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                                                                    EXHIBIT 10.7



                                 LEASE AGREEMENT

       THIS LEASE AGREEMENT (the "Lease"), made in multiple copies and entered
into between American Southwest Properties, Inc., an Oklahoma corporation, (the
"Landlord"), and MPSI System Inc., a Delaware corporation (the "Tenant");

                                   WITNESSETH:

       That Landlord in consideration of the covenants and agreements to be
performed by Tenant and upon the terms and conditions hereinafter stated does
hereby lease, demise and let unto Tenant and Tenant does hereby let and accept
from Landlord the premises described in Exhibit "A" (the "Demised Premises"),
complete with the item of work and materials required. if any, under the term of
a certain work letter executed between Landlord and tenant attached hereto as
Exhibit "B" in the building known as the Southpark Building (the "Building")
together with outdoor, non-exclusive, surface automobile parking adjacent to the
Building at a ratio of one parking space per 250 rentable square fed ("RSF") in
the Demised Premises, from time to time, all on that certain tract or parcel of
land located, lying and being situate in Tulsa County, State of Oklahoma, more 
particularly described as follows:

               Lot One (1), Block Three (3), SOUTHPARK CENTER (Block One (1)
               Lots One (1) through Four (4), Block Two (2) and Lot One (1), 
               Block Three (3)), an Addition to the City of Tulsa, according to 
               the recorded Plat thereof (the "Land");

          TO HAVE AND TO HOLD the Demised Premises unto the Tenant, its duly
approved successors and assigns, for sixty-two (62) consecutive months (the
%ease Term") commencing the first day of the mouth after (1) the date Tenant
actually takes possession of the Demised Promises, in whole or in part, i.e.,
for occupancy or use, or (2) ninety (90) days after the date on which the Lease
is fully executed by the Landlord and Tenant, whichever date occurs first (the
"Commencement Date"), and ending, at midnight local time on the last day of the
sixty-second (62nd) month after the Commencement Date (the "Expiration Due);
PROVIDED, however, Tenant shall be permitted access to the Demised Premises
before the Commencement Date once this Lease is in force at all reasonable times
and under reasonable conditions for purposes of construction and installation of
leasehold improvements and furnishing the same. By occupying the Demised
Premises, Tenant shaft be deemed to have accepted them as suitable for an
purposes and to have acknowledged they comply fully with Landlord's obligations
hereunder. For purposes of this paragraph, occupancy or occupying shall not
include construction prior to move in to the Demised Premises. Landlord hereby
waives payment of rent covering any period prior to the tendering of possession
to Tenant hereunder. The Lease shall be subject to the following terms and
conditions:

       1. RENT. Tenant promises to pay Landlord at Landlord's place of business,
in advance and without further demand or set off, the sum of Two Million Six
Hundred Thirty-Seven Thousand Four Hundred Twenty-Four and 201100 Dollars
($2,637,424.20) as and for


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minimum rent for the entire Lean Term in monthly installments payable as
follows: A. No rent shall be due and payable during the first two months of the
Lease Term;

         B. Commencing the third month of the Lease Term and on like date of
each of the next succeeding months through and including the 14th month thereof
the monthly rent is $41,698.90 per month ($9.19 per RSFX 54,436 RSF divided by
12);

         C. Commencing the 15th month of the Lease Term and on like date of each
of the next succeeding months through and including the 26th mouth thereof the
monthly rent is $42,922.99 per mouth ($9.44 per RSF X 54,436 RSF divided by 12);

         D. Commencing the 27th month of the Lease Term and on like date of each
of the next succeeding months through and including the 38th month thereof the
monthly rent is $43,957.07 per month ($9.69 per RSF X 54,436 RSF -4-12);

         E. Commencing the 39th month of the Lease Term and on like date of each
of the next succeeding months through and including the 50th month thereof the
monthly rent is $45,091.15 per month ($9.94 per RSF X 54,436 RSF - 12); and

         F. Commencing the 51st month of the Lease Term and on like date of each
of the next succeeding months through and including the 62nd and final month
thereof the monthly rent is $46,225.24 per month ($10.19 per RSF X 54,436 RSF
divided by 12) until all minimum rent is My paid.

         Further, if this Lease be renewed, pursuant to the provisions of
Paragraph 34, infra, then in such event, commencing on the first day of the
Renewal Term, and on like date of each of the succeeding months through and
including the 12th and final month thereof the monthly rent payable to Landlord
shall be determined, as follows: $10.70 per RSF X 54,436 RSF divided by 12.

         All installments of said rent shall be due and payable, without demand
or setoff on or before the first day of each calendar month during the Lease
Term. Rent for any fractional month at the beginning or end of the LEASE, Term
shall be prorated. A security deposit of Forty-One Thousand Six Hundred
Eighty-Eight and 90/100 Dollars ($41,689.00) shall be payable to Landlord in
addition to the monthly minimum, rent installment due January 1, 1999. The
security deposit shall be held by Landlord as security for the performance by
Tenant of Tenant's covenants and obligations under this Lease, it being
expressly understood that such deposit shall not be considered an advance
payment of rental or a measure of Landlord's damages in case of default by
Tenant. Upon the occurrence of any event of default by Tenant, Landlord may,
from time to time, without prejudice to, any other damage, injury expense or
liability caused to Landlord deduct said amount from the security deposit and
demand repayment of the amount so applied in order to restore the security
deposit to its original amount. If Tenant is not then in default hereunder, any
remaining balance of such deposit shall be returned by Landlord to Tenant upon
termination of this Lease. If Landlord transfers its interest in the Demised
Premises, Landlord shall assign the security deposit to the transferee and
thereafter shall have no further liability for the return of such security
deposit.

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        In the event Tenant fails to pay any installment of rent or other
incurred expense hereunder within five (5) days of the due date, to help defray
the additional cost to Landlord for processing such late payments Tenant shall
pay to Landlord on demand a late charge in an amount equal to five percent (5%)
Of such installment. The provision for such late charge shall be in addition to
all of Landlord's other rights and remedies hereunder or at law, equity or both
and shall not be construed as liquidated damages or as limiting Landlord's
remedies in any manner.

       2. USE. The Demised Premises shall be used and occupied by Tenant only as
general office space. Tenant shall not use, or permit to be used, the Demised
Premises for any other purpose. Tenant will not occupy or use, nor permit the
occupation or use of any portion of the Demised Premises for any business or
purpose which is unlawful in part or in whole or deemed to be disreputable in
any manner or extra hazardous on account of fire, nor permit anything to be done
which will in any way increase the rate of fire insurance on the Building or its
contents, and in the event that, there shall be any increase in the rate of
insurance on the Building or contents created by Tenant's ads or conduct of
business then such acts shall be deemed to be an event of default hereunder and
Tenant hereby agrees to pay the amount of such increase on demand, and
acceptance of such payment shall not constitute a waiver of any of Landlord's
rights hereunder.

         3. LANDLORD'S OBLIGATIONS. The Landlord shall be responsible for the
following items:

          A. Furnishing utility services such as electricity, water and sewer,
natural gas, and telephone services at the points of supply provided for general
use of tenants of the Building; heated and refrigerated air conditioning in
season, at such times as Landlord normally furnishes these services to all
tenants of the Building, and at such temperatures and in such amounts as are
considered standard for comparable office buildings in Tulsa, Oklahoma divided
by including without limitation, janitorial services (5 day per week the
schedule for which is attached hereto as Exhibit "C"); elevator service; and
electric service in the manner and to the extent deemed standard for comparable
office buildings in Tulsa, Oklahoma. The failure, to any went to furnish, or any
stoppage of these defined services, resulting from any cause, shall not render
Landlord liable in any respect for damages to person, property or business, nor
be construed as an eviction of Tenant or work as at) abatement of rent (unless
said interruption continues for fifteen (15) consecutive days after notice in
writing has been received by Landlord, in which event rent shall abate as of the
date of the interruption), nor relieve Tenant from fulfillment of any covenant
or agreement thereof "Should any equipment or machinery furnished by Landlord
break down, or for any cause cease to function property, Landlord shall use
reasonable diligence to repair same promptly, but Tenant shall have no claim for
rebate of rent (unless said interruption continues for fifteen (15) consecutive
days in which event rent shall abate as of the date of the interruption) or
damages on account of any interruptions in service occasioned thereby or
resulting therefrom. Tenant shall pay to Landlord on demand such charges as
Landlord may reasonably prescribe for any extraordinary electric service
required by Tenant. Landlord agrees that all equipment required to be installed
by Landlord will be in good working condition on the Commencement Date. General
ad valorem taxes and special assessments, if



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any, property insurance (fire and extended coverage insurance) on the Building
itself, general maintenance and management expense shall be the Landlord's
expense, subject to the right to recover a part of the basic costs pursuant to
Section 15 hereof. Landlord agrees that the temperature variance in the Demised
Premises shall not exceed 85 degrees F. nor fall below 55 degrees F. during
Non-Operating Hours of the Building. Landlord agrees to be responsible for
general maintenance of the Building and surrounding grounds including, but not
limited to, trash removal, mowing and snow removal on sidewalks and parking
areas.

       B. Except when the Tenant is observing National or State holidays in the
ordinary course of its business, the Building shall be open for business between
7:00 o'clock A.M. and 6:00 o'clock P.M., Monday through Friday and 8:00 o'clock
A.M. until 1:00 o'clock P.M. on Saturdays (the "Operating Hours"). The HVAC, gas
and electrical utility charges for the Building shall be the obligation of the
Landlord during Operating Hours of the Building.

       Should the Tenant require HVAC, gas and/or electricity other than during
Operating Hours then, in that event, the Landlord shall provide such additional
services to the Demised Premises upon Tenant's prior request and Tenant shall
pay Landlord for such services within fifteen (15) days of receipt of an invoice
therefor at an hourly rate reasonably determined by Landlord and agreed to by
Tenant within ninety (90) days after the Tenant's move in (the "Hourly Rate"
charged for use of utilities during non-operating hours). After the first Lease
Year, Landlord shall only have the right to adjust the hourly rate once a year
at the time the Landlord adjusts Tenant's Operating Expenses. Any adjustment to
the hourly rate shall be determined by professional means or such other means as
may produce objective, verifiable evidence of said increased cost. Tenant and/or
Landlord may, with the Landlord's prior written consent as to type, model, make
and cost, elect to purchase and install an electrical and gas measuring device
to record the actual times these services are used by the Tenant before and
after Operating Hours of the Building. In such event, Tenant shall be
responsible for the first $10,000 cost to purchase and install such device and
the Landlord shall be responsible for the excess. In the event such system
benefits the entire building, Tenant's share of said cost shall be calculated on
a pro rata basis not to exceed $10,000. Should the device not be purchased or
installed, or if installed, should it fail to become operative or in disrepair
for any reason, then, in either event, the Landlord shall be entitled to
professionally estimate all other hourly charges and bill the same to the Tenant
with equal force and effect.

       C. Landlord shall pay Tenant a relocation allowance of $81,654 ($1.50 X
54,436 RSF) payable in cash within 90 days after the Lease is executed by
Landlord and Tenant.

       D. Landlord shall maintain a minimum of 10,000 rentable square feet
("RSF") in the Building contiguous to the Demised Premises (previously
identified as first floor - Section "L" West and N/2 Section H, as defined in
Exhibit "E") for a period of two (2) years from and after the Rent Commencement
Date for potential use by Tenant should it elect to expand its offices. Tenant
shall not be charged for the 1,922 RSF hallway, although included within the
aforementioned 10,000 RSF (herein "Expansion Area"). Expansion Area shall be
held by the Landlord without additional charge to Tenant. Should Tenant elect to
exercise its options to rent any or all of Expansion Area, Tenant shall give
Landlord sixty (60) days notice in writing.



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Rent shall commence after the sixty (60) day period or on the date of occupancy
or use thereof, whichever occurs first, at the same rate per rentable square
foot then applicable. The Lease Term herein mentioned shall apply equally to the
expansion space and any and all tenant improvement allowances shall apply
equally to the Expansion Area and any and all tenant improvement allowances
shall be reduced and prorated in ratio to the Lease Term remaining as of the
date rent shall commence. The Expansion Area shall be made available coterminous
with the terms of the original lease. If Tenant elects to exercise its expansion
option during the first two (2) years of the lease term, Tenant must first
expand into the 10,000 square feet reserved Expansion Area, before expanding
into additional blocks of space within the building.

       During the Lease Term, 823 square feet of "as is" storage space is
available to Tenant at no charge within the Demised Premises, which is in
addition to the 54,436 square feet of rentable space. The location of this 823
square feet is shown on Exhibit A. In addition, Landlord will make available at
no charge to Tenant, 1700 square feet of "as is" storage space within the
building, during the Lease, contingent upon at least 1700 square feet remaining
unoccupied by another tenant within the building. During the first two (2) years
of the Lease Term, the 1700 square feet of "as is" storage space shall be
located within the unoccupied portion of the 10,000 square feet of reserved
Expansion Space described above. After the first two (2) years of the Lease Term
(or during the first two (2) years of the Lease Term, should tenant elect to
fully occupy the reserved Expansion Space described above), the location of the
1700 square feet of "as is" storage space shall be determined at Landlord's
sole discretion. Should Landlord lease Tenant's storage space to a third party,
Tenant shall vacate the space within thirty (30) days of written notice from
Landlord (or prior to the second year, if Tenant exercises its Expansion
Option).

       E. Landlord shall maintain a minimum of 10% of total air volume intake of
outside air in the Building's HVAC system


       F. Landlord shall have Tenant's carpeted areas professionally cleaned one
time per year upon five days verbal notice from Tenant to Landlord, at
Landlord's sole expense.

       4. TENANT'S REPAIRS AND ALTERATIONS. All existing fixtures, equipment,
HVAC and other improvements in the Demised Premises shall remain in-place for
Tenant's use if applicable to Tenant's plans at no additional charge to Tenant.
Tenant shall have the right to perform its own construction management,
including, but not limited to selection of contractors pre-qualified and
approved in writing by Landlord. There shall be no additional Landlord mark-up
for construction costs or construction management. Landlord has the right to
approve Tenant's plans, PROVIDED that Tenant is no way relieved of its
responsibility to maintain the building and structure integrity. Tenant shall
pay all design and engineering fees associated with Tenant's work. Tenant may
amortize the cost of additional improvements over and above the allowance stated
in Paragraph 1.G. of Exhibit B (Work Letter); however, not to exceed a maximum
of $12.00 per square foot by adding to the minimum rent payments using a 9.5%
interest rate. Tenant shall not be required to remove its cabling and telephone
lines at the expiration of the Lease.



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         Tenant shall not in any manner deface, damage or injure the Building,
or any part thereof and shall pay the cost of repairing any damage or injury
done to the Building or any part thereof by Tenant or Tenant's agents,
contractors, employees and invitees. Tenant shall take good care of the Demised
Premises and keep them free from waste and nuisance of any kind. Tenant agrees
to keep the Demised Premises, including all fixtures installed by Tenant and any
interior plate glass, in good condition and make all necessary repairs. At the
end or other termination of this Lease, Tenant shall deliver up the Demised
Premises with all improvements located thereon, except as provided in this
paragraph, in good repair and condition, reasonable wear and tear accepted.
Except for non-structural alterations costing less than $10,000 for each such
alteration, Tenant shall not make or allow to be made any alterations or
physical additions in or to the Demised Premises without the prior written
consent of Landlord. Such improvements shall be delivered up to Landlord with
the Demised Premises. All furniture and moveable trade fixtures installed by
Tenant may be removed by Tenant at the termination of this Lease if Tenant so
elects and shall be removed if Landlord so elects. All such removals and
restoration shall be accomplished in a good and workmanlike manner so as not to
damage the structure or structural qualities of the Building. If the removal of
trade or other fixtures as Tenant shall be entitled to remove at the end of the
Lease Term and Renewal Term, as applicable, blemishes or otherwise damages the
walls, floors, ceiling and other parts of the Demised Premises, then, Tenant
shall be obliged to promptly repair said damage, ordinary wear and tear
excepted.

       The sufferance or commission of waste or filing of mechanic's or
materialmens' or laborer's liens on the Building Land shall constitute an event
of default by the Tenant, and failure of Tenant to secure release and discharge
of such liens, or to provide sufficient security acceptable to Landlord to
protect Landlord against said liens after thirty (30) days written notice to
Tenant, shall constitute a default under the Lease, for which Landlord may
exercise any remedy at law or in equity available to obtain relief therefrom.

         5. ASSIGNMENT AND SUBLETTING. Tenant shall not assign this Lease, or
allow same to be assigned by operation of law or otherwise, or sublet the
Demised Premises or any part thereof without the prior written consent of
Landlord, which consent shall not be unreasonably withheld or delayed. Landlord
shall have the right to transfer and assign, in whole or in part, any of its
rights under this Lease, and in the Building and Property, and to the extent
that such assignee assumes Landlord's obligations hereunder, Landlord shall by
virtue of such assignment be released from such obligations occurring after the
effective date of the assignment. No assignment or subletting of this Lease or
any part thereof by Tenant, shall operate to release Tenant from its obligations
under this Lease. So long as Tenant or any Related Entity (hereinafter defined),
is the Tenant, Tenant shall have the right, without the consent or approval of
Landlord, to: (a) assign its interest in the lease (i) to any corporation or
other entity which is a successor to Tenant either by merger or consolidation,
or (ii) to a purchaser of all or substantially all of Tenant's assets, or (iii)
to a corporation or other entity which shall directly or indirectly control, be
under control of, or be under common control with a Related Entity. For purposes
hereof, control shall be deemed to mean the direct or indirect




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ownership of more than fifty percent of the outstanding voting stock of a
corporation or other majority equity and controlling interest if not a
corporation.

       6. MAINTENANCE. Tenant shall maintain the Demised Premises in a clean and
healthful condition, and except as provided in Section 24 of this Lease, comply
with all laws, ordinances, orders, rules, and regulations (state, federal,
municipal, and other agencies or bodies having any jurisdiction thereof) with
reference to use, condition, or occupancy of the Demised Premises.

       7. LIABILITY AND INSURANCE. Landlord shall not be liable for and Tenant
will save, defend, indemnify, and hold Landlord harmless from any loss,
liability, costs and expenses, including attorneys fees, arising out of any
claim for bodily injury or property damage on or about the Demised Premises due
to the alleged negligence or misconduct or breach of this Lease by Tenant, its
agents, contractors, employees, invitees or by any other person entering the
Demised Premises, the Building or Land under express or implied invitation of
Tenant or arising out of Tenant's agents, contractors, employees, invitees or
any person entering upon the Property in whole or in part because of Tenant's
use of the Demised Premises for any damage to persons or property due to
condition, design or defect in the Demised Premises or its mechanical systems
which may exist or occur, and Tenant assumes all risks of damage to such persons
or property, Landlord shall not be liable or responsible for any loss or damage
to any property or person occasioned by theft fire, act of God, public enemy,
injunction, riot, strike, war, court order, requisition or order of governmental
body or authority, or other matter beyond the control of Landlord, or for any
injury or damage or inconvenience, which may arise through repair or alteration
of any part of the Building, or failure to make repairs, or from any cause
whatever except Landlord's willful acts or negligence.

       TENANT'S INSURANCE.

       Tenant, at its expense, shall maintain in force during the Lease Term:

       (1) comprehensive general public liability insurance, which shall include
coverage for personal injury, contractual liability, broad form property damage,
products/completed operations, independent contractors, bodily injury (including
death), and property damage, all on an occurrence basis with respect to the
business carried on, in or from the Demised Premises and Tenant's use and
occupancy of the Demised Premises with coverage for any one occurrence or claim
of not less than $1,000,000.

       (2) fire and extended coverage insurance for the replacement value of
Tenant's property (including fixtures, leasehold improvements and equipment
which Tenant is required to replace under this Lease) in the event of loss,
damage or destruction.

       All insurance required to be maintained by Tenant shall be on terms and
with insurers reasonably acceptable to Landlord.  Each policy shall contain a
waiver by the insurer of any rights of subrogation or indemnity or any other
claim as provided herein. These policies shall name Landlord as an additional
insured.



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       Such insurance shall contain a clause that the policy will not lapse, be
canceled or be materially changed, except after not less than 30 days' prior
written notice to Landlord of the intended change, lapse or cancellation. Tenant
shall furnish to Landlord, if and whenever requested by it, certificates or
other evidences acceptable to Landlord as to the insurance from time to time
maintained by Tenant and the renewal or continuation in force of such insurance.

       Landlord at all times during the term of this Lease and any other period
of occupancy of the Premises by Tenant shall provide and maintain, at Landlord's
expense, comprehensive fire insurance with extended coverage insuring the
Building, providing such level of coverage and insuring against such risks as
are customarily maintained with respect to comparable Buildings in the market in
which the Premises are located.

       Each party hereto hereby waives any and all claims for recovery which
such party or anyone claiming through such party may have against the other
party hereto (or such other party's officers, agents or employees) for or with
respect to any loss of or damage to such waiving party's property which is
insured under valid insurance policies, to the extent of any recovery actually
collectible under such insurance policies, whether or not such loss or damage
caused by the negligence of such other party or such other party's agents,
employees, subtenants, concessionaires or licensees or of any other person or
persons for whose actions such other party may be responsible or liable.
Landlord and Tenant each agree to obtain from the insurance companies providing
its insurance applicable hereto permission to allow Landlord and Tenant to waive
their respective insurance companies' rights of subrogation. Landlord and Tenant
shall each provide to the other written proof of the waiver of said claims by
said insurance companies.

       8. RULES AND REGULATIONS. Tenant and Tenant's agents, contractors,
employees, visitors and invitees shall comply fully with all requirements of the
rules of the Building, a copy of which is attached hereto as Exhibit "D" and
made a part hereof as though fully set out herein. Landlord shall at all times
have the right to change such rules and regulations or to amend them in such
reasonable manner as may be deemed advisable for safety care, and cleanliness of
the Building and for preservation of good order therein, all of which rules and
regulations, changes, and amendments, shall apply equally to all tenants and
will be furnished to Tenant in writing and shall be carried out and observed by
Tenant. Tenant shall further be responsible for the compliance with such rules
and regulations by the employees, servants, agents, contractors, visitors and
invitees of Tenant. In the event of a conflict between the rules and regulations
and this Lease, the provisions of the Lease shall control.

       9. INSPECTION. Landlord, or its officers, agents, contractors and
representatives, shall have the right to enter into and upon any and all parts
of the Demised Premises, upon prior reasonable notice and approval of tenant
(except in the event of an emergency), (a) at all reasonable hours to inspect
same or clean or make repairs or alterations or additions as Landlord may deem
necessary, or (b) during business hours to show the Demised Premises to
prospective tenants, purchasers or lenders, and Tenant shall not be entitled to
any abatement or reduction of rent by reason thereof



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       10. CONDUCT OF BUSINESS. Tenants shall conduct its business, and control
its agents, contractors, employees, visitors so as not to create any nuisance,
or interfere with, annoy or disturb other tenants or Landlord in the management
of the Building.

       11. CONDEMNATION. If the Demised Premises are taken or condemned in whole
or part for public purposes, then this Lease shall at the option of Landlord or
Tenant, to be exercised by written notice given to the other within thirty (30)
days after the date of such taking forthwith cease and terminate.

       12. FIRE AND OTHER CASUALTY. In the event that the Building should be
totally destroyed, without limitation, by fire or other casualty, or should be
so damaged that rebuilding or repairs cannot be completed within one hundred
eighty (180) days after the date of such casualty, either Tenant or Landlord may
at its option terminate this Lease, to be exercised within thirty (30) days
after the date of such casualty. In the event this Lease is not so terminated,
rent shall be abated during the unexpired portion of this Lease effective with
the date of such damage, and Landlord may proceed to rebuild and repair the
Building and the Demised Premises, except that Landlord shall not be required to
rebuild, repair or replace any part of the partitions, fixtures, and other
improvements which may have been placed by Tenant or other tenants within the
Building. In the event the Building should be damaged by fire or other casualty,
but only to such extent that rebuilding or repair can be completed within one
hundred eighty (180) days after the date of such casualty, or if the casualty
should be more serious but neither Landlord or Tenant elect to terminate this
Lease, in either such event Landlord shall within forty (40) days after the date
of such casualty commence to rebuild or repair the Building and shall proceed
with reasonable diligence to restore the Building to substantially the same
condition in which it was immediately prior to the happening of the casualty,
except that Landlord shall not be required to rebuild repair or replace any part
of the partitions, fixtures, and other improvements which may have been placed
by Tenant or other tenants within the Building. Landlord shall allow Tenant a
fair diminution of rent during the time the Demised Premises are unfit for
occupancy. Any insurance which may be collected by Landlord or Tenant against
loss or casualty to the Building or to the Demised Premises shall be for the
sole benefit of the party, carrying such insurance and under its sole control.
Notwithstanding any of the foregoing to the contrary, neither Landlord nor
Tenant shall be required to continue under this Lease if the Demised Premises
have been damaged to such an extent that Tenant has been required to vacate all
or a substantial portion of the Demised Premises and at the time such casualty
occurred, less than twelve (12) months remain on the Term.

       13. HOLDING OVER. Should Tenant, or any of its successors in interest,
hold over the Demised Premises, or any part thereof after the expiration of the
Lease Term or Renewal Term, as the case may be, unless otherwise agreed in
writing, such holding over shall constitute and be construed as a tenancy at
sufferance only, at a rental equal to the rent paid for the last month of the
Term, plus fifty percent (50%) of such rent. The inclusion of the preceding
sentence shall not be construed as Landlord's consent for the Tenant to hold
over.

       14. TAXES ON TENANT'S PROPERTY. Tenant shall be liable for all taxes
separately


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levied or assessed against personal property, furnishings or fixtures placed by
Tenant in the Demised Premises. If any such taxes for which Tenant is liable are
levied or assessed against Landlord or Landlord's property and if Landlord
elects to pay the same or if the assessed value of Landlord's property is
increased solely by inclusion of personal property, furniture or fixtures placed
by Tenant in the Demised Premises, and Landlord elects to pay the taxes based on
such increase, Tenant shall pay to Landlord upon demand that part of such taxes
for which Tenant is primarily liable hereunder.

       15. RENT ADJUSTMENT - OPERATING EXPENSES. The Minimum rent
specified in Section 1 hereof, is subject to adjustment if and when the
Operating Expenses reflected in accordance with generally accepted accounting
principles exceed the Expense Stop, as herein defined. The term "Expense Stop"
shall mean the actual per square foot Basic Costs of operating the Building in
calendar year 1998 (the "Base Year"), and the term "Basic Costs" shall include
those expenses paid or incurred by the Landlord for maintaining, operating and
repairing the Land of which the Demised Premises are a part, the Building and
other improvements thereon and the personal property used in conjunction
therewith (the "Project") including but not limited to the cost of ad valorem
taxes, electricity, natural gas, ventilation, heating and air conditioning,
water, window cleaning, janitorial service, trash removal, insurance, including
but not limited to fire, extended coverage, liability, worker's compensation,
elevator or any other insurance carried in good faith by the Landlord and
applicable to the Project, painting, uniforms, customary property management
fees not to exceed five percent (5%) of the gross rents, supplies, sundries,
sales or use taxes on supplies or services, cost of wages and salaries of all
persons engaged in the operation, maintenance and repair of the Project, the
charges of any independent contractor who under contract with the Landlord or
its representatives does any of the work of operating, maintaining or repairing
the Project, legal expenses (however, limited to those which are for the benefit
of all tenants of the Building) and accounting expenses or any other expense or
charge, whether or not herein before mentioned. If any Project expense, though
paid in one year, relates to more than one calendar year, such expense shall be
proportionately allocated among such related calendar years in accordance with
general accepted accounting principles. The term "Operating Expenses" as used
herein, shall not include depreciation on the Building or equipment, interest,
leasing commissions, capital expenditures or executives' salaries.

       Adjustments, if any, shall be calculated according to generally accepted
standards of accounting for office building management and added proportionate
to the ratio of tenant's RSF to the total square footage of the Building. If
occupancy in the Building during the Base Year is less than ninety-five percent
(95%), the Operating Expenses for the Base Year shall be increased to an amount
that would have been incurred had the Building been ninety-five Percent (95%)
occupied during the Base Year, Landlord shall provide Tenant a reasonably
detailed written description of its computation and proration of the Operating
Expenses. In no event shall the amount of Operating Expenses be reduced below
the Expense Stop for the Base Year or previous year, nor shall Tenant's share
of Operating Expenses in any Lease Year of this Lease increase more than five
percent (5%) over and above the Tenant's share of the previous year's recovered
Operating Expenses.



                                       10

<PAGE>   11




       Within one hundred fifty (150) days after the close of the calendar year,
Landlord shall give Tenant a statement of the operating expenses for the
Building for such calendar year. If such operating expenses exceed the Expense
Stop, Tenant will pay Landlord, within thirty (30) days of statement receipt
Tenant's proportionate share of such increased expenses for the entire year
immediately preceding issuance of said statement and for the previous months in
the then current year. Thereafter, Tenant will pay in addition to the minimum
rents, an adjusted monthly rent, which reflects the most recent year's operating
expense increases, subject to increases as aforesaid. Tenant shall have the
right to audit the Operating Expenses at its sole cost and expense at Landlord's
place of business upon reasonable prior notice, during regular office hours. In
the event such audit reasonably determines a discrepancy in the amount paid by
Tenant, Tenant shall furnish Landlord a true copy thereof with a written request
that Landlord shall refund such amount within thirty (30) days after receipt
thereof. If Landlord disputes said audit and request for refund, Landlord shall
furnish Tenant written objections to the audit and request for refund within
said thirty (30) days period in lieu of a refund. The parties understand and
agree that Landlord can pass through Operating Expense increases over and above
the Base Year in any successive year; PROVIDED, however, in no event shall the
increase passed through exceed five percent (5%) of the Tenant's share of
Operating Expenses for the Lease Year immediately preceding the Lease Year in
which the increase in Operating Expense is to be added.

       If at the Commencement Date, or at termination of this Lease a partial
calendar year is involved, Operating Expenses shall be computed as though a full
calendar year was involved and prorated for such partial year. If this Lease
terminates other than at the end of a calendar year, an estimate of current
annual Operating Expenses shall be computed for the year of termination and any
increased rental based on such estimate shall be billed to the Tenant prior to
termination.

       16. EVENTS OF DEFAULT. The following events shall be deemed to be events
of default by Tenant under this Lease:

       A. Tenant shall fail to pay any installment of the rent hereby reserved
and such failure shall continue for a period of ten (10) days after receipt by
Tenant of written notice of said default.

       B. Tenant shall fail to comply with any term, provision, or covenant of
this Lease, other than the payment of rent, and such failure shall continue for
a period of thirty (30) days after receipt by Tenant of written notice of said
default, or in the case of a default not curable within thirty (30) days, if
Tenant shall fail to commence to cure the same within thirty (30) days, and
thereafter proceed diligently to complete the cure thereof.

       C. Tenant shall make an assignment for the benefit of creditors.

       D. Tenant shall file a petition under any section or chapter of the
United States Bankruptcy Code, as amended, or under any similar law or statute
of the United States or any State thereof, or Tenant shall be adjudged bankrupt
or insolvent in proceedings filed against



                                       11

<PAGE>   12




Tenant thereunder and such adjudication shall not be vacated or set aside or
stayed within the time permitted by law.

       E. A receiver or Trustee shall be appointed for all or substantially all
of the assets of Tenant and such receivership shall not be terminated or stayed
within sixty (60) days.

       F. Tenant shall desert or vacate all or any substantial portion of the
Demised Premises for a period of fifteen (15) days or more and Tenant fails to
pay rent as required under this Lease.

       17. REMEDIES. Upon the occurrence of any event of default specified in
Paragraph 16 hereof, in addition to any other remedy at law or in equity,
Landlord shall have the option to pursue any one or more of the following
remedies without any notice or demand whatsoever:

       A. Terminate this Lease in which event Tenant shall immediately surrender
the Demised Premises to Landlord and if Tenant fails to do so, Landlord may,
without prejudice to any other remedy which it may have for possession or
arrearage in rent, to the extent permitted by law, enter upon and take
possession and expel or remove Tenant and any other person who may be occupying
the Demised Premises or any part thereof, without being liable for prosecution
or any claim of damages therefor. 

       B. To the extent permitted by law, enter upon and take possession of the
Demised Premises and expel or remove Tenant and any other person who may be
occupying the Demised Premises or any part thereof without being liable for
prosecution or any claim for damages therefor, and if Landlord so elects, relet
the Demised Premises and receive the rent therefor, and Tenant agrees to pay to
Landlord on demand any deficiency that may arise by reason of such reletting.

       C. To the extent permitted by law, enter upon the Demised Premises
without being liable for prosecution or any claim for damages therefor, and do
whatever Tenant is obligated to do under the terms of this lease; and Tenant
agrees to reimburse Landlord on demand for any expenses which Landlord may incur
in thus effecting compliance with Tenant's obligations under this Lease, and
Tenant further agrees that Landlord shall not be liable for any damages
resulting to the Tenant from such action.

       Pursuit of any of the foregoing remedies shall not preclude pursuit of
any of the other remedies herein provided or any other remedies provided by law,
equity or both, nor shall pursuit of any remedy herein provided constitute a
forfeiture or waiver of any rent due to Landlord hereunder or of any damages
occurring to Landlord by reason of the violation of any of the terms, provisions
and covenants herein contained. Landlord's acceptance of rent following an event
of default hereunder shall not be construed as Landlord's waiver of such event
of default. No waiver by Landlord of any violation or breach of any of the
terms, provisions and covenants herein contained nor forbearance by Landlord to
enforce one or more of the remedies herein provided upon an event of default
shall not be deemed or construed to constitute a waiver of such default.



                                       12

<PAGE>   13




       18. SURRENDER. No act or thing done by the Landlord or its agents shall
be deemed an acceptance of a surrender of the Demised Premises, and no agreement
to accept a surrender of the Demised Premises shall be valid unless the same be
made in writing and subscribed by the Landlord.

       19. ATTORNEY'S FEES. In case it should be necessary or proper for
Landlord to bring any action under this Lease or to consult or place said Lease,
or any amount payable by Tenant thereunder, with an attorney concerning or for
the enforcement of any of Landlord's rights hereunder, then Tenant agrees in
each and any such case to pay to Landlord a reasonable attorney's fee, if
Landlord is the prevailing party. In case it should be necessary for Tenant to
bring any action under this Lease because of Landlord's default hereunder, then
Landlord agrees in each and every case to pay to Tenant a reasonable attorney's
fee if Tenant is the prevailing party.

       20. STANDBY LETTER OF CREDIT. Notwithstanding anything herein to the
contrary, and for purposes of further securing the full and timely performance
by the Tenant of all the terms and conditions hereof, within fifteen (15) days
after the date of this Lease, Tenant shall post an irrevocable standby letter of
credit with a declining balance and from Nations Bank, N.A., Tulsa, Oklahoma,
the issuing bank in form acceptable to Landlord, its successors and assigns, in
the sum of Three Hundred Fifty Thousand and No/100 Dollars ($350,000.00) for the
first three (3) years of the Lease Term, Two Hundred Fifty Thousand and No/100
Dollars ($250,000.00) for the fourth year of the Lease Term, and One Hundred
Fifty Thousand and No/100 Dollars ($150,000.00) for the remainder of the Lease
Term.

       21. QUIET ENJOYMENT. Landlord represents and covenants that it has full
right, power and authority to make this Lease and that Tenant, upon the payment
of the rentals and performing the covenants on Tenant's part to be performed
hereunder, shall and may peaceably and quietly have, hold and enjoy the Demised
Premises during the Term, free from interference or disturbance, but subject to
the terms and conditions of this Lease. Landlord agrees to make reasonable
efforts to protect Tenant from interference or disturbance by other tenants or
third persons; however, Landlord shall not be liable for any such interference
or disturbance, nor shall Tenant be released from any of the obligations of this
lease because of such interference or disturbance.

       22. NOTICES. Each provision of this Lease, or of any applicable
governmental laws, ordinances, regulations, and other requirements with
reference to the sending, mailing, or delivery of any notice, or with reference
to the making of any payment by Tenant to Landlord shall be deemed to be
complied with when and if the following steps are taken:

       A. All rent and other payments required to be made by Tenant to Landlord
       hereunder shall be payable to Landlord at the address hereinbelow set
       forth, or at such other address as Landlord may specify from time to time
       by written notice delivered in accordance herewith.



                                       13

<PAGE>   14




       B. Any notice or document required to be delivered hereunder shall be
       deemed to be delivered whether actually received or not, when deposited
       in the United States mail, postage prepaid, certified or registered mail,
       (return receipt requested), addressed to the parties hereto at the
       respective addresses set out opposite their names below, or at such other
       address as they have theretofore specified by written notice delivered in
       accordance herewith:

IF TO LANDLORD: American Southwest Properties, Inc.
                1700 West Albany
                Broken Arrow, OK 74012

IF TO TENANT:   MPSI Systems Inc.
                4343 South 118th East Avenue 
                Tulsa, OK 74145
                Attention President Ronald Harper

       23. SIGNAGE. Subject to City of Tulsa ordinances, and subject to
Landlord's prior written approval, which shall not be unreasonably withheld,
Tenant shall be permitted, at Tenant's sole cost, to install identifying signage
upon the Building and upon any Landlord provided monument signage in front of
the building. Landlord shall install at the outset of the Lease Term directory
signage inside the building at its sole cost on a one time basis; amendments and
modifications thereof shall be at Tenant's sole cost and expense. Tenant shall
have the right to install its signage on the south entry port and on the top of
the south end facade.

       24. HAZARDOUS MATERIALS AND AMERICANS WITH DISABILITIES. Landlord
represents that the Building and Demised Premises are presently, to the best of
Landlord's knowledge, information and belief after due inquiry, free of any
asbestos or any other hazardous material or substance. Landlord shall indemnify
and hold Tenant harmless from all direct (but not consequential loss and
damage) liability incurred in rectifying any alleged ADA violations that are
not caused by the Tenant during the Lease Term or Renewal Term.

       25. FORCE MAJEURE. Whenever a period of time is herein prescribed for
action to be taken by Landlord or Tenant (other than the payment of rent),
neither Landlord nor Tenant shall be liable or responsible for, and there shall
be excluded from the computation for any such period of time, any delays due to
strikes, riots, acts of God, shortages of labor or materials, war, governmental
laws, regulations, or restrictions, or any other causes of any kind whatsoever
which are beyond the control of Landlord or Tenant respectively.

       26. SEVERABILITY. If any clause or provision of this Lease is illegal,
invalid or unenforceable under present or future laws effective during the Lease
Term or Renewal Term, then and in that event, it is the intention of the parties
hereto that the remainder of this Lease not be affected thereby, and it is also
the intention of the parties to this Lease that in lieu of each clause or
provision of this Lease that is illegal, invalid or unenforceable, there be
added as a part





                                       14

<PAGE>   15




of this Lease a clause or provision as similar in terms to such illegal,
invalid, or unenforceable clause or provision as may be possible and be legal,
valid and enforceable.

       27. AMENDMENTS; BINDING EFFECT. This Lease may not be altered, changed, 
or amended except by instrument in writing signed by both parties hereto. The
terms, provisions, covenants and conditions contained in this Lease shall apply
to, inure to the benefit of, and be binding upon the parties hereto, and upon
their respective successors, assigns and legal representatives, except as
otherwise herein expressly provided.

       28. GENDER Words of any gender used in this Lease shall be held and
construed to include any other gender, and words in the singular number shall be
held to include the plural, unless the context otherwise requires. 

       29. CAPTIONS. The captions contained in this Lease are for convenience of
reference only, and in no way limit or enlarge the terms and conditions of this
Lease.

       30. RIGHT TO EXPAND. So long as Tenant is not in default hereof, Tenant
shall have the right to lease any vacant block of space in the Building as
described in Exhibit "E" hereof contiguous to the Demised Premises during the
Lease Term, that is not leased nor subject to lease and occupied by another.
Tenant shall provide Landlord written notice requesting the space, and the
acquisition thereof shall be subject to the terms hereof. The rent shall be at
"market" rate for the balance of the Lease Term and pro-rated tenant
improvements provided. If the parties cannot agree upon what the "market rate"
should be, then, in such event, within thirty (30) days thereof, the Landlord
and Tenant will each select an appraiser and their selected appraisers will
select a third appraiser. The appraisers will submit their evaluation within 30
days. The high and low appraisals will be eliminated and the middle appraisal
shall be the applicable "market rate." Each party will pay its own appraiser and
equally share the cost of the third appraiser. The vestibule north of the main
staircase on the second floor shall remain common area throughout the primary
term of the Lease, unless Tenant expands beyond the Demised Premises.

       31. RIGHT OF FIRST REFUSAL. So long as Tenant is not in default hereof
and provided Tenant has first exercised its right in respect to Expansion Area
as defined on Exhibit E during the Lease Term, Tenant shall have a right of
first refusal on all blocks of space in the Building. If Landlord receives an
arm's length offer on all or any part of such blocks, one or more, Landlord
shall provide Tenant ten (10) days written notice thereof in which Tenant shall
respond and accept or reject the space. The rent for the right of first refusal
space shall be at market rate for the remaining term and prorated Tenant
Improvements provided. If the parties cannot agree to market rate the parties
shall utilize the appraisal that is as described below. If the parties cannot
agree upon the market rate within thirty (30) days, the parties will each select
an appraiser and the appraisers will select a third appraiser. The appraisers
will submit their evaluations within thirty (30) days. The high and low
appraisals will be eliminated and the middle appraisal will be selected in
determining the market. Each party will pay its own appraiser and will equally
share the cost of the third appraiser. If Landlord does not lease the block of
space, the Right of First Refusal shall be reinstated.



                                       15
<PAGE>   16


       32. OPTION FOR EARLY TERMINATION. So long as Tenant is not in default
hereof effective as of the end of the 38th month of the Lease Term, Tenant shall
be entitled to the one time right to cancel this lease provided Tenant has given
Landlord written notice of the exercise of this option on or before the end of
the 35th month of the Lease Term and Tenant has made a simultaneous cash payment
of an early termination cancellation charge. An early termination-cancellation
charge calculated in accordance with Exhibit "F" attached hereto and
incorporated herein by reference shall be assessed for the recovery of the
unamortized Tenant improvements and unrealized rental. This early termination
charge shall in no way relieve Tenant of the responsibility to Landlord to leave
the Demised Premises in good condition and order, less normal wear and tear, and
clean and free from trash and debris.

       33. OPTION TO REDUCE SIZE OF DEMISED PREMISES. So long as Tenant is not 
in default hereof, effective as of the end of the 38th month of the Lease Term,
Tenant shall be entitled to the one time right provided Tenant has given
Landlord written notice of said exercise on or before the end of the 35th month
of the Lease Term, to reduce the size of the Demised Premises by tendering back
to the Landlord not more than 11,244 RSF (i.e., first floor of F, M. G & L East
as shown on Exhibit "E") and quitting that part of Demised Premises in good,
clean condition, ordinary wear and tear excepted. Should Tenant elect to
exercise this option, an additional sum calculated as set forth on Exhibit "F"
attached hereto and incorporated herein by reference will be added to the
rental rate for years four (4) and five (5) for the remaining RSF.       

       34. OPTION TO RENEW LEASE. So long as Tenant is not in default thereof
upon six (6) months prior written notice to Landlord, Tenant shall have a right
to renew this lease for one (1) additional year, commencing the day after the
Expiration Date and expiring at Midnight of the day preceding the first
anniversary thereof (the "Renewal Term").

       35. ADDITIONAL PROVISIONS.

       A. Time is of the essence in the performance of each provision of this
Lease.

       B. Except as set forth in 35E below, Tenant represents and warrants to
Landlord that Tenant has not incurred and will not incur any liability for
brokerage fees, finders fees, agents commissions or similar compensation to
third parties in connection with this transaction. In the event Tenant has
incurred any such fees, commissions or compensation, said fees, commissions and
compensation so incurred shall be charged solely against Tenant and Tenant
agrees to indemnify Landlord against and hold landlord harmless from any and all
liabilities arising from any claim for such fees, commissions or compensation,
including without limitation, the cost of counsel fees in connection therewith.

       C. It is understood and agreed that this Lease, including all rights of
Tenant hereunder is subject and subordinate to any mortgage or deed of trust or
trustee indenture ("mortgage) which may or hereafter affect this Lease or the
Property which the Demised Premises form a part and to any and all advances made
under any such mortgage and to the interest thereon, and all renewals,
replacements and extensions thereof. This section shall be self-operative and no
further instrument or subordination shall be required, but Tenant shall
nevertheless at any time





                                       16


<PAGE>   17


hereafter, on the demand of Landlord, execute any instruments, releases or other
documents that may be reasonably required by any such mortgage holder or any of
their respective successors-in-interest to evidence such subordination. In the
event of termination of this Lease through foreclosure of any mortgage to which
this Lease is subordinated, Tenant shall, upon the demand of the purchaser of
the Property at the foreclosure sale thereof, attorn to and accept such
purchaser as Landlord under this Lease or upon demand, enter into a new lease
agreement with such purchaser for the unexpired term of this Lease at the same
rent and under the same provisions of this Lease. Tenant shall be obligated to
subordinate its interest under the Lease to any lien or encumbrance which may
hereafter be placed on, against or affecting the Premises only if, and on the
condition that, Landlord shall provide Tenant with a non-disturbance agreement
in favor of Tenant from the holder of such lien or encumbrance in a form
reasonably acceptable to Tenant. Landlord shall, contemporaneously herewith,
provide Tenant with a non-disturbance agreement in favor of Tenant from the
holder of any existing lien or encumbrance, if any, now on, against or affecting
the Premises in a form reasonably acceptable to Tenant.

       D. Tenant agrees, at any time and from time to time, upon not less than 
ten (10) business days prior written notice by Landlord, to execute, acknowledge
and deliver to Landlord a statement in writing (a) certifying that this Lease is
unmodified and in full force and effect, or if there have been any
modifications, that this Lease is in full force and effect as modified, (b)
stating the dates to which the rent and any other charges hereunder have been
paid by Tenant, (c) stating whether or not to the best knowledge of Tenant,
Landlord is in default in the performance of any covenant, agreement or
condition contained in this Lease, and, if so, specifying each such default of
which Tenant may acknowledge and (d) stating the address to which notices to
Tenant should be sent. Any such statement delivered pursuant hereto may be
relied on by any owner of the Property, any prospective purchaser of the
Property, and any present or perspective mortgagee, deed of trust holder or
trustee for bondholders with respect to the Property or Landlord's interest.

       E. Trammell Crow MW, Inc. represents Tenant in this transaction. Landlord
shall not be required to pay Broker's professional services fees, and Tenant
shall save, defend, indemnify and hold Landlord harmless of and from any and all
loss therefrom.

       F. MEASUREMENT STANDARD. All space in the building other than that
initially leased by Tenant hereunder shall be measured based on the measurement
standards contained in the American National Standard Method of Measuring Floor
Area and Office Projects published by the Building Owners and Managers
Association International.

       G. CONSENTS. Wherever in this Lease Landlord or Tenant's consent is
required, said consent shall not be unreasonably withheld, delayed or
conditioned.

       H. SATELLITE DISH. During the Lease Term, for as long as Tenant is not in
default of this Lease, and subject to Landlord's right to decide the location
thereof, Tenant shall have the right to install, at its sole cost and expense,
antennas on the roof of such building (including necessary connections to the
Demised Premises) for use by the Tenant. Any such antennas shall be installed in
accordance with all applicable laws and building codes. Tenant shall have the




                                       17
<PAGE>   18




option to remove such antennas at the expiration or earlier termination of the
Lease, provided, in the event of removal Tenant shall repair any damage to the
roof caused by such removal. Tenant shall further be required to repair any
damage to the roof caused by the installation of the antenna and to provide or
collect insurance relating to said antenna.

         I. SPRINKLERING. If at any time before or during the Lease Term
sprinklering is required by final decree of any governmental authority of
competent jurisdiction in all or any part of the Demised Promises, or the
Building, Landlord, at Landlord's sole cost or expense shall install said
sprinklering. In conducting said installation, Landlord shall use its best
efforts not to interfere with Tenant's use of the Premises.

         J. FIBER OPTICS CABLING. Within one hundred fifty (150) days of the
full execution of this Lease, Landlord, at Landlord's sole cost and expense
shall cause fiber optic cabling to be brought to the Building with reasonably
sufficient capacity to service the reasonably anticipated needs of the Building
and its Tenants.

         K. ARBITRATION. All disputes and controversies between the parties
hereto as may arise out of or incident to this Lease Agreement shall be settled
by binding, informal mediation or formal arbitration in accordance with the
Commercial Rules of the American Arbitration Association and pursuant to the
Federal Arbitration Act.

         WITNESS, the signature of the parties hereto in multiple copies, this
11 day of February, 1998.


                                      "LANDLORD"

                                      AMERICAN SOUTHWEST
                                          PROPERTIES, INC.

                                      By: /s/ JACK WRIGHT
                                         ---------------------------------------
                                                                   its President


                                      "TENANT"

                                      MPSI SYSTEMS INC.

                                      By: /s/ JAMES C. AUTEN
                                         ---------------------------------------
                                                             its Vice President,
                                                             Finance & CFO




                                       18
<PAGE>   19




STATE OF OKLAHOMA                  )
                                   )
COUNTY OF TULSA                    )

         Subscribed and acknowledged before me by Jack Wright, President of
American Southwest Properties, Inc., a corporation, this 13th day of February,
1998.

                                         /s/ PATTY R. NORTHAM
                                         ---------------------------------------
                                                     NOTARY PUBLIC

My Commission expires:
4-15-2000
----------------------
[NOTARIAL SEAL]


STATE OF OKLAHOMA                  )
                                   )
COUNTY OF TULSA                    )

         Subscribed and acknowledged before me by JAMES C. AUTEN, President of
MPSI Systems Inc., a corporation, this 13th day of February, 1998.


                                         /s/ LINDA KAY WELLS
                                         ---------------------------------------
                                                     NOTARY PUBLIC



My Commission expires: 
July 21, 1999
----------------------
[NOTARIAL SEAL]




                                       19
<PAGE>   20




EXHIBIT A TO LEASE AGREEMENT BETWEEN AMERICAN SOUTHWEST PROPERTIES, INC. AND
MPSI SYSTEMS, INC. IN RESPECT TO THE SOUTHPARK BUILDING, TULSA, OKLAHOMA

                         FLOOR PLAN OF DEMISED PREMISES
      (NOT LESS THAN 54,436 RSF [PLUS 823 RSF(1) NO CHARGE STORAGE SPACE])



















---------------
(1) RSF (rentable square footage) is the actual square footage within the
Demised Premises measured from the midline of all demising walls and windows.



                                       20
<PAGE>   21
                     Exhibit A - Page 1 of 2 - Floor Plan


                 [1st FLOOR - SOUTHPARK BUILDING FLOOR PLAN]
<PAGE>   22
                     Exhibit A - Page 2 of 2 - Floor Plan


                 [2ND FLOOR - SOUTHPARK BUILDING FLOOR PLAN]

<PAGE>   23
            EXHIBIT B TO LEASE AGREEMENT BETWEEN AMERICAN SOUTHWEST
      PROPERTIES, INC. AND MPSI SYSTEMS, INC. IN RESPECT TO THE SOUTHPARK
                           BUILDING, TULSA, OKLAHOMA

                  WORK LETTER RELATIVE TO TENANT IMPROVEMENTS

1. As to all leasehold improvements to be constructed and installed on the
Demised Premises:

         A. Such shall conform to and be in compliance with all applicable laws,
statutes, ordinances, rules and regulations of governmental authority,
regardless of jurisdiction;

         B. Tenant's agents, employees, architects, space planners, engineers
and/or contractors who are to plan and do the work, together with the plans
proposed to be utilized, must be reasonably preapproved by Landlord in writing,
PROVIDED that Tenant is no way relieved of its responsibility to maintain the
building and structural integrity related to Tenant's construction;

         C. Tenant shall maintain appropriate liability and property insurance
naming Landlord as an additional insured, against risk or loss, including
without limitation, for bodily injury, property damage, employer's liability,
and worker's compensation, fire and extended perils acceptable to Landlord
during the construction of aid leasehold improvements;

         D. All plans and specification for the work shall be preapproved in
writing by Landlord and true and correct copies thereof, inclusive of all
material change orders, if any, shall be attached to and made a part of this
Exhibit "B." Landlord shall respond to Tenant's request for approval of Tenant's
plans and specifications within three (3) days after receipt thereof; the
failure of Landlord to respond within such period shall constitute approval of
such plans and specifications. In the event Landlord shall not approve the plans
and specifications, Landlord shall notify Tenant of its objections thereto.
Landlord and Tenant shall thereafter work cooperatively and in good faith to
reach agreement upon mutually agreeable plans and specifications. If,
notwithstanding their respective reasonable good faith efforts, Landlord and
Tenant are unable to agree upon mutually acceptable plans and specifications
within fifteen (15) days after Tenant has first submitted its plans and
specifications to Landlord, then Tenant shall have the right to terminate the
Lease. Tenant shall not be responsible for Landlord's own costs related to
review, construction management or supervision fees, costs or expenses related
to the work Landlord agrees to reasonably assist Tenant in obtaining all
necessary permits for the Tenant work from appropriate governmental authorities.

         E. All contractors and subcontractors of Tenant, as applicable, shall
furnish certificates of insurance evidencing worker's compensation insurance
coverage for their respective employees before undertaking any work on the
Demised Premises;

         F. All work shall be done in a good and workmanlike manner and
materials used shall be of good quality and Tenant shall be responsible to
assure structural integrity (excluding

                     

                                       21



<PAGE>   24




preexisting conditions and latent defects) of the Building and Demised Premises
are not impaired, and

         G. Landlord shall pay to Tenant the actual costs of tenant
improvements, but not to exceed $544,360 ($10.00 per RSF X 54,436 RSF), and not
to exceed $5,987.96 ($.11 per RSF X 54,436 RSF) for all tenant improvement
planning), which shall be payable by Landlord to Tenant on presentation of
invoices and lien waivers as construction progresses and as the parties may
otherwise agree; the final draft shall not be payable until said tenant
improvements are completed, in whole or in substantial part. Any allowances
unspent by Tenant shall be reduced from rent on a nine percent (9.0%)
amortization basis over the Lease Term. 

2. The relationship between the parties is solely that of Landlord-Tenant and no
agency, partnership or joint venture agreement is intended nor shall be deemed
to arise from this work order, or otherwise implied from the conduct of the
parties hereto.

3. Landlord shall, at Landlord's sole, cost and expense, for the original tenant
improvements applicable to the Demised Premises as well as any expansions
thereof, within the same time said leasehold improvements are being constructed
and installed by Tenant, do the following:

         A. install building standard miniblinds on all exterior windows; an
additional elevator providing second floor access from the front of the
building; a stairwell "branch" accessing the south tenant entry, and in areas
where there is no ceiling install budding standard lights, ceiling grid, ceiling
tiles and duct drops from the plenum, provided said ceiling installation shall
commence immediately upon lease execution and shall proceed diligently to
completion.

         B. Install a unisex, handicapped restroom on each floor within ninety
(90) days after the Lease is executed by the Landlord and Tenant, and represent
upon its best knowledge, information and belief after due inquiry that the
elevator and bathrooms meet minimum ADA requirement for dimension and are wheel
chair accessible. Should regulatory authorities require changes to the Building
for compliance with ADA now or in the future, Landlord sole obligation shall
be, at its sole cost and expense, to cure such defects and to bring the Building
into compliance and all such expenses shall be added to the operating expenses
of the Building for purposes of later determining pass-throughs to Tenant
subject to the cap on increases in Operating Expenses set forth in Section 15 of
this Lease. Landlord will coordinate construction with Tenant's construction to
insure that it does not delay Tenant's work.



                                       22



<PAGE>   25





             EXHIBIT C TO LEASE AGREEMENT BETWEEN AMERICAN SOUTHWEST
       PROPERTIES, INC. AND MPSI SYSTEMS, INC. IN RESPECT TO THE SOUTHPARK
                            BUILDING, TULSA, OKLAHOMA


                               JANITOR'S SCHEDULE


                                 SEE ATTACHMENT










                                       23



<PAGE>   26
                                  [AMERICAN BUILDING MAINTENANCE CO. LETTERHEAD]




                            JANITORIAL SPECIFICATIONS

                                    SOUTHPARK


ENTRANCE LOBBIES/BUILDING CORRIDORS

1.   Daily Services: Five Days Per Week

     Sweep and spot clean all flooring.
     Vacuum carpets completely. Spot clean spillages.
     Dust ledges within reach.
     Damp mop spillage as needed.
     Empty and wash cigarette receptacles.
     Spot clean walls and doors.
     Clean entrance door glass. 
     Clean entrance mats as necessary.
     Clean and polish all metal at entrances and other areas of building 
        lobby.
     Clean and polish drinking fountains.

2.   Weekly Services:

     Spot clean carpet in heavy traffic areas.

3.   As Needed:

     Detail vacuum carpeted areas. 
     Clean all baseboards.

STAIRWAY

Remove debris and vacuum clean weekly. 
Sweep carpeted stair landings and steps. 
Damp clean handrails weekly.

RESTROOMS

1.   Daily Services: Five Days Per Week

     Clean and sanitize restrooms, wash basins, all dispensers and chrome
        fittings.                    
     Clean mirrors and frames.
     Wet mop floors with disinfecting cleaner.
     Sanitize toilets, both sides of toilet seats, urinals and sanitary napkin
        recepticles.                              
     Dust ledges and partitions.
     Report to building office any fixture not working properly.
     Damp clean as required:  walls, partitions, ledges, sills and counters.



<PAGE>   27




JANITORIAL SPECIFICATIONS -- Continued

     Refill all dispensers (towels, tissue, hand soap, napkins from building
        stock).
     Gather all waste and place for disposal.
     Spot clean partitions, walls and doors. 
     Turn off all lights.

2.   Monthly Services:

     Dust vacuum ceiling vents. 
     Wash metal partition and ceramic tile walls using disinfectant.
     Perform high dusting, including walls.

OFFICE AREAS

1.   Daily Services: Five Days Per Week

     Gather all waste and place for disposal.
     Empty and polish all ashtrays.
     Dust mop tile with chemically treated dust mops.
     Spot clean spillage from tile floors.
     Vacuum carpets in usage areas (spot clean as required).
     Dust desks, chairs, and all other horizontal surfaces within reach.
     Spot clean glass desk tops.
     Properly position furniture, and waste baskets.
     Spot clean desk tops and counter tops.
     Spot clean partition door glass.
     Clean and polish drinking fountains.
     Dust all ledges and flat surfaces within reach to maintain them dust
        free. Upon completion of cleaning, all lights will be turned off.    
     Check and lock all doorways, as instructed by management.

2.   Weekly Services:

     Remove finger smudges from woodwork, walls and partitions. 
     Perform low dusting not done daily. 
     Vacuum carpeted areas complete, including edges. 
     Dust all baseboards. 
     Dust all vertical surfaces on furniture and spot clean. 
     Dust all door louvers and other ventilation louvers within reach.

3.   Monthly Services:

     Perform high dusting (i.e. door sash, tips of partitions).
     Dust all picture frames, charts and similar hangings not dusted in daily
        or weekly cleaning. 
     Dust or vacuum all air vents.






<PAGE>   28


JANITORIAL SPECIFICATIONS - Continued


4.   Quarterly Services:

     Dust all venetian blinds.
     Vacuum upholstered furniture (or as needed).

       WINDOW CLEANING SERVICE

WINDOW CLEANING SERVICE

We will wash all windows annually. Cost of cleaning will be in included in your
monthly billing.

CARPET CLEANING SERVICE

We will shampoo your carpets annually. Cost of cleaning is included in your
monthly billing.

SUPPLIES AND EQUIPMENT

We will furnish all janitorial supplies and equipment required to properly
perform the above work.

       
FIDELITY BOND
All of our employees are covered by a Fidelity Bond.


<PAGE>   29



                       

                 EXHIBIT D TO LEASE AGREEMENT BETWEEN AMERICAN
                SOUTHWEST PROPERTIES, INC. AND MPSI SYSTEMS INC.
                      IN RESPECT TO THE SOUTHPARK BUILDING,
                                 TULSA, OKLAHOMA










                         BUILDING RULES AND REGULATIONS












                                       24
<PAGE>   30
                                  EXHIBIT "D"

                          RULES AND AGREED REGULATIONS

     1.   Tenant agrees, upon termination of this Lease, to return all keys to 
the Demised Premises to Landlord. Tenant shall not alter any lock or install a 
new or additional lock or bolt on any door of the Demised Premises without the 
prior written consent of Landlord.

     2.   Tenant will refer all contractors, contractor's representatives and 
installation technicians, rendering any service to Tenant, to Landlord for 
Landlord's approval, and control before performance of any contractual service. 
This provision shall apply in all work performed in the Building including 
installations of telephones, telegraph equipment or any other physical portion 
of the Building.

     3.   Movement in or out of the Building of furniture or office equipment, 
or dispatch or receipt by Tenant of any merchandise or materials which requires 
use of elevators or stairways, or movement through Building entrances or lobby 
shall be restricted to hours designated by Landlord. Tenant is to assume all 
risk as to damage to articles moved and injury to persons or the public engaged 
or not engaged in such movement, including equipment, property and personnel of 
Landlord if damaged or injured as a result of acts in connection with carrying 
out this service for Tenant from time of entering the tract on which the 
Building stands to completion of work; and Landlord shall not be liable for 
acts of any person engaged in, or any damage or loss to any of said property or 
persons resulting from any act in connection with such service performed for 
Tenant.

     4.   Unless written approval has been given by Landlord, no signs will be 
allowed in any form on the exterior of Building or windows inside or out, and 
no signs, except in uniform location and uniform styles approved by Landlord, 
will be permitted in the public corridors or on corridor doors or entrances to 
Tenant's space. Tenant will pay for any approved signage.

     5.   No draperies, shutters, or other window covering shall be installed 
on exterior windows or walls or windows and doors facing public corridors 
without Landlord's prior written approval.

     6.   No portion of the Demised Premises or any other part of Building 
shall at any time be used or occupied as sleeping or lodging quarters.

     7.   Tenant shall not place, install or operate on the Demised Premises or 
in any part of the Building any engine, stove, or machinery, or conduct 
mechanical operations or cook thereon or therein, or place or use in or about 
premises any explosives, gasoline, kerosene, oil, acids, caustics, or any other 
inflammable, explosive, or hazardous materials without written consent of 
Landlord.

     8.   Landlord will not be responsible for lost or stolen personal 
property, equipment, money, or jewelry from the Demised Premises or public 
rooms regardless of whether such loss occurs when area is locked against entry 
or not.

     9.   No birds or animals shall be brought into or kept in or about the 
Building.

     10.  Landlord will not permit entrance to the Demised Premises by use of 
pass keys controlled by Landlord, to any person at any time without written 
permission by Tenant, except employees, contractors, or service personnel 
directly supervised by Landlord and employees of the United States Postal 
Service.

     11.  None of the entries, passages, doors, elevators, elevator doors, 
hallways, or stairways shall be blocked or obstructed, or any rubbish, litter, 
trash, or material of any nature placed, emptied or thrown into these areas, or 
such areas be used at any time except for ingress by Tenant, Tenant's agents, 
employees, or invitees.

     12.  Tenant and its employees, agents and invitees, shall observe and 
comply with the driving and parking signs and markers on the premises 
surrounding the Building.

     13.  Landlord shall have the right to prescribe the weight and position of 
safes, computers and other heavy equipment which shall, in all cases, in order 
to distribute their weight, stand on supporting devises approved by Landlord. 
All damage done to the Building by placing in or taking out any property of 
Tenant while in the Building shall be repaired promptly at the expense of 
Tenant.

     14.  To insure orderly operation of the Building no ice, mineral water or 
other beverages, food, towels, newspapers, etc., shall be delivered to the 
Demised Premises except by persons and at times approved by Landlord in writing.

     15.  Should Tenant require telegraphic, telephonic, annunciator or other 
communication services, Landlord shall direct where and how wires are to be 
introduced and placed and none shall be introduced or placed except as Landlord 
shall direct.

     16.  Without Landlord's prior approval, Tenant shall not install any radio 
or television antenna, loudspeaker, music system or other devise on the roof or 
exterior walls of the Building or on common walls with adjacent tenants.
<PAGE>   31
     17.  No hand trucks or other vehicles of any kind shall be used in or 
brought into the Building or the Demised Premises by Tenant or others unless 
such vehicle shall have been inspected and approved in writing by Landlord.

     18.  Tenant shall store all its trash and garbage within its Demised 
Premises. No material shall be placed in the trash boxes or receptacles if such 
material is of such nature that it may not be disposed of in ordinary and 
customary manner of removing and disposing of trash and garbage and without 
being in violation of any law or ordinance governing such disposal. All garbage 
and refuse disposal shall be made only through entryways and elevators provided 
for such purposes and at such times as Landlord shall designate.

     19.  These Rules and Regulations are in addition to, and shall not be 
construed to in any way modify, alter or amend, in whole or in part, the terms, 
covenants, agreements and conditions of any lease covering premises in the 
Building.

     20.  Landlord reserves the right to make such other reasonable rules and 
regulations as in its judgment may from time to time be needed for the safety, 
care and cleanliness of the Building, and for the preservation of good order 
therein.


<PAGE>   32
                 EXHIBIT E TO LEASE AGREEMENT BETWEEN AMERICAN
               SOUTHWEST PROPERTIES, INC. AND MPSI SYSTEMS INC
                    IN RESPECT TO THE SOUTHPARK BUILDING,
                               TULSA, OKLAHOMA
                                      


                        EXPANSION BLOCKS DEFINED WITH
                          CONTRACTION OPTION DEFINED



                                      25
<PAGE>   33
              Exhibit E, Page 1 of 2 - Expansion Blocks Defined
                                       Contraction Option Defined


                            [1ST FLOOR FLOOR PLAN]
<PAGE>   34
              Exhibit E, Page 2 of 2 - Expansion Blocks Defined
                                       


                            [2ND FLOOR FLOOR PLAN]
<PAGE>   35
                EXHIBIT F TO LEASE AGREEMENT BETWEEN AMERICAN
               SOUTHWEST PROPERTIES, INC. AND MPSI SYSTEMS INC



                             CALCULATION OF EARLY
                       TERMINATION-CANCELLATION CHARGE



                                      26
<PAGE>   36
                                    EXHIBIT F

  CALCULATION OF CONTRACTION CHARGE AND EARLY TERMINATION-CANCELLATION CHARGE
(Assume that Tenant Improvements are $10.00 per square foot and total leased 
space is 54,436 square feet)

     $10.00 Improvemets Per Square Foot
      $1.50 Moving Allowance Per Square Foot
      $0.11 Space Planning Per Square Foot
-----------
     $11.61 Total Tenant Investment Per Square Foot

     $11.61 Total Tenant Investment Per Square Foot
     x54436 Square Feet Rented
-----------
$632,001.96 Total Tenant Investment
Amortized over 5 years at 9% = $13,119.32 per month

 $13,119,32
        x12 Months
    /54,436 Square Feet Rented
-----------
      $2.89 Tenant Investment Charge per square foot

Rental rate was marked down by .50 in year 1 and .25 in year 2.
This is compensated for in years 4 and 5.
If years 4 and 5 are cancelled, then this will not be compensated for.
Therefore, we have added this into the cost of contraction or cancellation.

Unamortized improvements + unreimburesed rental adjustments=
2.89 + .25 = 3.14 per square foot in year 4
2.89 + .50 = 3.39 per square foot in year 5

CONTRACTION CHARGE
$3.14 x 11,244 square feet = $35,306.16
$3.39 x 11,244 square feet = $38,117.16
Total                        $73,423.32

Total Square Footage of 54,436 Less Contraction Space = 43,192 square feet 
remaining $73,423.32/43,192 square feet equals $1.70 per square foot to be 
added to rental rate of remaining square footage.

EARLY TERMINATION-CANCELLATION CHARGE
$3.14 x 54,438 square feet = $170,929.04 per year divided by 12 months = 
$14,244.09
$3.39 x 54,436 square feet = $184,538.04 per year divided by 13 months = 
$15,378.17

The present value of 12 monthly payments of $14,244.09 followed by 12 monthly 
payments of $15,378.17 at 9% is equal to $326,074.26. $326,074.26 divided by 
54,436 square feet is equal to $5.99 per square foot. A penalty of $2.28 per 
square foot has been added to this number to equal a cancellation charge of 
$8.27 per square foot.