenant vacates the Premises.
     Tenant represents and warrants to Landlord that Tenant's intended Use of
the Premises is solely for business or commercial purposes, and not for
personal, family, or household purposes.

                                 Parking Areas
                                 -------------

     Tenant and its employees and invitees shall have the non-exclusive right to
use, in common with others, any parking areas associated with the Premises which
Landlord may from time-to-time designate for such use, at an allocation of no
less than one parking spaces per 1500 square feet of the Premises, subject to 1)
such reasonable rules and regulations as Landlord may promulgate from time to
time, and 2) rights of ingress and egress of other tenants and their employees,
agents, and invitees. Landlord shall not be responsible for enforcing Tenant's
parking rights against third parties.


                    XIV.  VACATION/RESTORATION/HOLDING OVER

                                  Inspection
                                  ----------

     Landlord and Landlord's agents and representatives may enter the Premises
during business hours to inspect the Premises; to make such repairs as may be
required or permitted under the Lease; to perform any unperformed obligations of
Tenant under the terms of the Lease; and to show the Premises to prospective
purchasers, mortgagees, ground lessors, and (during the last nine months of the
Term) prospective tenants, provided that such activities shall not unreasonably
interfere with Tenant's occupancy or Use. During the last 12 months of the Term,
Landlord may erect a sign on the Premises indicating that the Premises is
available for lease.

                                    Vacation
                                    --------

     Tenant shall notify Landlord in writing of its intention to vacate the
Premises at least 60 days before Tenant will vacate the Premises, unless such
vacation will occur upon expiration of the Term or any extended term of the
Lease. Such notice shall specify the date on which Tenant intends to vacate the
Premises (the "Vacation Date"). At least 30 days before the Vacation Date,
Tenant shall arrange to meet with Landlord for a joint inspection of the
Premises. After such inspection, Landlord shall prepare a list of items that
Tenant must perform before the Vacation Date. If Tenant fails to arrange for
such inspection, then Landlord may conduct such inspection. If Tenant fails to
perform such work before the Vacation Date, then Landlord may perform such work
at Tenant's cost. Tenant shall pay as Additional Rent all costs incurred by
Landlord in performing such work, less the Security Deposit, within 30 days
after Landlord's request for payment.
     Notwithstanding anything in this paragraph to the contrary, Tenant shall
not be responsible for any items or costs which are Landlord's obligations
pursuant to the Lease.

                            Restoration of Premises
                            -----------------------

     Upon the Termination Date, or the earlier termination of the Lease, Tenant
shall 1) deliver the Premises to Landlord with all improvements located upon the
Premises in good repair and condition, reasonable wear and tear excepted
(subject to Tenant's maintenance obligations), and with the HVAC system and hot
water equipment, light and light fixtures (including ballasts), and overhead
doors and related equipment in good working order, 2) deliver to Landlord all
keys to the Premises, and 3) remove all signage placed by or at Tenant's request
upon the Premises, the Project, or the land upon which the Project is located.
All fixtures, alterations, additions, and improvements (whether temporary or
permanent) shall be Landlord's property and shall remain on the Premises, except
as provided in the next two sentences. Provided that Tenant has performed all of
its obligations pursuant to the Lease, Tenant may remove all unattached trade
fixtures, furniture, and personal property placed on the Premises by Tenant (but
Tenant shall not remove any such item which was paid for, in whole or in part,
by Landlord). Additionally, Tenant shall remove all alterations, additions,
improvements, fixtures, equipment, wiring, furniture, and other property as
Landlord may instruct Tenant in writing at least 90 days prior to the
Termination Date (or the termination date under any applicable option to extend
Term), or within 30 days after the earlier termination of the Lease, and, in
such event, restore the Premises to the condition as received by Tenant prior to
the Commencement Date. All items not so removed shall, at the option of
Landlord, be deemed abandoned by Tenant and may be appropriated, sold, stored,
destroyed, or otherwise disposed of by Landlord without notice to Tenant, and
without any obligation to

                                      -9-
<PAGE>

account for such items, and Tenant shall pay as Additional Rent the costs
incurred by Landlord in connection with such disposition. All work required of
Tenant under this paragraph shall be coordinated with Landlord, and shall be
performed in a good and workmanlike manner in accordance with all laws, and so
as not to damage the Premises or the Project, or unreasonably interfere with
other tenants' use of their premises. Tenant shall, at its sole expense, repair
all damage to the Premises or the Project caused by any work performed by Tenant
pursuant to this paragraph. Tenant's obligation to perform under this covenant
shall survive the expiration or earlier termination of the Lease.

                                 Holding Over
                                 ------------

     If Tenant fails to vacate the Premises at the end of the Term, or upon the
earlier termination of the Lease, then Tenant shall be a tenant at will, and
Tenant shall pay, in addition to all applicable Additional Rent due under the
Lease, a daily Base Rent equal to 150 percent of the daily Base Rent payable
during the last month of the Term. Additionally, Tenant shall reimburse Landlord
for, and defend, indemnify, and hold harmless Landlord from, any damage,
liability, and expense (including attorneys' fees and expenses) incurred because
of such holding over. No payments of money by Tenant to Landlord after the
expiration of the Term or the earlier termination of the Lease shall reinstate,
continue, or extend the Term, and no extension of the Term shall be valid unless
it is in writing and signed by Landlord and Tenant.

                         XV.  ASSIGNMENT AND SUBLETTING

                                    Transfer
                                    --------

     Tenant shall not, without the prior written consent of Landlord, which
consent shall not be unreasonably withheld or delayed, 1) advertise that any
portion of the Premises is available for lease, or cause or allow any such
advertisement, 2) assign, transfer, or encumber the Lease or any estate or
interest in the Lease, whether directly or by operation of law, 3) permit any
other entity to become Tenant under the Lease by merger, consolidation, or other
reorganization, 4) if Tenant is an entity other than a corporation whose stock
is publicly traded, permit the transfer of an ownership interest in Tenant so as
to result in a change in the current control of Tenant, 5) sublet any portion of
the Premises, 6) grant any license, concession, or other right of occupancy of
any portion of the Premises, or 7) permit the use of the Premises by any parties
other than Tenant (any of the events listed above being a "Transfer").

                              Landlord's Consent
                              ------------------

     If Tenant requests Landlord's consent to a Transfer, then Tenant shall
provide Landlord with a written description of all terms and conditions of the
proposed Transfer, photocopies of the proposed documentation, and the following
information about the proposed transferee: name and address; reasonably
satisfactory information about its business and business history; its proposed
use of the Premises; banking, financial, and other credit information; and
general references sufficient to enable Landlord to determine the proposed
transferee's creditworthiness and character. Tenant shall reimburse Landlord for
its reasonable attorneys' fees and other expenses incurred in connection with
considering any request for its consent to a Transfer. Landlord's consent to any
Transfer shall not be unreasonably withheld. If Landlord consents to a proposed
Transfer, then the proposed transferee shall deliver to Landlord a written
agreement whereby it expressly assumes Tenant's obligations under the Lease
(provided, however, that any transferee of less than all of the space in the
Premises shall be liable only for obligations under the Lease that are properly
allocable to the space subject to the Transfer, and only to the extent of the
rent it has agreed to pay Tenant for said space). Landlord's consent to a
Transfer shall not release Tenant from performing its obligations under the
Lease, but rather Tenant and its transferee shall be jointly and severally
liable for performance of the Lease. Landlord's consent to any Transfer shall
not waive Landlord's discretion or rights as to any subsequent Transfer. If an
"Event of Default" (as defined below) occurs while the Premises or any part of
the Premises is subject to a Transfer, then Landlord, in addition to its other
remedies, may collect directly from such transferee all rents becoming due to
Tenant and apply such rents against Tenant's rent obligations. Tenant authorizes
its transferees to make payments of rent directly to Landlord upon receipt of
written notice from Landlord to do so.

                        Landlord's Option to Terminate
                        ------------------------------

     Landlord may, within 30 days after submission of Tenant's written request
for Landlord's consent to a Transfer, terminate the Lease as of the date the
proposed Transfer was to be effective. If Landlord exercises this option to
terminate, Tenant may, within ten days of receipt of Landlord's election to
terminate, rescind its request for Landlord's consent to a Transfer, in which
event the Lease shall be reinstated. If the Lease is terminated, Landlord may
thereafter lease the Premises to the prospective transferee (or to any other
person or entity) without liability to Tenant.

                                      -10-
<PAGE>

                                 Excess Rental
                                 -------------

     Tenant hereby assigns, transfers, and conveys all consideration received by
Tenant under any Transfer, which is in excess of the rents payable by Tenant
under the Lease, and Tenant shall hold such amounts in trust for Landlord and
pay them to Landlord within ten days after receipt by Tenant. The determination
of such excess rental shall exclude all direct, reasonable, and documented
buildout costs, legal fees, and brokerage expenses incurred by Tenant in
connection with the Transfer, said costs to be amortized on a straight line
basis over the entire term of the Transfer. Any "free rent" to the transferee
shall expressly not, however, be excluded in the determination of excess rental.


                              XVI.  CONDEMNATION

     If more than 50 percent of the Premises is taken for any public or quasi-
public use by right of eminent domain or private purchase in lieu of eminent
domain (a "Taking"), and the Taking prevents or materially interferes with the
use of the remainder of the Premises for the purpose for which it was leased to
Tenant, either party may terminate the Lease by delivering to the other written
notice of such termination within 30 days after the Taking, in which case rent
shall be abated during the unexpired portion of the Term, effective on the date
of such Taking. If (a) less than 50 percent of the Premises is subject to a
Taking, or (b) more than 50 percent of the Premises is subject to a Taking, but
the Taking does not prevent or materially interfere with the use of the
remainder of the Premises for the purpose for which it was leased to Tenant,
then neither party may terminate the Lease, but the rent payable during the
unexpired portion of the Term shall be reduced to such extent as may be fair and
reasonable under the circumstances. All compensation awarded for any Taking
shall be the property of Landlord, and Tenant assigns any interest it may have
in any such award to Landlord; provided, however, that Landlord shall have no
interest in any award made to Tenant for loss of business, goodwill, or for the
taking of Tenant's trade fixtures, if a separate award for such items is made to
Tenant. Landlord shall have complete procedural control over eminent domain
proceedings affecting the Premises, and shall have complete control over
decisions regarding the acceptance or rejection of any offer made in eminent
domain, other than a separate award made to Tenant. The terms of this paragraph
shall also be applicable in the event Landlord conveys in lieu of condemnation.


                            XVII.  QUIET ENJOYMENT

     Provided Tenant pays all Base Rent, Operating Expenses, and Additional
Rent, and no "Event of Default" (as defined below) exists, Tenant may peaceably
and quietly enjoy the Premises during the Term, without disturbance or hindrance
from Landlord or any party claiming by, through, or under Landlord, but not
otherwise, subject to the terms of the Lease and any deed of trust, mortgage,
ground lease, ordinance, lease, utility easement, and/or other agreements to
which the Lease is subordinate.

                           XVIII.  EVENTS OF DEFAULT

     Tenant shall be in default under the Lease upon the occurrence of any of
the following events (an "Event of Default"):
     (a)  Tenant fails to pay any portion of any Base Rent, Operating Expenses,
Additional Rent, or any other payment or reimbursement required under the Lease,
when due, and said failure continues for a period of five days from the date
such payment was due; or
     (b)  Tenant fails to perform or comply with or violates any term,
provision, or covenant of the Lease, and such failure of performance,
noncompliance, or violation continues for ten days after notice of same by
Landlord to Tenant; or
     (c)  Tenant makes a transfer of the bulk of its assets or a transfer in
fraud of creditors, or makes an assignment for the benefit of creditors; or
     (d)  Tenant files or consents or acquiesces to the filing of a petition in
bankruptcy, or a petition seeking postponement or relief of indebtedness under
the federal bankruptcy laws, or under the laws of the United States or of any
state; or
     (e)  Tenant files or consents or acquiesces to the filing of a request for
the appointment of a trustee or receiver for all or any portion of Tenant's
property; or
     (f)  a petition or request for relief is filed against Tenant in any court
of the United States or in any state seeking relief in any bankruptcy,
reorganization, composition,  extension,  arrangement, or insolvency proceeding,
or under any plan for the cancellation, postponement, or adjustment of
indebtedness, which petition or request for relief was not consented or
acquiesced to by Tenant, as the case may be, and subsequently said petition or
request is approved or granted or Tenant  shall  be  adjudicated  bankrupt  or
such  proceedings  are  not dismissed or vacated within 30 days after filing; or
     (g)  Tenant (i) fails to take possession of the Premises within 30 days
after the Commencement Date, unless such failure is not caused by Tenant, or
(ii) abandons or vacates

                                      -11-
<PAGE>

all or a substantial portion of the Premises, or (iii) fails to continuously
operate its business at the Premises for the permitted use as set forth above;
or
     (h)  Tenant makes a Transfer of the Premises without the consent of
Landlord; or
     (i)  Tenant or its agents or employees are convicted of a criminal
violation of law for conduct allegedly occurring on or related to the Premises;
or
     (j)  Tenant fails to discharge any lien placed upon the Premises within 20
days after any such lien or encumbrance is filed against the Premises.


                                XIX.  REMEDIES

                        Termination of Lease/Possession
                        -------------------------------

     Upon any Event of Default, Landlord may, in addition to all other rights
and remedies afforded Landlord under the Lease or by law, take any of the
following actions:
     (1)  terminate the Lease by giving Tenant written notice of said
termination, in which event Tenant shall pay to Landlord the sum of all rent
accrued under the Lease through the date of termination, plus all "Default
Costs" (as defined below), plus an amount equal to (a) the total rent that
Tenant would have been required to pay for the remainder of the Term, discounted
to present value at a per annum rate equal to the "prime rate" as published on
the date the Lease is terminated by the Wall Street Journal, Southwest Edition,
in its listing of "money rates," minus (b) the then-present fair rental value of
the Premises for such period, similarly discounted; or
     (2)  terminate Tenant's right to possess the Premises without terminating
the Lease by giving Tenant written notice of said termination, in which event
Tenant shall pay to Landlord all rent and other amounts accrued under the Lease
to the date of termination of possession, plus all "Default Costs" (as defined
below) due from time to time, plus all rent and other sums required under the
Lease to be paid by Tenant during the remainder of the Term, diminished by any
net sums thereafter received by Landlord through reletting the Premises during
such period. Landlord shall utilize commercially reasonable efforts to mitigate
damages when Tenant has breached the Lease and abandoned the Premises. Without
limiting the generality of the preceding sentence, the parties expressly agree
that Landlord (i) may lease other comparable available premises in the Project
without being first obligated to re-let the Premises, (ii) will not be required
to incur out-of-pocket expenses to clean and/or refurbish the Premises, other
than customary commissions and legal fees, (iii) will not be obligated to re-let
the Premises at rental rates below then-prevailing market rental rates, (iv) may
elect to assign or sublet the Premises to an existing tenant of the Building
prior to reletting the Premises to a third party, (v) may decline to re-let the
Premises to a prospective tenant not consistent with the existing tenant mix of
the Building, and (vi) may require any prospective tenant to demonstrate
financial capacity commensurate with other tenants of the Building. Tenant shall
not be entitled to the excess of any consideration obtained by reletting over
the rent due under the Lease. Reentry by Landlord in the Premises shall not
affect Tenant's obligations under the Lease for the unexpired Term; rather,
Landlord may, from time to time, bring action against Tenant to collect amounts
due by Tenant, without the necessity of Landlord waiting until the expiration of
the Term. Unless Landlord delivers written notice to Tenant expressly stating
that it has elected to terminate the Lease, all actions taken by Landlord to
exclude or dispossess Tenant of the Premises shall be deemed to be taken under
this paragraph. If Landlord elects to proceed under this paragraph, it may, at
any time thereafter, elect to terminate the Lease under the preceding paragraph.
      Additionally, without notice, Landlord may alter locks or other security
devices at the Premises to deprive Tenant of access to the Premises.

                                 Default Costs
                                 -------------

     Tenant shall pay to Landlord all costs ("Default Costs") incurred by
Landlord (including court costs and reasonable attorneys' fees and expenses) in
1) obtaining possession of the Premises, 2) removing and storing Tenant's or any
other occupant's property, 3) repairing, restoring, altering, remodeling, or
otherwise putting the Premises into condition acceptable to a new tenant, 4) if
Tenant is dispossessed of the Premises and the Lease is not terminated,
reletting all or any part of the Premises (including brokerage commissions, cost
of tenant finish work, and other costs incidental to such reletting), 5)
performing Tenant's obligations which Tenant failed to perform, and 6)
enforcing, or in advising Landlord of, its rights, remedies, and recourses due
to Tenant's default.

                          Tenant's Personal Property
                          --------------------------

     If Landlord repossesses the Premises pursuant to the authority granted by
the Lease, then Landlord shall have the right to 1) keep in place and use, or 2)
remove and store, at Tenant's reasonable expense, all of the furniture,
fixtures, equipment, and other property in the Premises, including that which is
owned by or leased to Tenant. Landlord may relinquish possession of all or any
portion of such furniture, fixtures, equipment, and other property to any person
(a "Claimant") who presents to Landlord a photocopy of any instrument
represented by Claimant to have been executed by Tenant (or any predecessor of
Tenant)

                                      -12-
<PAGE>

granting Claimant the right, under various circumstances, to take possession of
such furniture, fixtures, equipment, or other property, without the necessity on
the part of Landlord to inquire into the authenticity or legality of the
instrument. Landlord may, at its option and without prejudice to or waiver of
any rights it may have, 1) escort Tenant to the Premises to retrieve any
personal belongings of Tenant and/or its employees not covered by Landlord's
statutory lien or the security interest described below, or 2) obtain a list
from Tenant of the personal property of Tenant and/or its employees that is not
covered by Landlord's statutory lien or the security interest described below,
and make such property available to Tenant and/or Tenant's employees; however,
Tenant first shall pay in cash all costs and estimated expenses to be incurred
by Landlord in connection with the removal of such property.

                            Non-Waiver by Landlord
                            ----------------------

     Landlord's acceptance of rent following an Event of Default shall not waive
Landlord's rights regarding such Event of Default. Landlord's receipt of rent
with knowledge of any Event of Default by Tenant under the Lease shall not be a
waiver of such Event of Default, and no waiver by Landlord of any provision of
the Lease shall be deemed to have been made unless set forth in writing and
signed by Landlord. The failure of Landlord to insist at any time upon strict
performance of any of the terms of the Lease, or to exercise any option, right,
power, or remedy contained in the Lease is not a waiver of said right or remedy
in the future.

                               Rights Cumulative
                               -----------------

     The rights of Landlord stated above are in addition to any and all other
rights that Landlord has or may have either at law or in equity, and Tenant
agrees that the rights granted by the Lease to Landlord are commercially
reasonable.


                 XX.  LANDLORD DEFAULT/LIMITATION OF LIABILITY

     As used in the Lease, the term "Landlord" shall mean only the current owner
or owners of the fee title to the Premises, or the leasehold estate under a
ground lease to the Premises, at the applicable time. Each Landlord shall be
obligated to perform the obligations of Landlord under the Lease only during the
time that the particular Landlord holds or owns such interest or title. Any
Landlord who transfers his, her, or its title or interest shall be relieved of
all liability with respect to the obligations of Landlord under the Lease
performable on or after the date of transfer. However, each Landlord shall
deliver to its transferee all funds previously paid by Tenant, if the funds have
not yet otherwise been applied or earned under the terms of the Lease.
     Tenant shall give written notice to Landlord of any failure by Landlord to
perform any of its obligations under the Lease, and to any ground lessor,
mortgagee, or beneficiary under any deed of trust encumbering the Premises whose
name and address shall have been previously furnished by Landlord to Tenant in
writing.  Landlord shall not be considered in default under the terms of the
Lease unless Landlord fails to cure within 30 days after receipt of Tenant's
notice.  However, if the failure requires more than 30 days to cure, Landlord
shall not be in default if such cure is commenced within the 30-day period, and
if Landlord further diligently pursues said cure to completion.
     Neither Landlord nor Tenant shall not be required to perform any obligation
under the terms of the Lease or be liable or responsible for any loss or damage
resulting from its failure to perform so long as performance is delayed or
prevented by force majeure, acts of God, strikes, lockouts, material or labor
shortages, embargo, civil riot, war, revolution, rebellion, civil war,
insurrection, flood, natural disaster, and any other cause not reasonably within
the control of the respective party.
     Notwithstanding anything to the contrary set forth in the Lease, it is
specifically understood and agreed by Tenant that there shall be absolutely no
personal liability on the part of Landlord with respect to any of the terms,
covenants, or conditions of the Lease, and Tenant shall look solely to the
equity, if any, of Landlord in the Premises for the satisfaction of each and
every remedy of Tenant, in the event of any breach by Landlord of any of the
terms, covenants, or conditions of the Lease to be performed by Landlord; such
exculpation of personal liability to be absolute and without any exception
whatsoever, and no other property or assets of Landlord shall be subject to
levy, execution, or other enforceable procedure for the satisfaction of Tenant's
remedies. Notwithstanding anything to the contrary as set forth in the Lease, it
is specifically understood and agreed that any liability which may arise as a
consequence of the execution of the Lease by or on behalf of the Trustees under
the Will and of the Estate of James Campbell, Deceased, shall be a liability of
the Estate of James Campbell and not the personal liability of any trustee,
corporate officer of a trustee, employee, or beneficiary of the Estate of James
Campbell.

                                XXI.  MORTGAGES

     The Lease shall be subordinate to any deed of trust, mortgage, or other
security instrument (a "Mortgage"), and any ground lease, master lease, or
primary lease (a "Primary

                                      -13-
<PAGE>

 Lease") that now or hereafter covers any portion of the Premises and Project
(the mortgagee under any Mortgage or the lessor under any Primary Lease is
referred to as "Landlord's Mortgagee"), and to increases, renewals,
modifications, consolidations, replacements, and extensions of same. However,
any Landlord's Mortgagee may elect to subordinate its Mortgage or Primary Lease
(as the case may be) to the Lease by delivering written notice of such
subordination to Tenant. The provisions of this paragraph shall be self-
operative, and no further instrument shall be required to effect such
subordination; however, Tenant shall, from time to time, within ten days after
written request to do so by Landlord, execute any instruments that may be
required by any Landlord's Mortgagee to evidence the subordination of the Lease
to any such Mortgage or Primary Lease. If Tenant fails to execute the same
within such ten-day period, Landlord may execute the same as attorney-in-fact
for Tenant.
     Tenant shall attorn to any party succeeding to Landlord's interest in the
Premises, whether by purchase, foreclosure, deed in lieu of foreclosure, power
of sale, termination of lease, or otherwise, provided that the successor agrees
to assume the obligations and liabilities of Landlord, and upon such party's
request, Tenant shall execute such agreements confirming such attornment as such
party may reasonably request. Tenant shall not seek to enforce any remedy it may
have for any default on the part of Landlord without first giving written notice
by certified mail, return receipt requested, specifying the default in
reasonable detail to any Landlord's Mortgagee whose address has been previously
given to Tenant, and affording such Landlord's Mortgagee a reasonable
opportunity to perform Landlord's obligations under the Lease.
     Notwithstanding any such attornment or subordination of a Mortgage or
Primary Lease to the Lease, Landlord's Mortgagee shall not be liable for any
acts of any previous landlord, shall not be obligated to install any Tenant
improvements, and shall not be bound by any amendment to which it did not
consent in writing, nor to any payment of rent made more than one month in
advance.

                          XXII.  TENANT ENCUMBRANCES

     Tenant has no authority, express or implied, to create or place any lien or
encumbrance of any kind or nature whatsoever upon, or in any manner to bind,
Landlord's property, the interest of Landlord or Tenant in the Premises, or the
rent due under this Lease in favor of any person dealing with Tenant, including
those who may furnish materials or perform labor for any construction or
repairs. Tenant shall pay or cause to be paid all sums due for any labor
performed or materials furnished in connection with any work performed on the
Premises by or at the request of Tenant. Tenant shall give Landlord immediate
written notice upon Tenant learning of the placement of any lien or encumbrance
against the Premises.

                           XXIII.  LANDLORD'S LIEN

     In addition to the statutory landlord's lien, Tenant grants to Landlord, to
secure performance of Tenant's obligations under the Lease, a security interest
in all goods, inventory, equipment, fixtures, furniture, improvements, chattel
paper, accounts, general intangibles, and other personal property of Tenant now
or hereafter situated on or relating to Tenant's use of the Premises, and all
proceeds of same (the "Collateral"), and the Collateral shall not be removed
from the Premises without the consent of Landlord until all obligations of
Tenant under the Lease have been fully performed. Upon the occurrence of an
Event of Default, Landlord may, in addition to all other remedies provided by
law or under the Lease, without notice or demand except as provided below,
exercise the rights afforded a secured party under the Uniform Commercial Code
as adopted by the State of Texas. In connection with any public or private sale,
Landlord shall give Tenant ten days' prior written notice of the time and place
of any public sale of the Collateral, or of the time after which any private
sale or other intended disposition of the Collateral is to be made, which is
agreed by Tenant to be a reasonable notice of such sale or other disposition.
Landlord may also file a photocopy of the Lease or this provision as a financing
statement to perfect its security interest in the Collateral. Landlord agrees to
subordinate its landlord's lien to that of a bona-fide third party commercial
lender.


                                 XXIV.  NOTICES

      Each provision of the Lease or of any applicable laws and other
requirements with reference to the sending, mailing, or delivering of notice or
the making of any payment under the Lease shall be deemed to be complied with
when and if the following steps are taken:
      (a)  all Base Rent, Operating Expenses, and Additional Rent shall be
payable to Landlord at Landlord's Address for Notice, or at such other address
as Landlord may specify from time to time by written notice delivered in
accordance with this article.  Tenant's obligation to pay rent shall not be
deemed satisfied until such rent has been actually received by Landlord;
      (b)  all payments required to be made by Landlord to Tenant under the
Lease shall be payable to Tenant at Tenant's Address for Notice, or at such
other address as Tenant may specify from time to time by written notice
delivered in accordance with this article; and

                                      -14-
<PAGE>

     (c) any written notice or document required or permitted to be delivered
shall be deemed to be delivered upon the earlier to occur of 1) tender of
delivery (in the case of a hand-delivered notice), 2) deposit in the United
States mail, postage prepaid, certified mail, return receipt requested, or 3)
receipt by facsimile transmission with a confirmation notice by United States
first-class mail, in each case addressed to the parties at the respective
Address for Notice, or at such other address as they have previously specified
by written notice delivered in accordance with this article. If Landlord has
attempted to deliver notice to Tenant at Tenant's Address for Notice, or at such
other address as Tenant may have previously specified by written notice
delivered in accordance with this article, but such notice was returned or
acceptance of same was refused, then Landlord may post such notice in or on the
Premises, which notice shall be deemed delivered to Tenant upon the posting of
said notice.

                           XXV.  HAZARDOUS MATERIALS

     The term "Hazardous Substances," as used in the Lease, shall mean
pollutants, contaminants, toxic or hazardous wastes, or any other substances,
the removal of which is required or the use of which is restricted, prohibited,
or penalized by any "Environmental Law," which term shall mean any law relating
to health, pollution, or protection of the environment. Tenant hereby agrees
that 1) no activity will be conducted on the Premises that will produce any
Hazardous Substances, except for such activities that are part of the ordinary
course of Tenant's business activities (the "Permitted Conditions"), provided
such Permitted Conditions are conducted in accordance with all Environmental
Laws and have been approved in advance in writing by Landlord; 2) the Premises
will not be used in any manner for the storage of any Hazardous Substances
except for any temporary storage of such materials that are used in the ordinary
course of Tenant's business (the "Permitted Substances"), provided such
Permitted Substances are properly stored in a manner and location satisfying all
Environmental Laws and approved in advance in writing by Landlord; 3) no portion
of the Premises will be used as a landfill or a dump; 4) Tenant will not install
any underground tanks of any type; 5) Tenant will not allow any surface or
subsurface conditions to exist or come into existence that constitute, or with
the passage of time may constitute, a public or private nuisance; and 6) Tenant
will not permit any Hazardous Substances to be brought onto the Premises, except
for the Permitted Substances. If at any time during or after the Term, the
Premises is found to be contaminated with Hazardous Substances, Tenant shall
defend, indemnify, and hold Landlord harmless from all claims, demands, actions,
liabilities, costs, expenses, damages, and obligations of any nature arising
from or as a result of the use of the Premises by Tenant. Unless expressly
identified on an addendum to this Lease, as of the date of the Lease there are
no Permitted Conditions or Permitted Substances for purposes of the foregoing
provision, and none shall exist unless and until approved in advance and in
writing by Landlord. Landlord may enter the Premises and conduct environmental
inspections and tests as it may require from time to time, provided that
Landlord shall use reasonable efforts to notify Tenant 24 hours in advance and
minimize any interference with Tenant's business. Such inspections and tests
shall be conducted at Landlord's expense, unless they reveal the presence of
Hazardous Substances (other than any Permitted Substances), or that Tenant has
not complied with the requirements set forth in this article, in which case
Tenant shall reimburse Landlord for the cost of such inspections and tests
within ten days after Landlord's request for payment of same.

     See, Exhibit "E" for additional terms and conditions of the Lease relating
to environmental matters.

                            XXVI.  EMERGENCY POWER

     Auxiliary HVAC/Diesel Generator/Fuel Storage Tank Outside of Premises
     ---------------------------------------------------------------------

     Tenant shall have the right, subject to 1) all regulations of applicable
jurisdictional authorities, 2) the terms of exhibit "E" of the Lease, and 3)
Landlord's prior written approval as to location, size, and capacity to install
a) auxiliary HVAC to the Premises, b) one diesel generator, and c) a maximum 500
gallon fuel storage tank for emergency back-up power. To the extent that the
placement of the auxiliary HVAC, diesel generator, or fuel storage tank may
displace parking spaces, such displaced parking spaces shall be subtracted from
Tenant's allotment of parking spaces described above. Tenant shall have the
right to test the generator one time per week at a time mutually-agreed upon in
writing between Landlord and Tenant.

                             Revocation of Approval
                             ----------------------

     The parties expressly agree that any right granted by the preceding
paragraph to utilize auxiliary HVAC, a diesel generator, or a fuel storage tank
outside of the Premises may be unilaterally and immediately rescinded by
Landlord 1) in the event of written notification from any governmental authority
that such usage of auxiliary HVAC or the diesel generator, or use of the fuel
storage tank outside of the Premises is unlawful or constitutes a public or
private nuisance, if said condition is not corrected within ten days after said
notice, or 2) in the event of the issuance of any criminal or civil citation by
any governmental authority with regard to

                                      -15-
<PAGE>

Tenant's usage of the auxiliary HVAC, diesel generator, or the fuel storage tank
outside of the Premises. In any of the above events, Landlord may, without
further notice to Tenant, rescind any prior authorization for auxiliary HVAC, a
diesel generator, or a fuel storage tank outside of the Premises, and, upon said
rescission, Tenant shall immediately cease usage of and remove the auxiliary
HVAC, or the diesel generator, or the fuel storage tank from the outside of the
Premises.


                              XXVII.  COLLOCATION

                                  Collocation
                                  -----------

     Tenant shall have the right to collocate certain customer equipment in the
Premises, for the purpose of connecting such customer equipment to Tenant's
facilities related to the provision of Tenant's telecommunications services to
Tenant's customers.  Tenant shall defend, indemnify, and hold Landlord harmless
from and against, any and all claims of and from such customers relating to such
collocation.  So long as such collocation does not over-burden the Premises or
the building of which the Premises is a part, Tenant shall not be required to
pay to, or share with Landlord, any profits, collocation fees, or charges
received by Tenant from the customers whose equipment is collocated.  No tenancy
or subtenancy shall be created by collocation of equipment allowed pursuant to
this paragraph.

                         Right to Serve Other Tenants
                         ----------------------------

     Tenant shall have the right to provide telecommunications services to
other tenants of the Project.  Tenant shall be permitted reasonable access to
the Project for the purposes of installing, operating, repairing, and
maintaining the fiber optic cable, facilities, and equipment (collectively, the
"System") connecting Tenant's network to interested tenants of the Project.
Tenant may offer its services through its fiber optic network to other tenants
in the Project in the same manner as any third-party vendor.  Prior to any
installation of the System, Tenant shall consult with Landlord to determine an
appropriate entrance plan, and Tenant shall not proceed with installation of the
System until Landlord's written approval has been obtained.  Tenant will perform
any installation in such a manner so as not to interrupt operations at the
Project.  Tenant will restore the Project to its original condition and bear all
costs for rearrangement or restoration, as necessary.


                            XXVIII.  MISCELLANEOUS

                               Context/Captions
                               ----------------

     Words of any gender used in the Lease shall include any other gender, and
words in the singular shall include the plural, unless the context otherwise
requires.  The captions inserted in the Lease are for convenience only and in no
way affect the interpretation of the Lease.

                            Transfer/Authorization
                            ----------------------

     Landlord may transfer and assign, in whole or in part, its rights and
obligations in the Premises, the Project, and the real property that are the
subject to the Lease, in which case Landlord shall have no further liability
under the Lease, other than obligations accruing prior to such transfer.  Each
party shall furnish to the other, promptly upon demand, a corporate resolution,
proof of due authorization by partners, or other appropriate documentation
evidencing the due authorization of such party to enter into the Lease.

                              Time of the Essence
                              -------------------

     Time is of the essence in the performance of all of Landlord's and Tenant's
duties and obligations pursuant to the Lease.

                              Tenant Documentation
                              --------------------

     Tenant shall, from time to time, within ten days after written request by
Landlord, deliver to Landlord, or Landlord's designee, 1) a certificate of
occupancy for the Premises, 2) audited financial statements for Tenant and any
guarantor of Tenant's obligations under the Lease, 3) evidence reasonably
satisfactory to Landlord that Tenant has performed its obligations under the
Lease (including evidence of payment of the Security Deposit), and 4) an
estoppel certificate stating that the Lease is in full effect, the date to which
rent has been paid, the unexpired Term, the status of any alleged Landlord
defaults, and such other factual matters pertaining to the Lease as may be
requested by Landlord.  Tenant's obligation to furnish the above-described items
in a timely fashion is a material inducement for Landlord's

                                      -16-
<PAGE>

execution of the Lease, and Tenant's failure to timely deliver any such items
within ten days after written notice shall constitute an Event of Default under
the Lease. If Tenant fails to execute any such estoppel certificate within such
ten-day period, Landlord may do so as attorney-in-fact for Tenant.

                               Entire Agreement
                               ----------------

     The Lease constitutes the entire agreement between Landlord and Tenant with
respect to the subject matter of the Lease, and contains all of the covenants
and agreements of Landlord and Tenant with respect to the Lease.  Landlord and
Tenant each acknowledge that no representations, inducements, promises, or
agreements, whether oral or written, have been made by Landlord or Tenant, or
anyone acting on behalf of Landlord or Tenant, which are not contained within
the Lease, and any prior agreements, promises, negotiations, or representations
not expressly set forth in the Lease are of no effect.  The Lease may not be
altered, changed, or amended except by an instrument in writing signed by both
parties.

                     Survival of Obligations upon Vacating
                     -------------------------------------

     All obligations of Tenant not fully performed by the end of the Term shall
survive, including, without limitation, all payment obligations concerning the
condition and repair of the Premises.  Upon the expiration of the Term, and
within ten days after Tenant vacates the Premises, Tenant shall pay to Landlord
any amount reasonably estimated by Landlord as necessary to put the Premises in
good condition and repair, reasonable wear and tear excluded.  Tenant shall
also, prior to vacating the Premises, pay to Landlord the amount, as estimated
by Landlord, of Tenant's obligation for Operating Expenses for the year in which
the Term ends, less any credits due Tenant.  All such amounts shall be used and
held by Landlord for payment of such obligations of Tenant, with Tenant being
liable for any additional costs for such items upon demand by Landlord, with any
excess to be returned to Tenant after all such obligations have been determined
and satisfied, as the case may be.  Any Security Deposit held by Landlord may be
credited against the amount due by Tenant under this paragraph.

                                  No Surrender
                                  ------------

     No act by Landlord shall be an acceptance of a surrender of the Premises,
and no agreement to accept a surrender of the Premises shall be valid unless it
is in writing and signed by Landlord.

                    Illegality/Invalidity/Unenforceability
                    --------------------------------------

     If any provision of the Lease is illegal, invalid, or unenforceable, then
the remainder of the Lease shall not be affected, and in lieu of each such
provision, there shall be added, as a part of the Lease, a provision as similar
in terms to such illegal, invalid, or unenforceable clause or provision as may
be possible and be legal, valid, and enforceable.

                             Broker Indemnification
                             ----------------------

     Landlord and Tenant each warrant to the other that it has not dealt with
any broker or agent in connection with the Lease, except as identified in the
Basic Lease Information.  Tenant and Landlord shall each indemnify the other
against all costs, attorneys' fees, and other liabilities for commissions or
other compensation claimed by any broker or agent claiming the same by, through,
or under the indemnifying party.

                                Confidentiality
                                ---------------

     The terms and conditions of the Lease are confidential, and neither
Landlord nor Tenant shall disclose the terms of the Lease to any third party
except as may be 1) required by law or regulatory agency, 2) mutually agreed to,
or 3) required to enforce the parties' rights under the Lease.

                       Governing Law/Place of Performance
                       ----------------------------------

     The Lease shall be governed by and construed in accordance with the laws of
the State of Texas, and all obligations of the parties under the Lease are
performable in Harris County, Texas.

                          Representation of Authority
                          ---------------------------

     If Tenant is a corporation, each individual executing the Lease on behalf
of Tenant represents and warrants to Landlord that he or she is duly authorized
to execute and deliver the Lease on behalf of the corporation, in accordance
with a duly adopted resolution of the board of directors of said corporation,
and that the Lease is binding upon said corporation.

                                      -17-
<PAGE>

                                   Exhibits
                                   --------

     The exhibits specified in the Basic Lease Information are attached to the
Lease and are hereby incorporated into the Lease for all intents and purposes as
if fully set forth at length verbatim.

                   Facsimile Execution/Counterpart Execution
                   -----------------------------------------

     The parties agree that execution of the Lease by either party may be done
by facsimile execution, which shall be binding for all intents and purposes.
Further, the Lease may be executed in one or more signature page counterparts,
each of which when combined with the remainder of the Lease shall constitute one
and the same document.

                              No Security Services
                              --------------------

     Tenant acknowledges and represents to Landlord that Tenant recognizes that
Landlord is not obligated to and will not provide any security services for the
Premises or the Project.


     TENANT ACKNOWLEDGES THAT 1) IT HAS INSPECTED AND ACCEPTS THE PREMISES IN AN
"AS IS, WHERE IS" CONDITION, 2) THE PROJECT AND IMPROVEMENTS COMPRISING THE SAME
ARE SUITABLE FOR THE PURPOSE FOR WHICH THE PREMISES IS LEASED, AND FOR TENANT'S
INTENDED COMMERCIAL PURPOSE, AND LANDLORD HAS MADE NO WARRANTY, REPRESENTATION,
COVENANT, OR AGREEMENT WITH RESPECT TO THE MERCHANTABILITY OR FITNESS FOR ANY
PARTICULAR PURPOSE OF THE PREMISES, 3) THE PREMISES IS IN GOOD AND SATISFACTORY
CONDITION, 4) NO REPRESENTATIONS AS TO REPAIR OF THE PREMISES, NOR PROMISES TO
ALTER, REMODEL, OR IMPROVE THE PREMISES HAVE BEEN MADE BY LANDLORD (UNLESS AND
EXCEPT AS MAY BE SET FORTH IN EXHIBIT "C" ATTACHED TO THE LEASE, IF ONE SHALL BE
ATTACHED, OR AS MAY BE OTHERWISE EXPRESSLY SET FORTH IN THE LEASE), AND 5) THERE
ARE NO REPRESENTATIONS OR WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, THAT
EXTEND BEYOND THE DESCRIPTION OF THE PREMISES.


     Executed by Tenant on this 21/st/ day of December, 1999.

TENANT:
------
EBASEONE CORPORATION


                                             APPROVED AS TO FORM:
                                             -------------------
by: /s/ Scott Feuless
    --------------------------------

name: Scott Feuless
      ------------------------------
                                             /s/ Margaret C. Fitzgerald
                                             --------------------------
title: Chief Technology Officer              counsel for Tenant
       -----------------------------

     Executed by Landlord on this 22/st/ day of December, 1999.

LANDLORD:
--------

THE TRUSTEES UNDER THE WILL
AND OF THE ESTATE OF JAMES
CAMPBELL, DECEASED, ACTING IN
THEIR FIDUCIARY AND NOT IN
THEIR INDIVIDUAL CAPACITIES
                                             APPROVED AS TO FORM:
                                             -------------------


by: /s/ Dorine Holsey Streeter
    --------------------------------
                                             [ILLEBIBLE]
                                             --------------------------
its:  Director Mainland Properties           JONES & CANNON,
     -------------------------------
                                             a professional corporation
by: /s/ Sydni L. Roberson, CPM, CCIM         440 North Center
    --------------------------------         Arlington, Texas 76011

its: Senior Asset Manager
     -------------------------------

                                      -18-
<PAGE>

                                  EXHIBIT "A"

Exhibit "A" is a graphic depiction of the floor plan of the building in which
the premises leased by the company are shaded. The depiction shows the area
around the leased facility and the buildings surrounding the leased facility.
The bottom of the depiction states "BELTWAY 8 FEEDER ROAD." The right side of
the depiction states "I-45 FEEDER ROAD." The bottom left of the depiction shows
the adjacent buildings to the leased facility. The buildings identified in the
depiction beginning from the bottom left of the depiction and moving in a
clockwise manner are: LEVEL 3 COMMUNICATIONS, LLC, VACANT, CAPROCK, OFFICE
DEPOT, CONVERGYS, VACANT, PAGE NET, VACANT, VACANT, ITC, (shaded area showing
our leased facility, MARCO'S, PANDEM STAFFING, VACANT, VACANT, VACANT, VACANT,
VACANT, VACANT, VACANT, TSC DENTAL, SPLIT ROCK. The upper right of the depiction
is a legend for the map, stating "Greenspoint Technology Center, SITE PLAN."

<PAGE>

                                  EXHIBIT "B"


                                   EXHIBIT A
                                   ---------

                                   THE LAND
                                   --------

     That certain parcel or parcels of land consisting of approximately twenty-
one and four hundred ninety-eight thousandths (21.498) acres, located in the
County of Harris, State of Texas, legally described as follows:

     All of that certain 21.498 acres of land comprised of 21.454 acres being
all of the Restricted Reserve "A", Commons at Greenspoint, according to the plat
thereof filed at Volume 342, Page 126 Harris County Map Records and 1,921 square
feet being out of the Pierce Sullivan Survey, A-749, Harris County, Texas and
being a portion of that certain 2,014 square foot tract as described in a deed
dated May 12, 1989 from AT&T Communications of the Southwest, Inc. to The
Commons at Greenspoint Joint Venture filed in the Official Public Records of
Real Property of Harris County, Texas at Clerk File No. M-173117, Film Code No.
###-##-####.
<PAGE>

                                  EXHIBIT "C"

                      INITIAL IMPROVEMENTS OF THE PREMISES
                        (TENANT IMPROVEMENTS BY TENANT)
                        -------------------------------

     Improvements at Tenant's Expense
     --------------------------------

     (a)  Alterations at Tenant's Expense

     Tenant accepts the Premises in its present condition, "AS IS", without
calling upon Landlord to make any expenditures or to perform any work whatsoever
for the preparation of the Premises for Tenant's use. Tenant shall, at its sole
expense, make the necessary improvements, alterations, and installations (the
"Tenant Improvements") in the Premises required for its business, using a
contractor or contractors who have been approved in writing by Landlord, such
approval not to be unreasonably withheld. Tenant shall comply at its sole
expense with all present and future governmental requirements arising out of, in
connection with, or necessitated by such Tenant Improvements.

     (b)  Approval of Plans

     All Tenant Improvements shall be completed pursuant to working plans and
specifications prepared by a duly registered architect employed by Tenant, at
Tenant's sole expense. Any deficiency in design or construction shall be
Tenant's sole responsibility, regardless of whether such plans and
specifications were previously approved by Landlord. Approval by Landlord of any
of Tenant's drawings, plans, and specifications prepared in connection with any
Tenant Improvements within the Premises shall not constitute a representation or
warranty by Landlord as to the adequacy or sufficiency of such drawings, plans,
and specifications, or the improvements to which they relate, for any use,
purpose, or condition. Any such approval by Landlord shall merely be the consent
of Landlord as required pursuant to this subparagraph. Landlord has made no
representations as to the condition of the Premises, or the Building, or the
need for Tenant to remodel, repair, or decorate.

     Prior to commencing the Tenant Improvements, Tenant shall submit plans and
specifications for such Tenant Improvements to Landlord or its agent, for
Landlord's written approval, which approval shall not unreasonably be withheld,
and for which Landlord shall approve or disapprove within ten days of submission
of said documents by Tenant to Landlord. Landlord's approval of said plans and
specifications may be contingent upon the removal of any or all of the Tenant
Improvements from the Premises, and restoration of the Premises to the condition
existing prior to completion of the Tenant Improvements upon the expiration or
earlier termination of the Lease. All Tenant Improvements to be performed and
completed by Tenant shall be performed in strict accordance with the approved
plans and specifications. Without Landlord's prior written consent, no Tenant
Improvements shall be constructed, nor shall there be any deviation from the
approved plans and specifications, for such Tenant Improvements.

     Unless designated to be removed as discussed in the Lease, and excluding
Tenant's trade fixtures, all Tenant Improvements (whether temporary or permanent
in character, and including, but not limited to, all HVAC equipment and all
other equipment that is in any manner connected to the Building's plumbing
system) made in or upon the Premises, either by Landlord or Tenant, shall become
Landlord's property at the end of the Lease, and shall remain on the Premises,
without compensation to Tenant.

                                      C-1
<PAGE>

     (c)  Permits

     Tenant, at its sole cost and expense, shall file all drawings, plans, and
specifications, pay all fees, and obtain all permits and applications from the
local building department, the department of labor, and other competent
governmental authorities, and shall also obtain a certificate of occupancy (or
equivalent) and such other approvals as may be required to enable Tenant to
lawfully operate within the Premises. Tenant shall promptly furnish to Landlord
true and correct photocopies of all certificates and approvals required by the
applicable governmental authorities. Landlord shall sign all applications
requiring the owner's signature. No work shall be started, or equipment
installed, until all such necessary consents, authorizations, and licenses shall
have first been duly obtained by the Tenant, its contractor, or other persons
performing Tenant Improvements or installing equipment in the Premises on
Tenant's behalf.

     (d)  Performance of Work

     On or before the Commencement Date, Tenant shall, at its sole cost and
expense, substantially complete all work required of it pursuant to the
Landlord-approved plans and specifications. Tenant will be permitted to
enter thePremises for the purpose of performing its obligations to build the
Tenant Improvements, and for the purpose of installing its fixtures and other
equipment, provided (a) Tenant shall have obtained Landlord's written approval
of the plans and specifications for said Tenant Improvements, and (b) Tenant
shall have deposited with Landlord the policies or certificates of insurance
required below. Tenant's activities shall be conducted so as not to unreasonably
interfere with Landlord's activities. Tenant shall, at its sole expense,
promptly remove from the Premises and from the Building all trash which may
accumulate during Tenant's construction of the Tenant Improvements. During such
construction, Tenant shall perform all duties and obligations imposed by this
Lease, including, but not limited to, those provisions relating to insurance and
indemnification, saving and excepting only the obligation to pay rent, which
obligation shall commence on the Commencement Date. All work described in this
paragraph shall be performed only by contractors and subcontractors approved in
writing by Landlord. All such work shall be performed in accordance with all
legal requirements, and in a good and workmanlike manner, so as not to damage
the Premises, the primary structure or structural qualities of the Building, or
plumbing, electrical lines, or other utility transmission facility. All such
work which may affect the HVAC, electrical system, or plumbing must be performed
by workers duly licensed and skilled in their profession and trades. All
materials shall be new, and both workmanship and materials shall be of first-
class quality.

     (e)  Mechanics' Liens

     Tenant shall not permit any mechanics' or materialmen's liens to be filed
against the Premises or the Building for any work performed, materials
furnished, or obligation incurred by or at the request of Tenant. If such a lien
is filed, Tenant shall, within ten days after Tenant has knowledge of such
filing, or within ten days after Landlord has delivered notice of the filing to
Tenant, whichever comes first, either pay the amount of the claim or diligently
contest such lien and deliver to Landlord a bond or other security reasonably
satisfactory to Landlord. If Tenant fails to timely take either such action,
then Landlord may pay the lien claim without inquiry as to the validity of said
claim, and any amount so paid, including expenses and interest, shall be paid to
Landlord within ten days after Landlord has delivered to Tenant an invoice for
such amount.

                                      C-2
<PAGE>

     (f)  Insurance

     Tenant shall require any contractor and subcontractor who is to perform
Tenant Improvements on the Premises to procure and keep in force at said
contractor's expense during such time as work is being performed on the
Premises: comprehensive general liability insurance, including contractor's
liability coverage, contractual liability coverage, completed operations
coverage, broad form property damage endorsement, and contractor's protective
liability coverage to afford protection to the limit, per occurrence, of not
less than the combined single limit of $2,000,000.00 with respect to death,
personal injury, and property damage. All insurance required by the terms of
this Lease shall be maintained with an insurance company authorized to do
business in Texas, and which is reasonably satisfactory to Landlord. Tenant will
cause Tenant's contractors to deposit the policy or policies of such insurance
or certificates of insurance with Landlord prior to commencing any such work,
which policies shall name Landlord or its designee as an additional named
insured, and shall also contain a provision stating that such policy or policies
shall not be cancelled except after 30 days' written notice to Landlord. Such
policy or policies shall include a waiver of subrogation in favor of Landlord.

     (g)  Indemnification

     All work with regard to the Tenant Improvements, including work done at the
Premises or at the Building, shall be at the sole risk of Tenant, and Tenant
shall indemnify and hold Landlord, its trustees, agents, beneficiaries, and
employees, harmless from and against all liability, claims, judgments, or
demands, including attorneys' fees (collectively, the "Liability") arising
directly or indirectly from the obligations undertaken by Tenant with regard to
the Tenant Improvements, excepting only as may be caused by Landlord's gross
negligence or willful misconduct. This indemnity shall include, but not be
limited to, any and all Liability attributable to any bodily injury, sickness,
disease, or death of any person, including Tenant or any contractors, employees,
agents, subcontractors, or independent contractors, or to any injury, damage, or
destruction of or to any tangible property, including the loss of use resulting
from such injury, damage, or destruction; excepting, however, any Liability to
any person or property occasioned or resulting solely from the willful injury of
such person or property by Landlord. The parties hereby expressly agree to this
allocation of risk, and represent that this allocation of risk is a material
inducement for Landlord to enter this Lease. Tenant shall, upon demand by
Landlord, defend any actions or proceedings brought against Landlord with
respect to the matters and items indemnified against in this paragraph, through
counsel fully satisfactory to Landlord provided, however, that Landlord shall
have the right to conduct any such defenses at Tenant's sole cost and expense,
if Landlord chooses to so do.

     (h)  Records

     Tenant shall keep, maintain, and operate full, true, and accurate books of
account and full, true, and complete records with respect to the Tenant
Improvements. Landlord and its representatives shall have full access to such
books and records at all times during regular business hours, and may examine
and audit them. Tenant shall furnish Landlord all statements, information,
vouchers, invoices, and supporting data it reasonably requires with respect to
the Tenant Improvements.

     (i)  Inspections

     Landlord may place its supervisory personnel and representatives on the job
during the course of construction, at Landlord's expense, for the purpose of
making inspections and ensuring that Tenant and Tenant's

                                      C-3
<PAGE>

contractors, suppliers, and materialmen comply with these requirements.
Notwithstanding the foregoing enumeration of restrictions and conditions,
Landlord may at any time during the course of the work on the Tenant
Improvements impose such other restrictions, rules, and conditions as may be
reasonably necessary to ensure the proper completion of the work.

     (j)  Consent

     Nothing contained within this paragraph shall imply any consent or
agreement by the Landlord to subject Landlord's ownership estate to liability
under any mechanics', materialmen's, or other lien law.

     (k)  Americans with Disabilities Act

     Tenant shall be responsible for all costs and expense necessary to ensure
compliance with the Americans with Disabilities Act of 1990.



APPROVED AS TO FORM:                INITIALED:
-------------------                 ---------

/s/ [ILLEGIBLE]                     /s/ [ILLEGIBLE]
---------------------------         ----------------------
JONES & CANNON,                     LANDLORD
 a professional corporation         /s/ [ILLEGIBLE]
440 North Center                    ----------------------
Arlington, Texas 76011              TENANT

                                      C-4
<PAGE>

                                  EXHIBIT "D"

                             RULES AND REGULATIONS
                             ---------------------

1.   All deliveries shall be made to designated service or receiving areas and
     Tenant shall request delivery trucks to approach their service or receiving
     areas by designated service routes and drives. All delivered goods shall be
     moved into Tenant's Premises within a reasonable period of time, and shall
     not be left in parking or receiving areas beyond a reasonable period of
     time. Tenant shall not store equipment or pallets outside the Premises.

2.   Tractor trailers which are unhooked or parked such that the dolly wheels
     are beyond the concrete loading apron shall use steel plates under dolly
     wheels to prevent damage to the asphalt paving surface. In addition, wheel
     blocking shall be available for use. Tractor trailers are to be parked only
     at loading docks during loading or unloading. No parking or storing of such
     trailers shall be permitted on streets adjacent to the Premises.

3.   Forklifts which operate on asphalt paving areas shall not have solid rubber
     tires, but rather shall have tires which will not damage the asphalt.

4.   Tenant is responsible for storage and removal of all Tenant's trash,
     refuse, and garbage. All trash shall be contained in suitable receptacles
     stored behind a screened enclosure at locations approved by Landlord.

5.   Tenant shall not dispose of the following items in sinks or commodes:
     plastic products (plastic bags, straws, boxes); sanitary napkins, tea bags;
     cooking fats, cooking oils; any meat scraps or cutting residue; petroleum
     products (gasoline, naptha, kerosene, lubricating oils); paint products
     (thinner, brushes); or any other items which the same are not designed to
     receive. All areas of the Premises, including vestibules, entrances, doors,
     fixtures, windows and plate glass shall be maintained in a safe, neat, and
     clean condition.

6.   Walls, floors, and ceilings shall not be defaced in any way and no one
     shall be permitted to mark, nail, screw, or drill into, paint or in any way
     mar any Building surface, except that pictures, certificates, licenses, and
     similar items normally used in Tenant's business may be carefully attached
     to the walls by Tenant in a manner to be prescribed by Landlord. Upon
     removal of such items by Tenant any damage to the walls or other surface,
     except minor nail holes, shall be repaired by Tenant.

7.   Tenant shall not permit or suffer the use of any advertising medium which
     extends outside of the Premises, including, without limiting the generality
     of the foregoing, flashing lights, searchlights, loudspeakers, phonographs,
     radios, or television. No radio, television, or other communication antenna
     equipment or device is to be mounted, attached, or secured to any part of
     the roof, exterior surface, or anywhere outside the Premises, without the
     prior written consent of Landlord, which consent shall not be unreasonably
     withheld, conditioned, or delayed.

8.   Tenant shall not permit or suffer merchandise of any kind at any time to be
     placed, exhibited, or displayed outside its Premises, nor shall Tenant use
     the exterior sidewalks or exterior walkways of the Premises to display,
     store, or place any merchandise or goods. No sale of merchandise by tenant
     sale, truckload sale, or the like shall be permitted within the Premises.

9.   Tenant shall not permit or suffer any portion of the Premises to be used
     for lodging purposes.

10.  Tenant will install monitored electronic door locking mechanisms for
     entryways; provided however, Landlord shall be provided access to the
     Premises by Tenant providing keys or passcodes to the Premises.

11.  No windows, doors, or other light or air sources that reflect or admit
     light or air into the office areas shall be covered or obstructed, except
     for suitable and

                                      D-1
<PAGE>

     approved window drapes or blinds, nor shall any articles be placed on
     window sills.

12.  No awning or other projections shall be attached to, or be visible from,
     the exterior of the Building. No blinds or drapes shall be attached to,
     hung in, or used in connection with any window or door of the Premises
     except in accordance with the standards adopted by Landlord with Landlord's
     prior written approval; in all events where applicable, any blinds, shades,
     or drapes shall be installed on the interior side of windows or doors.

13.  Tenant shall not make, or permit to be made, any unseemly or disturbing
     noises or disturb or interfere with in any manner whatever occupants of the
     Premises or neighboring buildings or premises, or those having business
     with them. Tenant shall not throw anything out of doors or windows, or onto
     public or common areas of the Premises.

14.  Canvassing, soliciting, and peddling in the Premises are prohibited.
     Landlord reserves the right to eject from the Premises any solicitors,
     canvassers, or peddlers and any other persons who, in the judgment of
     Landlord, are annoying or interfering with Tenant's or Landlord's
     operations or who are otherwise undesirable.

15.  Tenant acknowledges that the appearance of its offices exposed to public
     view from outside the Building must be maintained with particular attention
     to orderliness, cleanliness, and an image of professional quality and high
     standards.

16.  Tenant and its employees shall be deemed to have read these rules and
     regulations, and to have agreed to abide by them.

17.  Landlord reserves the right to make such other and further reasonable rules
     and regulations as in Landlord's judgment may be helpful for the safety,
     care, and cleanliness of the Premises and for the preservation of good
     order in the Premises. Tenant agrees to abide by all the rules and
     regulations above stated and any additional reasonable rules and
     regulations which are adopted by Landlord.

                                    INITIALS:
                                    ---------

                                    Landlord: /s/[ILLEGIBLE]
                                              ------------------
                                    Tenant:   /s/[ILLEGIBLE]
                                              ------------------

                                      D-2
<PAGE>

                                  EXHIBIT "E"

                             ENVIRONMENTAL MATTERS
                             ---------------------


A.   Definitions.

     For purposes of this Lease, the following terms have the definitions
ascribed below:

     (1)  "Environmental Laws" shall mean all present and future federal, state,
and local laws, statutes, ordinances, rules, regulations, standards, directives,
interpretations and conditions of approval, all administrative or judicial
orders or decrees, and all guidelines, permits, licenses, approvals, or other
entitlements, or rules of common law, pertaining to the protection of the
environment or human or animal health or safety.

     (2)  "Hazardous Substances" shall mean any chemical, substance, medical, or
other waste, living organism, or combination of same which is or may be
hazardous to the environment or human or animal health or safety due to its
radioactivity, ignitability, corrosivity, reactivity, explosivity, toxicity,
carcinogenicity, mutagenicity, phytotoxicity, infectiousness, or other harmful
or potentially harmful properties or effects. "Hazardous Substances" shall
include, without limitation, petroleum hydrocarbons, including crude oil or any
fraction of same, asbestos, radon, polychlorinated biphenyls (PCBs), methane,
and all substances which now or in the future may be defined as "hazardous
substances," "hazardous wastes," "extremely hazardous wastes," "hazardous
materials," or "toxic substances," or which are otherwise listed, defined or
regulated in any manner pursuant to any Environmental Laws.

     (3)  "Environmental Damages" shall mean all claims, suits, judgments,
damages, losses, penalties, fines, liabilities, encumbrances, liens, costs, and
expenses of whatever kind or nature, contingent or otherwise, matured or
unmatured, foreseeable or unforeseeable, and including, without limitation: (a)
damages for personal injury, or injury to property or natural resources
occurring on or off the Premises, including, without limitation, lost profits,
consequential damages, the cost of demolition and rebuilding, interest and
penalties, and claims brought by or on behalf of employees of Tenant, with
respect to which Tenant waives any immunity to which it may be entitled under
any industrial or workers' compensation laws; (b) fees incurred for the services
of attorneys, consultants, contractors, experts, laboratories, the preparation
of any feasibility studies or reports, or the performance of any investigation,
remediation, removal, abatement, containment, closure, restoration, or
monitoring work required by any federal, state, or local governmental agency or
political subdivision, or reasonably necessary to make full economic use of the
Premises or other property; (c) liability to any third person or governmental
agency to indemnify such person or agency for costs expended or liabilities
incurred in connection with the items referenced in clauses (a) and (b) above;
and (d) diminution of the value of the Premises and damages for loss or
business, restrictions on use, or adverse impacts on marketing rentable or
usable space, or of any amenity, of the Premises.

     (4)  "Manage" or "Management" shall mean any use, generation, storage,
treatment, disposal, transportation, handling, or other management of Hazardous
Substances .

     (5)  "Release" shall mean any accidental or intentional spilling, leaking,
pumping, pouring, emitting, discharging, injecting, escaping, leaching,
migrating, dumping, or disposing into the air, land, surface water, ground

                                      E-1
<PAGE>

water, or the environment (including, without limitation, the abandonment or
discarding of receptacles containing any Hazardous Substances).

B.   Permitted Conditions and Substances.

     Except to the extent expressly permitted in the Schedule of Permitted
Conditions ("Permitted Conditions") and Permitted Substances ("Permitted
Substances") attached as Exhibit "E-1," Tenant shall not generate, use, store,
treat, process, handle, or Release any Hazardous Substances on or about the
Premises. Permitted Conditions may be created or maintained, and Permitted
Substances may be Managed, only in strict compliance with this Lease and all
Environmental Laws. The Schedule of Permitted Conditions and Permitted
Substances shall not be modified in any respect without Landlord's prior written
consent, which may be granted, withheld, or conditioned in Landlord's sole
discretion.

C.   Compliance with Environmental Laws.

     Tenant at its sole cost shall comply with all applicable Environmental
Laws, including, without limitation, procuring and maintaining in effect any
permits or licenses required for Tenant's operations on or about the Premises.
Tenant shall provide Landlord with a photocopy of each such permit or license.
Where applicable Environmental Laws or a permit or license requires a closure
plan, Tenant shall not commence operations or construction of any improvements
until (1) the appropriate governmental authorities, and Landlord, have approved
such closure plan and (2) Tenant has provided evidence satisfactory to Landlord
of its ability to fund the estimated cost of implementing the approved closure
plan.

D.   Storage Tanks.

     Tenant shall not under any circumstances install, use, or operate any
underground storage tanks. Tenant shall not install, use, or operate any
aboveground storage tanks unless specifically approved in advance and in writing
by Landlord. Such approval may be granted, withheld, or conditioned in
Landlord's sole discretion. If Landlord approves the installation, use, or
operation of any aboveground storage tank, Tenant shall be solely responsible
for complying with all requirements which may apply to Landlord as owner of the
Premises, including, without limitation, any financial assurance requirements,
and Tenant shall furnish evidence satisfactory to Landlord of such compliance.
Tenant also shall test the soil for settling and conduct appropriate tests of
the tank and associated piping and equipment at the time of installation to
assure that the tank has been properly installed.

E.   Tenant's Plans.

     Tenant promptly shall provide to Landlord any and all operating, emergency,
contingency, and other plans, procedures or documents pertaining to the
Management or Release of Hazardous Substances on or about the Premises which are
required pursuant to Environmental Laws. In addition, Tenant shall provide to
Landlord:

     (1)  Waste Disposal Plan. Within 30 days after execution of this Lease,
Tenant shall submit to Landlord a written waste disposal plan. Such plan shall
identify, in detail, the anticipated nature, constituents, and average and
maximum monthly quantities of all solid waste Managed at the Premises, whether
or not such waste is or may be a Hazardous Substance. Tenant shall dispose of
all waste that is or may be a Hazardous Substance at off-site

                                      E-2
<PAGE>

locations in accordance with all applicable Environmental Laws, and shall
provide Landlord with a photocopy of any hazardous waste manifest. No waste that
is or may be a Hazardous Substance shall be disposed of in, on, under, or about
the Premises. If Landlord reasonably suspects any waste present at the Premises
to be a Hazardous Substance, Tenant shall sample and analyze such waste in
accordance with applicable Environmental Laws; provided, however, that in the
event any such sample and analysis instigated by Landlord shall fail to indicate
the existence of a Hazardous Substance, Landlord shall pay for such sampling and
analysis. Tenant promptly shall submit a photocopy of the results of such tests
to Landlord.

     (2)  Emergency Plan.  Within 30 days after execution of this Lease, Tenant
shall submit to Landlord a written plan for handling any emergency situations
that reasonably may be anticipated to occur on or about the Premises, including,
without limitation, fires, tsunami, flood, earthquake, explosion, and the
Release of any Hazardous Substances.  At a minimum, the emergency plan shall (a)
comply with all Environmental Laws, (b) contain building evacuation procedures,
Release control and containment procedures for each type of Hazardous Substance
present on the Premises, and (c) include notification procedures and security
measures to limit public access and exposure to any Hazardous Substances.

     (3)  General. Tenant shall not create or maintain the Permitted Conditions,
or introduce Permitted Substances onto the Premises, until Tenant has submitted
to Landlord the waste disposal plans, emergency plans, and any other plans or
similar contingency measures that may be required pursuant to Environmental
Laws. If there is any change in Tenant's operations, or any Permitted Condition
or Permitted Substance is added to Exhibit "E-1," Tenant shall revise and update
such plans and submit them to Landlord. Tenant shall not create the new
Permitted Condition or introduce the new Hazardous Substance onto the Premises
until Tenant has submitted to Landlord such revised and updated plans and
obtained any necessary approvals required pursuant to Environmental Laws. Tenant
at all times shall ensure that its employees are fully trained to execute the
procedures and measures contained in such plans.

F.   Precautionary Measures.

     Tenant, at Tenant's sole cost, shall take all reasonable precautionary
measures ("Precautionary Measures") to prevent structural damage to the Premises
as a result of Tenant's Management of Hazardous Substances.  Such Precautionary
Measures shall include, as necessary, but shall not be limited to, installation
and use of secondary containment facilities; seal coating the floors and roof
structures on a routine basis; continuous monitoring of aboveground and
underground storage tanks; continual monitoring of concrete floors and paved
areas for any pitting or cracks; installation and maintenance of special exhaust
systems or drains for prevention of rusting or corrosion within the Premises;
and, to the extent required by Environmental Laws, maintenance of special waste
water treatment or sewer discharge systems for the lawful discharge of any
Hazardous Substances.  Tenant, at Tenant's sole cost, shall maintain the
Premises in good condition, ordinary wear and tear excepted, and repair any
damage to the Premises resulting directly or indirectly from Tenant's
Management, or the Release or presence of Hazardous Substances in, on, under, or
about the Premises.

                                      E-3
<PAGE>

G.   Reports; Notifications.

     For any year in which any Hazardous Substances have been Managed or
otherwise been present in, on, under, or about the Premises, Tenant shall
provide Landlord with a written report listing the Hazardous Substances which
were present in, on, under, or about the Premises; all Releases of Hazardous
Substances that occurred or were discovered in, on, under, or about the
Premises; Hazardous Substance-related compliance activities; and all manifests,
business plans, consent agreements, or other contracts relating to Hazardous
Substances executed or requested during that time period.  The report shall
include copies of all documents and correspondence related to such activities.

     Tenant shall keep Landlord fully informed at all times regarding all
environmental-related matters affecting Tenant or the Premises.  Tenant shall
give Landlord immediate written notice of (1) any investigation, enforcement,
remediation, or other regulatory action or order taken, issued, or threatened in
connection with the presence, Release, or threatened Release of any Hazardous
Substances in, on, under, or about the Premises or otherwise resulting from the
occupancy, use, or activities of Tenant in, on, under, or about the Premises;
(2) any claims made or threatened by any third party against Tenant, or any
report, notice, or complaint filed or threatened to be filed with any government
agency, in connection with the presence, Release, or threatened Release of any
Hazardous Substance in, on, under, or about the Premises or otherwise resulting
from the occupancy, use, or activities of Tenant in, on, under, or about the
Premises; (3) any Release of Hazardous Substances in, on, under, or about the
Premises, or other property in the vicinity of the Premises, or Tenant's
discovery of any environmental condition which could subject Landlord or the
Premises to any restrictions on ownership, occupancy, transferability, or use of
the Premises; and (4) all incidents or matters as to which Tenant is required to
give notice to any governmental entity pursuant to any Environmental Law.
Tenant shall promptly provide Landlord with photocopies of all claims,
complaints, warnings, materials, reports, technical data, notices,
correspondence, and other information or documents relating to any
environmental-related incidents or matters which are the subject of any notice
required under this Section.

     Tenant acknowledges and agrees that all reporting and warning obligations
required under Environmental Laws are the sole responsibility of Tenant, and
Tenant shall be solely responsible for complying with Environmental Laws
regarding the disclosure of, the Release, threatened Release, presence, or
danger of Hazardous Substances.

H.   Remediation.

     (1)  Environmental Condition.  The generation, presence, use, storage,
treatment, disposal, handling, or Release of any Hazardous Substance in
violation of this Lease, or any Environmental Laws, is referred to as an
"Environmental Condition."  In the event an Environmental Condition exists on or
about the Premises, Tenant shall promptly undertake and diligently complete, at
its sole cost, and in strict compliance with this Lease and all applicable
Environmental Laws, all investigative, corrective, and remedial measures
required to respond to the Environmental Condition.  Such measures shall
include, without limitation, removal and proper disposal of the Hazardous
Substance, and restoration of all land, improvements, and other affected areas
so that, upon completion of the investigation, corrective, or remedial measures,
the Premises and any other areas affected by the Environmental Condition

                                      E-4
<PAGE>

shall be in the same or better condition, character, and quality as before the
Environmental Condition occurred.

     (2)  Landlord's Approval.  Unless an emergency situation exists that
requires immediate action, Tenant shall obtain Landlord's prior written approval
of all contemplated investigative, corrective, or remedial measures.  Such
approval shall not be unreasonably withheld.  Examples of measures subject to
Landlord's prior approval include the selection of any environmental consultant
or contractor, determination of the scope of work and sampling activities to be
performed by the consultant or any contractor, and the form and substance of all
draft reports prepared by any consultant (before such reports are finalized).
                                          ------
Tenant shall provide Landlord with at least three business days' advance notice
of any proposed sampling and, if Landlord requests, Tenant shall split samples
with Landlord.  Tenant shall also promptly provide Landlord with the results of
any test, investigation, or inquiry conducted by or on behalf of Tenant in
connection with the presence or suspected presence of Hazardous Substances on or
about the Premises.  Tenant shall provide Landlord with reasonable advance
notice, and Landlord shall have the right, but not the obligation, to
participate in all oral or written communications with governmental entities
concerning Environmental Conditions on or about the Premises.

     (3)  Landlord's Right to Act. If Tenant fails to comply with this provision
of the Lease, and such failure continues for more than 72 hours after delivery
of written notice from Landlord or a governmental agency, Landlord shall have
the right (but not the obligation), in its sole discretion, and without limiting
any other remedy which may be available to Landlord under this Lease, at law, or
in equity, to respond to the Environmental Condition in any manner it may deem
appropriate. Such right shall include, without limitation, the right to engage
environmental consultants and contractors, conduct any sampling, coring,
testing, digging, drilling, monitoring, and analyses, perform any investigation,
corrective, remedial, or other work required or recommended to correct any
alleged violations, conditions, deficiencies, or hazards noted by any
governmental entity or environmental consultant, and take all steps necessary to
terminate or close any tanks or other facilities. If Landlord performs the
remediation, Tenant shall reimburse Landlord within five business days after
receipt of Landlord's invoice for any amount incurred or expended by Landlord in
connection with such remediation (including consultants', experts' and
attorneys' fees and costs), together with interest at the highest rate permitted
by law, calculated from the date of Landlord's expenditure until paid.

I.   Landlord's Right of Entry; Closure.

     (1)  Right of Entry.  Landlord and its representatives shall have the
right, exercisable by Landlord in its sole discretion, upon reasonable prior
notice to Tenant, to enter the Premises in a manner so as not to unreasonably
interfere with Tenant's occupancy or Use to:  (a) conduct any sampling, testing,
monitoring and analysis for Hazardous Substances, including soil or water
sampling, testing, monitoring, digging and drilling, or structural analyses; (b)
inspect any documents, materials, inventory, financial data, or notices or
correspondence to or from private parties or governmental or regulatory
authorities in connection with Hazardous Substances; (c) review all storage,
use, transportation, and disposal facilities and procedures associated with the
use of Hazardous Substances; and (d) assess the Premises or the Tenant's use of
the Premises (collectively, an "Inspection").  Landlord shall exercise such
right so as to minimize interference with Tenant's activities on the Premises,
to the extent consistent with the full exercise of Landlord's rights.

                                      E-5
<PAGE>

     A representative of Tenant shall be permitted to accompany Landlord and its
representatives during an Inspection.  If the results of an Inspection indicate
that there has been a Release of a Hazardous Substance on or about the Premises,
and Landlord in its reasonable discretion believes, on the basis of the
Inspection, that the Release was caused by an act or omission of Tenant, or
Tenant's employees, agents, sublessees, contractors, representatives, or
invitees, or that Tenant has not complied with this Lease or with Environmental
Laws, Tenant shall pay for the cost of performing the Inspection, including, but
not limited to, the costs of soil or water sampling, testing, or monitoring,
digging and drilling, or structural analysis, and Landlord may pursue all of its
rights and remedies under the Lease, at law, or in equity.


J.   Environmental Tests and Audits.

     Unless otherwise required by Environmental Laws, Tenant shall not perform
or cause to be performed any Hazardous Substances surveys, studies, reports, or
inspections relating to the Premises without obtaining Landlord's advance
written consent.  If, following receipt of Landlord's approval, such activities
are undertaken and the presence of Hazardous Substances in, on, under, or about
the Premises, or likelihood same is confirmed, Tenant shall immediately commence
all necessary remediation, abatement, removal, and cleanup actions in accordance
with that section of this exhibit entitled "Remediation."

K.   Confidentiality.

     (1)  Confidentiality of Environmental Matters. From and after the effective
date of this Lease, Tenant shall exert its best efforts to maintain all matters
relating to Hazardous Substances on the Premises in strict confidence. Except
with the prior written consent of Landlord, and except as may be necessary to
exercise its rights and fulfill its obligations under this Lease, Tenant shall
not disclose to third parties the existence of any matters relating to Hazardous
Substances, and Tenant shall not issue, encourage, or cooperate in the issuance
of, any press releases, media articles, or other public announcements,
including, without limitation, any disclosure with respect to the presence of
any Hazardous Substances at or around the Premises, the terms of this Lease, or
the perceived or known plans and intentions of Landlord with respect to any
matters relating to Hazardous Substances. Nothing within this paragraph shall
preclude Tenant from complying with any laws, regulations, or ordinances
propounded by any court or governmental authority.

     (2)  Confidentiality of Premises Documents and Characteristics.  Tenant
understands that Tenant may be granted certain access rights to certain
confidential information relating to the Premises and Hazardous Substances
during the course of this Lease.  All records, documents, and information with
respect to Hazardous Substances are confidential in nature, including, without
limitation, technical data concerning the Premises, financial, geological
reports, structural reports, and reports regarding Hazardous Substances relating
to the Property, for purposes of this Lease.  Tenant agrees to hold same in
strictest confidence, to not disclose or permit disclosure to any person or
entity, and to not make any unauthorized use of any confidential information
without the prior written consent of Landlord.  Nothing within this paragraph
shall preclude Tenant from complying with any laws, regulations, or ordinances
propounded by any court or governmental authority.

                                      E-6
<PAGE>

     (3)  Property of Landlord.  All confidential information and communications
shall be and remain the property of Landlord, and Tenant shall promptly deliver
any and all information, documents, reports, and correspondence relating to the
Premises to Landlord within five days after termination of this Lease.

L.   Financial Assurances.

     Tenant shall strictly comply with any and all financial assurance
requirements that may be required pursuant to any Environmental Laws for the
occupancy, use, or conduct of activities at and about the Premises.  Upon the
request of Landlord, Tenant shall promptly provide to Landlord photocopies of
documents confirming Tenant's compliance with such requirements. In addition,
Tenant shall provide to Landlord financial assurances in the form of pollution
liability insurance in the amount of $1,000,000.00, which shall assure Landlord
that adequate funds are available to remedy any Environmental Damage or
Environmental Condition which Tenant or the Premises may incur or sustain as a
result of or relating to the Release or Management of Hazardous Substances in,
on, under, or about the Premises.
M.   Termination.

     (1)  Termination of Lease.  Landlord shall have the right to terminate the
Lease in Landlord's sole and absolute discretion in the event that (a) any use
of the Premises by Tenant involves Hazardous Substances in a manner or for a
purpose prohibited by any governmental agency or authority; (b) Tenant has been
required by any lender or governmental authority to take remedial action in
connection with Hazardous Substances at, on, under, or in the vicinity of the
Premises resulting from Tenant's action or use of the Premises (unless Tenant is
diligently seeking compliance with such remedial action); or (c) Tenant is
subject to an enforcement order issued by any governmental authority in
connection with a Hazardous Substance on the Premises (unless Tenant is
diligently seeking compliance with such enforcement order).  Upon termination or
expiration of the Lease, Tenant shall, at its own expense, cause all Hazardous
Substances placed in, on, under, or about the Premises by Tenant or at Tenant's
direction to be removed from the Premises and transported off-site for
treatment, for storage, disposal, or other management in compliance with all
applicable Environmental Laws.

     (2)  Tenant's Post-Termination Obligations.  During any period of time
employed by Tenant after the termination of this Lease to complete the removal
from the Premises or remediation of any such Hazardous Substances, Tenant shall
continue to pay the full rental in accordance with this Lease, which rental
shall be prorated daily at the holdover rate pursuant to the terms of the Lease.
Such payment shall be in addition to any other rights and remedies of Landlord
under this Lease, at law, or in equity.

N.   Assignment and Subletting.

     Notwithstanding any other provisions in this Lease, if (1) any anticipated
use of the Premises by any proposed assignee or subtenant involves the
Management of Hazardous Substances in a manner or for a purpose prohibited by
any governmental agency or authority, or that differs materially from Tenant's
use, (2) Tenant is subject to any claim, enforcement action, action, or
violation relating to Hazardous Substances, or (3) any Hazardous Substances have
been Released in, on, under, or about the Premises, or (4) the proposed assignee
or subtenant has been required by any prior landlord, lender, or governmental
authority to take remedial action in connection with Hazardous

                                      E-7
<PAGE>

Substances contaminating a property, if the contamination resulted from such
party's action or use of the property in question, or (5) the proposed assignee
or subtenant is subject to an enforcement order issued by any governmental
authority in connection with the use, disposal, or storage of any Hazardous
Substances, it shall not be unreasonable for Landlord to withhold its consent to
an assignment or subletting to such proposed assignee or subtenant.

O.   Tenant's Release and Indemnification of Landlord.

     (1)  No Representation by Landlord. Prior to execution and delivery of this
Lease, Tenant has made such inspections and investigations of environmental
conditions in and around the Premises as Tenant desires and deems appropriate.
Tenant, in entering into this Lease, is leasing its Premises "AS IS", subject to
Landlord's indemnity below, in reliance solely on its own inspections and
investigations, and not on any representations, warranties, statements, or other
information from Landlord or its representative, whether express or implied,
except as may be expressly warranted by Landlord in this exhibit.

     (2)  Tenant's Indemnification of Landlord.  In addition to, and without
limiting the scope of, all other indemnities provided by Tenant to Landlord
under this Lease or Environmental Laws, Tenant shall indemnify, defend (with
counsel acceptable to the indemnitees), and hold harmless Landlord and
Landlord's officers, directors, employees, agents, trustees, beneficiaries,
successors, successors in trust, and assigns, from and against any and all
Environmental Damages, directly or indirectly, in whole or in part, arising out
of or in connection with the use or occupancy of the Premises by Tenant or
Tenant's employees, agents, contractors, invitees, or any other person claiming
under Tenant, and related to Hazardous Substances, including, without
limitation, non-compliance with this Lease or any Environmental Laws and the
Release of any Hazardous Substances in, on, under, or about the Premises, and
from the Premises on, to, or into the surrounding lands, air, or water.

     (3)  Landlord's Indemnification of Tenant. Landlord shall indemnify, defend
(with counsel reasonably acceptable to the indemnitees) and hold harmless Tenant
and Tenant's officers, directors, employees, agents, affiliated corporations,
successors, and assigns, from and against any and all Environmental Damages
directly or indirectly, in whole or in part, arising out of or in connection
with Environmental Conditions that 1) existed on or about the Premises as a
result of activities conducted on or near the Premises prior to Tenant's
occupancy of the Premises, or 2) were caused solely by Landlord's gross
negligence or wilful misconduct.

P.   No Shift of Liability.

     Landlord's exercise or failure to exercise the rights granted in this
exhibit to the Lease shall not in any way shift responsibility for Hazardous
Substances or compliance with Environmental Laws from Tenant to Landlord, nor
impose any liability on Landlord.

Q.   Survival.

     The obligations of Tenant under this exhibit to the Lease shall survive any
termination or expiration of this Lease, and any conveyance by Landlord of its
interest in the Premises, and shall continue in full force and effect.

                                      E-8
<PAGE>

APPROVED AS TO FORM:
-------------------

/s/  Margaret C. Fitzgerald
---------------------------
counsel for Tenant

APPROVED AS TO FORM:
-------------------


    /s/ [ILLEGIBLE]
---------------------------
JONES & CANNON,
a professional corporation
440 North Center
Arlington, Texas 76011

                                      E-9
<PAGE>

                                 EXHIBIT "E-1"

                             Permitted Conditions
                             --------------------

--Installation, operation and maintenance of one diesel-fired emergency power
generator and ancillary or related equipment and activities including fuel and
Hazardous Substance storage in above-ground tanks and containers

--Installation, operation and maintenance of lead-acid, nickel-cadmium and any
other type of electrical power storage batteries

--Installation, operation and maintenance of telecommunications, computer,
printing, HVAC, electrical, lighting, satellite and ancillary or related
equipment and activities which may contain or lawfully Release Hazardous
Substances



                             Permitted Substances
                             --------------------


--diesel fuel
--batteries
--ordinary office supplies

                                     E-10
<PAGE>

                                  EXHIBIT "F"

                             OPTION TO EXTEND TERM
                             ---------------------


     This exhibit is attached to and made a part of that certain lease dated
December 21, 1999 by and between THE TRUSTEES UNDER THE WILL AND OF THE ESTATE
OF JAMES CAMPBELL, DECEASED, ACTING IN THEIR FIDUCIARY AND NOT IN THEIR
INDIVIDUAL CAPACITIES ("Landlord"), and EBASEONE CORPORATION ("Tenant"),
covering the property commonly known as 12095 I-45 North, Houston, Texas 77060
(the "Premises").

                           I.  OPTION TO EXTEND TERM

     Landlord hereby grants to Tenant one Option (the "Option") to extend the
Term for an additional term of five years (the "Extension"), on the same terms,
conditions, and covenants set forth in the Lease, except as provided below.  The
Option shall be exercised only by written notice delivered to Landlord not more
than 12 months nor less than six months prior to the expiration of the Term.  If
Tenant fails to deliver to Landlord written notice of the exercise of the Option
within the prescribed time period, the Option shall lapse, and there shall be no
further right of Tenant to extend the Term.  The Option shall be exercisable by
Tenant on the express condition that, at the time of the exercise, and at all
times prior to the commencement of the Extension, Tenant shall not be in default
under any of the provisions of the Lease.  The foregoing Option is personal to
Tenant and may not be exercised by any assignee or subtenant of Tenant.

                           II.  CALCULATION OF RENT

                         Fair Rental Value Adjustment
                         ----------------------------

     The Base Rent shall be increased on the first day of the Extension to the
"Fair Rental Value of the Premises" (as defined below), determined in the
following manner:

     a.  Landlord and Tenant shall endeavor in good faith upon Tenant's
exercise of the Option to agree upon the Fair Rental Value of the Premises.  If
Landlord and Tenant have not been able to agree on the Fair Rental Value of the
Premises within 30 days after Tenant's exercise of the Option, the Base Rent for
the Extension shall be determined as follows:  within 45 days following the
exercise of the Option, Landlord and Tenant shall endeavor in good faith to
agree upon a single appraiser.  If Landlord and Tenant are unable to agree upon
a single appraiser within said 45 day period, each shall then, by written notice
to the other, within ten days after said 45 day period, appoint one appraiser.
Within ten days after the two appraisers are appointed, the two appointed
appraisers shall appoint a third appraiser.  If either Landlord or Tenant fails
to appoint its respective appraiser within the prescribed time period, the
single appraiser appointed shall determine the fair rental value of the
property.  If the two appointed appraisers fail to agree on the third appraiser,
he or she shall be appointed by the then president of the Houston Board of
Realtors. Each party shall bear the cost of the appraiser appointed by it, and
the parties shall share equally the cost of the third appraiser.

     b.  The term "Fair Rental Value of the Premises" shall mean the rent that a
ready and willing tenant would pay, at the time of the commencement of the
Extension, as monthly Base Rent to a ready and willing lessor of property
comparable to the Premises, if such property were exposed for lease on the open
market for a reasonable period of time, and taking into account all of the
purposes for which such property may be used, and not just the use proposed to
be made of the property by Tenant.  The Fair Rental Value of the Premises

                                      F-1
<PAGE>

shall be the average of the two of the three appraisals which are closest in
amount, and the third appraisal shall be disregarded. In no event shall the Base
Rent be reduced by reason of such computation. If the Fair Rental Value of the
Premises is not determined prior to the commencement of the Extension, then
Tenant shall continue to pay to Landlord the Base Rent applicable to the
Premises immediately prior to the Extension, until the Fair Rental Value of the
Premises is determined, and when it is determined, Tenant shall pay to Landlord
within ten days after receipt of written notice the difference between the Base
Rent actually paid by Tenant to Landlord and the new Base Rent determined under
this provision.


                                         INITIALS:
                                         ---------

                                         Landlord:     /s/ [ILLEGIBLE]
                                                    ------------------------

                                         Tenant:      /s/ [ILLEGIBLE]
                                                 ---------------------------


approved as to form:
--------------------


/s/  Margaret C. Fitzgerald
---------------------------
counsel for Tenant

approved as to form:
-------------------

     /s/ [ILLEGIBLE]
---------------------------
JONES & CANNON,
a professional corporation
440 North Center
Arlington, Texas 76011

                                      F-2
<PAGE>

                                  EXHIBIT "G"

                        TELECOMMUNICATION RECEIVER AND
                      TRANSMISSION EQUIPMENT/USE OF ROOF
                      ----------------------------------


                              Grant of Permission
                              -------------------

     Subject to the terms below, Landlord hereby grants Tenant the right to
utilize a portion of the roof of the Project above the Premises solely for the
installation, operation, and maintenance of telecommunication receiver and
transmission equipment ("Satellite Equipment").

                       Landlord's Prior Written Approval
                       ---------------------------------

     Tenant shall not install or operate any Satellite Equipment until and
unless it receives the prior written approval of Landlord, which approval shall
not be unreasonably withheld.  Landlord shall approve or reject the proposed
installation and operation of the Satellite Equipment within ten business days
after Tenant submits 1) plans and specifications for the proposed installation
of the Satellite Equipment, 2) photocopies of all required governmental and
quasi-governmental permits, licenses, and authorizations, and 3) all
certificates of insurance as required pursuant to the terms of the Lease.

     Landlord shall have the right to reasonably disapprove any such information
or plans,  and such disapproval shall negate any right of Tenant to install
Satellite Equipment upon the Project.  Notwithstanding anything within this
provision to the contrary, Tenant shall not permit or cause any Satellite
Equipment, or the installation and/or operation of any Satellite Equipment, to
damage the structural integrity of the Project, penetrate or damage the roof of
the Project, interfere with any service provided by Landlord to any tenant of
the Project, reduce the amount of leasable space in the Project, detract from
the aesthetic value of the Project, or invalidate any applicable roof warranty.

               Installation and Operation of Satellite Equipment
               -------------------------------------------------

     Tenant covenants and agrees that neither Tenant nor its agents will cause
any damage to the roof of the Project, or any part of the common area of the
Project, during the installation and/or operation of any Satellite Equipment.
If any such damage is caused,  Tenant shall be responsible for all damages which
may occur to the roof of the Project or to the Project.

                                   Insurance
                                   ---------

     During any time that Tenant utilizes Satellite Equipment, Tenant shall
maintain insurance coverage as required in article X of the Lease, and such
coverage shall reference and include the use of the area of the roof of the
Project utilized for the Satellite Equipment,  and Tenant's use of the Satellite
Equipment shall be so noted in the certificate of insurance provided to Landlord
pursuant to the terms of the Lease.  Prior to Tenant's installation and
operation of any Satellite Equipment, and throughout the term of the Lease,
Tenant shall provide Landlord with evidence of such additional insurance
satisfactory to Landlord, in its sole discretion, that Landlord deems reasonably
necessary for the installation and operation of the Satellite Equipment.  All
such policies shall name Landlord and such other individuals or entities as
Landlord may from time to time designate as "additional insureds."
<PAGE>

                       Termination and Relocation Rights
                       ---------------------------------

     Landlord may, in its sole judgment and discretion, terminate Tenant's right
to install Satellite Equipment upon 24 hours' written notice, in the event that
the Satellite Equipment is 1) causing physical damage to the structural
integrity of the Project, or 2) is interfering with the safety, access, or use
of any part of the common area of the Project, or 3) invalidates any applicable
roof warranty for the Project.

     Landlord may, in its sole judgment and discretion, require Tenant, upon 15
days' prior written notice, to relocate the Satellite Equipment to another
location upon the roof of the Project as may be designated by Landlord.  Any
such relocation cost shall be at Landlord's sole expense.

                        Removal of Satellite Equipment
                        ------------------------------

     Upon revocation of the right granted by this exhibit, or upon the
Termination Date or earlier termination of the Lease, Tenant shall be required
to remove the Satellite Equipment from the Project at Tenant's sole cost and
expense.  Tenant shall leave the portion of the roof of the Project where the
Satellite Equipment was located in good order and repair, and Tenant shall be
responsible for repairing the roof of the Project, and for all damages that may
occur to the roof or the Project caused by the installation, operation, or
removal of the Satellite Equipment.

     In the event that Tenant does not remove the Satellite Equipment when
required, Tenant hereby authorizes Landlord to remove and dispose of the
Satellite Equipment, and Tenant expressly authorizes Landlord to charge Tenant
for all costs and expenses incurred by Landlord as a result of such removal and
disposition.  Tenant agrees that Landlord shall not be liable in any manner for
any such property disposed of or removed by Landlord.

                      Licenses, Permits, Laws, and Rules
                      ----------------------------------

     Tenant shall secure at its sole cost and expense from the proper
governmental authorities all licenses or permits required by law for the
installation, maintenance, or operation of any Satellite Dish.  Tenant shall at
its own expense promptly observe and comply with all laws, rules, or
requirements of all federal, state, or local governmental units or agencies, as
such laws, rules, or requirements may relate to the installation or operation of
Satellite Equipment.   Tenant shall pay any fines, penalties, damages, or costs
arising directly or indirectly from Tenant's failure to observe or comply with
said laws, rules, or regulations.

                          Release and Indemnification
                          ---------------------------

     Tenant hereby waives all claims against Landlord for damage upon or about
the Premises or the Project arising from any use or operation of the Satellite
Equipment, and Tenant hereby agrees that the provisions of article XII shall
apply to any usage of the roof of the Project by Tenant for utilization of
Satellite Equipment.

                                  Emergencies
                                  -----------

     In the event of any emergency affecting the Project, Landlord shall have
the right at any such time to take any and all  reasonable measures, including
inspection, repair, or removal of any Satellite Equipment, as may be necessary
or desirable for the safety, protection, or preservation of the Premises or the
Project, or in order to comply will all laws, orders, or requirements of
governmental or other authorities.  Landlord's rights pursuant to this

                                      G-2
<PAGE>

paragraph shall not otherwise diminish the rights granted to Tenant under this
exhibit.

                                      INITIALS:
                                      ---------

                                      Landlord:     /s/ [ILLEGIBLE]
                                                 ------------------------

                                      Tenant:     /s/ [ILLEGIBLE]
                                              ---------------------------

APPROVED AS TO FORM:
--------------------


/s/  Margaret C. Fitzgerald
-----------------------------
counsel for Tenant

APPROVED AS TO FORM:
-------------------


     /s/ [ILLEGIBLE]
 ---------------------------
JONES & CANNON,
a professional corporation
440 North Center
Arlington, Texas 76011

                                      G-3