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                                                                   EXHIBIT 10.15

                                 LEASE AGREEMENT

            THIS AGREEMENT OF LEASE, made this 7th day of December, 1995 by and
between Richard L. Dietrick and Garnetta J. Dietrick (hereinafter called
"Landlord") and Leet-Melbrook, Inc. (hereinafter called "Tenant") .

                              W I T N E S S E T H:

            1. DEMISED PREMISES. Landlord, for and in consideration of the
covenants and agreements herein set forth, and the rent hereafter specifically
reserved, does hereby lease to Tenant, the entire building located at 18810
Woodfield Road, Gaithersburg, Maryland (hereinafter called the "Building" or
"Demised Premises").

            2. TERM.

                  (a) Subject to and upon the terms and conditions, set forth
herein, this lease shall continue in force for a term of five (5) years
beginning on the 15th day of January, 1996 ("Commencement Date"), and ending on
the 14th day of January 2001 ("Termination Date").

                  (b) Provided the Tenant is not then in Default, Tenant shall
have the right, exercisable not less than six (6) months prior to the
Termination Date, to extend this Lease for an addition period of five (5) years,
upon the same terms and conditions as set forth herein for the initial term
(other than his option to extend).

            3. RENT AND OTHER CHARGES.

                  (a) Tenant covenants and agrees to pay to Landlord for the
Demised Premises, without previous notice or demand, and without deduction,
set-off or abatement, basic annual rent in the amount of One Hundred Forty-One
Thousand Two Hundred Dollars ($141,200) payable in equal monthly installments,
in advance, of Eleven Thousand Seven Hundred Sixty-Six Dollars and 67/100
($11,766.67) (hereinafter referred to as the "basic monthly rent"), on the first
day of each and every calendar month during the term hereof Rent for any partial
month shall be prorated at the rate of one-thirtieth (1/30th) of the basic
monthly rent per day. Notwithstanding the foregoing, the first two months rent
otherwise payable hereunder shall be abated and Tenant's first monthly payment
shall be due March 15, 1996.

                  (b) Commencing with the second lease year and for each
subsequent lease year during the original and any extended term, basic annual
rent shall be increased annually by an amount equal to two percent (2%) of the
basic annual rent payable during the preceding lease year.

                  (c) Tenant shall pay as additional rent and without notice,
abatement, deduction or set-off, all sums, costs and expenses which Tenant, in
any of the provisions of this Lease, or through a separate agreement relating to
the Demised Premises, assumes or agrees to pay, including but not limited to
tenant work, and in the event of any non-payment thereof, the Landlord shall
have (in addition to all other rights and remedies) all the rights and remedies
provided herein or by law in the case of non-payment of the basic monthly rent.

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                  (d) All payments due to Landlord, including the basic monthly
rent, additional rent, and all other reimbursements and charges due under the
terms of this Lease, shall be made at 14727 Crossway Road, Rockville, Maryland
20853, or such other address of which Tenant is given written notice by
Landlord. Rent checks are to be made payable to Richard and Garnetta Dietrick,
or such other person, firm or corporation as the Landlord may hereafter
designate in writing.

                  (e) Tenant covenants and agrees to pay, as additional rent,
interest at the rate of one and one-half percent (1 1/2%) per month if any
payments are not received within ten (10) days of their due date.
Notwithstanding the foregoing, Landlord shall waive application of the late
payment penalty with respect to the first late payment in any calendar year,
provided that payment is received by Landlord within two (2) days after notice
from Landlord to Tenant that the payment was not received by the due date.

            4. INSURANCE AND TAXES.

                  Landlord shall pay all real estate taxes and the cost of
insurance carried by Landlord with respect to the Building.

            5. TENDER OF POSSESSION. Landlord shall tender possession of the
Demised Premises to Tenant on the Commencement Date, "As Is." "As Is" shall mean
in good order and condition, broom clean and in compliance with existing
building codes. Tenant may inspect building prior to occupancy. Any damage or
faults noted upon inspection will be Landlord's responsibility to repair.
Landlord shall not be obligated to, and shall not, perform any alterations or
improvements to the Demised Premises. Landlord shall not be liable or
responsible for any claims, damages or liabilities by reason of any delay in
tender of possession, nor shall the obligations of the Tenant provided herein be
excused by reason of any such delay, except that Tenant shall not be obligated
to pay rent until Landlord has tendered possession of the Demised Premises. If
Landlord shall not have tendered possession of the Demised Premises, within
thirty (30) days from said commencement date, Tenant may, at Tenant's option,
and as Tenant's sole remedy, by notice in writing to the Landlord, cancel this
Lease with immediate return of security deposit. Upon occupancy of the Demised
Premises Tenant shall immediately execute an agreement specifying the
commencement and termination date of this Lease.

            6. DEPOSITS. Tenant, concurrently with the execution of this Lease,
has deposited with the Landlord a Security Deposit in the amount of Eleven
Thousand Seven Hundred Sixty-Six Thousand and 67/100 ($11,766.67), to be held by
Landlord, and shall be applied by Landlord toward the cost of repairing or
replacing any equipment damaged or removed by Tenant or its guests, agents or
employees from the Demised Premises by Tenant or its-guest, agents or employees
and toward repair of damage (other than ordinary wear and tear) to the Demised
Premises caused or permitted by Tenant or its guests, agents or employees or for
any other liabilities or indebtedness of Tenant to Landlord with notice to
Tenant. This deposit is not to be used or applied by Tenant as a substitute for
rent due any month but may be so applied by Landlord at any time at Landlord's
option. The use, application or retention of the Security Deposit, or any
portion thereof shall not prevent Landlord, from exercising any other right or
remedy provided by this Lease or by law and shall not operate as a limitation on
any recovery to which Landlord may otherwise be entitled. If any portion of the
Security Deposit is used,

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applied or retained by Landlord in accordance with this Lease, Tenant agrees,
within ten (10) days after written demand therefor is made by Landlord, to
deposit cash with the Landlord in an amount sufficient to restore the Security
Deposit to its original amount. Landlord will promptly place the security
deposit in a checking account at a Federally insured financial institution and
the interest shall accrue to Tenant's benefit and be returned to Tenant within
thirty (30) days if and when it is entitled to the refund of the security
deposit.

            7. MAINTENANCE. Tenant agrees that it, at its sole expense, will
keep the Demised Premises, plumbing systems, electrical and HVAC system and
structural components of the Demised premises, in good order and condition and
will, at the expiration or other termination of this Lease, surrender and
deliver up the same broom clean and in like good order and condition as the same
now is or shall be at the commencement of the term hereof, ordinary wear and
tear and damage by the elements, fire and other unavoidable casualty not due to
the negligence of Tenant excepted.

                  Tenant shall also maintain the parking areas and shall arrange
for seasonal maintenance for the HVAC system. Tenant shall be responsible for
keeping grounds and walkways free of debris. Tenant shall be responsible for
snow and ice removal on walkways.

                  Landlord will, at its sole expense, keep in good repair the
roof and exterior walls.

                  During the first year of the initial term only and except for
routine maintenance which shall always be the responsibility of the Tenant,
Landlord will make all necessary repairs and replacement for the heating,
ventilating and air-conditioning systems and equipment installed by Landlord and
serving the Demised Premises unless damaged by act or neglect of Tenant.

                  Landlord will arrange and pay for maintenance of landscaping
and lawn areas. Landlord will arrange and pay for removal of snow and ice from
parking areas servicing the building, within-a reasonable time after
accumulation thereof.

            8. USE OF DEMISED PREMISES. Tenant shall use the Demised Premises in
accordance with, all applicable zoning and other governmental regulations. Tempt
will not obstruct, interfere or conflict with the fire laws) or regulations, or
with any insurance policy upon the Building or any part thereof, or with any
statutes, rules or regulations now existing or subsequently enacted or
established by the local, state or federal governments. Nor will the Tenant use
or permit the Demised Premises, or any part thereof, to be used for any
residential, disorderly, unlawful or hazardous purpose, nor for any purpose
other than hereinbefore specified, without the prior written consent of
Landlord.

            9. LEASEHOLD IMPROVEMENTS AND ALTERATIONS. Tenant agrees to install
a drop ceiling and make other improvements to the Demised Premises, as more
fully set forth in Exhibit A attached hereto and made a part hereof. The cost of
any leasehold improvements will be borne by Tenant.

                  Tenant agrees not to make any additions or alterations,
structural or otherwise, in or upon the Demised Premises, without first having
obtained the Landlord's written

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consent, which consent shall not unreasonably be withheld, delayed or
conditioned. All additions, alterations, installations, changes, replacements or
improvements, other than Tenant's trade fixtures upon the Demised Premises shall
remain upon the Demised Premises, and be surrendered with the Demised Premises
at the expiration or other termination of this Lease without disturbance,
molestation or injury. Should the Landlord elect that certain alterations,
installations, changes, replacements, additions to or improvements upon the
Demised Premises be removed upon expiration or other termination of this Lease,
or any renewal period hereof, Tenant hereby agrees to cause the same to be
removed at Tenant' s sole cost and expense, and to repair any damage to the
Demised Premises arising from the installation of or the removal of same, and
should Tenant fail to remove the same, then and in such event the Landlord shall
cause same to be removed at Tenant's sole risk and expense.

                  All of such alterations, decorations, additions or
improvements permitted by Landlord must conform to all rules and regulations
established from time to time by the Underwriters' Association of the local area
and conform to all requirements of Federal, state and local governments. As a
condition precedent to Landlord's consent, Tenant agrees to obtain and deliver
to Landlord written and unconditional waivers of mechanic's and materialmen's
liens upon the land and Building of which Demised Premises are a part, for all
work, labor and services to be performed and materials to be furnished by them
in connection with such work. If, notwithstanding the foregoing, any mechanic's
or materialmen's lien is filed against the Demised Premises, the Building and/or
land, for work claimed to have been done for or materials claimed to have been
furnished to Tenant, such lien shall be discharged by Tenant within ten (10)
days thereafter, at Tenant's sole cost and expense, by the payment thereof or by
filing any bond required by law. If Tenant shall fail to discharge any such
mechanic's or materialmen's lien, Landlord may, at its option, discharge the
same and treat the "cost thereof as additional rent payable with the' monthly
installment of rent next becoming due; it being hereby expressly covenanted and
agreed that such discharge by Landlord shall not be deemed to waive or release
the default of Tenant. Tenant shall also deliver to Landlord prior to the
commencement of any tenant work a builder's risk and general liability policy
naming Landlord as an additional insured with policy limits satisfactory to
Landlord.

            10. SIGNS AND ADVERTISING. Signs, advertising or notice may be
inscribed, affixed or displayed on the outside of the building as approved in
writing in advance by Landlord, such approval not to be unreasonably withheld,
delayed or conditioned and then only in such place, number, size, color and
style as approved by Landlord, and if any such sign, advertisement or notice is
improperly exhibited, Landlord shall have the right to remove the same, and
Tenant shall be" liable for any and all expenses incurred by Landlord by said
removal. Any such permitted use shall be at the sole expense and cost of the
Tenant.

            11. REPAIR OF DAMAGE. All injury to the Demised Premises or the
Building caused by moving any property of Tenant into or out of the Building,
and all breakage done by Tenant or the agents, servants, employees and visitors
of Tenant, shall be repaired by Tenant, at the expense of Tenant. In the event
that Tenant shall fail to do so, then the Landlord shall have the right to make
such necessary repairs, alterations and replacements (structural, non-structural
or otherwise) , and any charge or cost so incurred by the Landlord shall be paid
by Tenant, with the right on the part of the Landlord to elect, in its
discretion, to regard the same as additional rent, in which event such cost or
charge shall become additional rent payable with the

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installment of rent next becoming or thereafter falling due under the terms of
this Lease. This provision shall be construed as an additional remedy granted to
the Landlord, and not in limitation of any other rights and remedies which the
Landlord has or may have in said circumstances.

            12. INSURANCE.

                  (a) Landlord shall insure the Building against damage by fire,
including extended coverage, in any amount Landlord in its sole discretion shall
deem adequate, and shall maintain such insurance throughout the term of this
Lease. Tenant shall fully insure all of its property in the Demised Premises
against damage by fire, extended coverage, vandalism and malicious mischief and
water damage. In addition, Tenant shall also maintain with respect to the
Demised Premises, comprehensive public liability insurance for bodily injury and
property damage naming Landlord as an additional insured, in such amounts as are
adequate to protect Landlord against liability for injury to on death of any
person in connection with the use, operation or Condition of the Demised
Premises. Such insurance at all times shall be in an amount not less that Three
Million Dollars ($3,000,000) for injuries to persons in one accident and not
less than One Million Dollars ($1,000,000) for injury to any one person and not
less than One Million Dollars ($1,000,000) for property damage, which limits may
be increased from time to time to amounts not to exceed those customary for
similarly sized Tenants in the Gaithersburg area.

                  (b) Tenant shall deliver certificates of insurance indicating
the above-specified coverage to the Landlord upon the commencement of the term
of this Lease, and continuing evidence of such coverage annually. Such insurance
policy or policies shall be in a form reasonably satisfactory to the Landlord,
and shall be placed with a company qualified to do business in the jurisdiction
in which the Demised Premises are located, and shall provide that it (they)
cannot be canceled without at least ten (10) days prior written notice to the
Landlord.

                  (c) Neither Landlord nor Tenant shall be liable (by way of
subrogation or otherwise) to the other party (or to any insurance company
insuring the other party) for any loss or damage to any property of the other,
even though such loss or damage might have been occasioned by the negligence of
the Landlord or Tenant, or their respective agents, employees or invitees. This
release shall be in effect only so long as the applicable insurance policies
shall contain a clause or endorsement to the effect that the aforementioned
waiver shall not affect the right of the insured to recover under such policies;
each party shall use its best efforts (including payment of additional premium)
to have its insurance policies contain the standard wavier of subrogation
clause. In the event Landlord's or Tenant's insurance carrier declines to
include a standard waiver of subrogation clause, Landlord or Tenant as the case
may be, shall promptly notify the other party, in which event, the other party
shall not be required to have its insurance policies contain such wavier of
subrogation clause and this paragraph 12(c) shall be of no force and effect.

            13. SERVICES AND UTILITIES. Landlord shall make available
electricity and water servicing the building at Tenant's sole cost. Tenant shall
arrange for the cost of all such utilities to be billed directly to it, and
shall pay all such charges promptly when due. The electrical wiring and other
equipment in the Building are not represented by Landlord to be

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adequate for any particular use and the Landlord does not provide any
uninterruptable power source, power filters or conditioners. Tenant agrees that
it will not make any use of the electrical equipment of the Building which
exceeds the capacity of such equipment. Tenant shall arrange for its own
cleaning service as necessary to keep the Demised Premises in a clean and
orderly condition, and shall separately contract with a trash disposal service
for removal of all trash from the Demised Premises, with storage thereof to be
maintained in a closed dumpster in accordance with applicable law.

            14. DEFAULT. If Tenant shall:

                  (a) Fail to pay any rent or other sum due hereunder at the
time the same shall become due and payable and after ten (10) days' written
notice from Landlord, provided that Landlord shall not be obligated to notify
Tenant of failure to receive the rent more than twice a year during the term of
this Lease, and extension thereof, any subsequent failure to constitute an
immediate event of default;

                  (b) Violate or fail or neglect to keep or perform any of the
covenant's conditions and agreements herein contained on the part of Tenant to
be kept and performed within twenty-one (21) days after written notice to
correct same (which period shall be extended if the same is impractical of cure
within such twenty-one (21) day period and Tenant has commenced and is
diligently pursuing cure) ;

                  (c) Permit the Demised Premises to become vacant or deserted;

            Then Tenant shall be in default hereunder and at the option of the
Landlord, Tenant's right of possession shall cease and terminate, and the
Landlord shall be entitled to possession of the Demised Premises, and Landlord
may proceed to recover possession under and by virtue of the provisions of the
laws of the state in which the Demised Premises are located, or by such other
proceedings, including re-entry and possession as may be applicable, any notice
to quit, or of intention to re-enter the same, being hereby expressly waived by
Tenant. In the event of such re-entry by process of law or otherwise, Tenant
agrees to remain answerable for any and all damage, including, but not limited
to, reasonable attorneys' fees, brokerage fees, and expenses of placing the
Demised Premises in first class rentable condition, deficiency or loss of rent
which the Landlord may sustain by such re-entry, whether or not the Landlord
re-lets the premises, and the Landlord shall have the full power, which is
hereby accepted by Tenant, to re-let the said premises for and on behalf of
Tenant, and upon such-reletting, the Landlord shall have the right each month to
sue for and recover any loss of rents or monthly deficits, with the right
reserved to the Landlord to bring any action(s) or proceeding(s) for the
recovery of any deficits remaining unpaid without being obligated to await the
end of the term of this Lease for a final determination of Tenant's account.
Tenant shall further be liable for and Landlord shall be entitled to prove and
collect the unamortized costs of tenant improvements paid for by Landlord. The
commencement or maintenance of any one or more actions shall not bar the
Landlord from bringing other or subsequent actions for further accruals pursuant
to provisions of this paragraph. Anything to the contrary herein
notwithstanding, Landlord may, at its option, await the expiration of the term
of this Lease before seeking to recover any such deficits, in which event, the
cause of action shall not be deemed to have accrued until the date of expiration
of said term.

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            It is further stipulated and agreed that, in the event of the
termination of the term of this Lease by the happening of any such event, the
Landlord shall become entitled to recover as and for liquidated damages caused
by such breach of the provisions of this Lease, an amount equal to the then cash
value of the difference between the rent reserved hereunder for the unexpired
portion of the term, and the then cash rental value of the Demised Premises for
such unexpired portion of the term hereby, unless the statute which governs or
shall govern the proceeding in which such damages are to be proved limits or
shall limit the amount of such claim capable of being so proved, in which case
the Landlord shall be entitled to prove as and for !liquidated damages in an
amount equal to the maximum amount allowed by or under any such statute. The
provisions of this paragraph of this Lease shall be without prejudice to the
Landlord's right to prove and collect in full damages for rent accrued prior to
the termination of this lease, but not paid. In calculating such liquidated
damages, the then cash rental value of the Demised Premises shall be deemed
prima facia to be the rental realized upon any re-letting, if such re-letting
can be accomplished by the Landlord within a reasonable time after termination
of this Lease. The then cash value of the difference between said cash rental
value of the Demised Premises and the rent reserved hereunder for the unexpired
portion of the term hereby demised shall be deemed to be that principal sum, if
invested at five percent (5%) per annum simple interest, which will yield said
difference, counting said principal sum and interest, over the period of time in
question. Notwithstanding the foregoing, Landlord agrees to use its best efforts
to mitigate any damages it may incur as a result of Tenant's default, provided
that Landlord shall not be required to accept any replacement Tenant deemed by
Landlord to be a substantial credit risk or which Landlord, in its sole
discretion, deems undesirable for the Building.

            In the event of the employment of an attorney by the Landlord or
Tenant because of the violation by the other party of any term or provision of
the Lease, including non-payment of rent as due, the prevailing party shall be
entitled to collect from the other reasonable attorneys' fees and all other
costs incurred therein.

            15. BANKRUPTCY. If the Tenant shall (i) make an assignment for the
benefit of creditors, (ii) be unable to pay its debts as they become due in the
normal course, (iii) or acquiesce in a petition in any court (whether or not,
pursuant to any statute of the United States or of any state) in any bankruptcy,
reorganization, composition, extension, arrangement or insolvency proceedings,
or (iv) make an application in any such proceedings for, or acquiesce in, the
appointment of a trustee or receiver for it, over all or any portion of its
property, or (v) if any petition shall be filed against Tenant in any court
(whether or not pursuant to any statute of the United States or of any state) in
bankruptcy, reorganization, composition, extension, arrangement or insolvency
proceedings, and (i) Tenant shall thereafter be adjudicated a bankrupt or
insolvent, or (ii) such petition shall be approved by any such court, or (iii)
such proceedings shall not be dismissed, discontinued or vacated within sixty
(60) days after such petition is filed; then, in any of said events, this lease
shall immediately cease and terminate, at the option of the Landlord, with the
same force and effect as though the date of occurrence of said event was the day
fixed herein for expiration of the term of this Lease.

            16. NO WAIVER. If under the provisions of this Lease, a compromise
or settlement thereof shall be made, it shall not be considered a waiver of any
breach of any covenant, condition, or agreement herein contained, and no waiver
of any breach of any

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covenant, condition or agreement herein contained shall operate as a waiver of
the covenant, condition or agreement itself, or of any subsequent breach, except
to the extent expressly set forth in the compromise, settlement or waiver. No
payment by Tenant or receipt by the Landlord of a lesser amount than the monthly
installments of rent herein stipulated shall be deemed to be other than on
account of earliest stipulated rent, nor shall any statement by Tenant on any
check, or any letter from Tenant accompanying any check or payment as rent, be
deemed an accord and satisfaction, unless Landlord expressly agrees thereto, and
the Landlord may accept any such check or payment without prejudice to the
Landlord's right to recover the balance of such rent, or to pursue any other
remedy in this Lease. No re-entry by the Landlord, and no acceptance by Landlord
of keys from Tenant, shall be considered an implied acceptance of a surrender of
this lease.

            17. LANDLORD'S CURE OF DEFAULT BY TENANT REIMBURSEMENT OF EXPENSES.
If the Tenant defaults in the making of any payment or in the doing of any act
herein required to be made or done by Tenant, then the Landlord may, but shall
not be required to, make such payment or do such act, and if the Landlord shall
incur any charge or expense on behalf of Tenant under the terms of this Lease,
the amount of the expense thereof, if made or done by the Landlord, shall be
paid by Tenant to Landlord, and shall constitute additional rent hereunder, due
and payable with the monthly installment of rent next due and payable after
Landlord sends a written invoice therefor; provided, however, that the making of
such payment or the doing of such act by the Landlord shall not operate to cure
such default by Tenant, or to estop Landlord from the pursuit of any remedy to
which Landlord would otherwise by entitled.

            18. INSPECTION AND SHOWING OF PREMISES. Tenant agrees that it will
allow the Landlord, its agents or employees, to enter the Demised Premises at
all reasonable times during normal business hours by appointment with an officer
of the Company, without charge therefore to Landlord, and without diminution of
the rent payable by Tenant, to examine, inspect or to protect the same, or to
prevent damage or injury to the same, or to make such alterations and repairs as
the Landlord may deem necessary, and to exhibit the same to prospective tenants
or prospective purchasers during the last six (6) months of the Lease term.

            19. LIABILITY FOR DAMAGE TO PERSONAL PROPERTY- AND PERSON:
INDEMNIFICATION. Landlord shall not be liable for any accident or damage caused
by electric lights or wires, or any accident or damage which may occur through
the operation of heating, electrical or plumbing apparatus, or any accident or
injury occurring in connection with said Building and its services, unless
caused by the gross negligence of Landlord. Landlord will not be liable for loss
of or damage to property of Tenant caused by rain, snow, water or steam that may
leak into or flow from any part of said Building through any defects in the roof
or plumbing or from any other source, not resulting from acts of gross
negligence on the part of Landlord. All goods, property or personal effects
stored or placed by Tenant in or about the Building shall be at the risk of the
Tenant, unless the loss is caused by gross negligence of Landlord.
Notwithstanding any other provisions of this Lease to the contrary, except to
the extent expressly prohibited by law, Tenant hereby waives any claim it might
have against landlord or any partner, officer, director, employee of agent of
Landlord for any consequential damages sustained by Tenant arising out of the
loss or damage to any person or property of Tenant.

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            Each party hereto shall indemnify the other and shall save them
harmless from and against any and all claims, actions, damages, liability and
expense, including reasonable architects' and attorneys' fees, in connection
with loss of life, personal injury and/or damage to property occasioned wholly
or in part by any action or omission of such party, its agents, servants,
employees, assignees or invitees. In case either party shall, without fault on
their part, be made a party(ies) to any litigation commenced by or against the
other, then the other party shall protect and hold them harmless, and shall pay
all costs, expenses and reasonable attorneys' fees incurred or paid by such
party in connection with such litigation.

            20. CONDUCT OF BUSINESS. The Landlord assumes no liability or
responsibility whatever with respect to the conduct and operation of Tenant's
business to be conducted in the Demised Premises, nor with respect to the
conduct and operation of any other use of the Demised Premises which the
Landlord may by prior written consent permit.

            21. DESTRUCTION. In case of damage by fire or other casualty to the
Demised Premises, Tenant shall be required to pay rent covering only that part
of the Demised Premises that remains tenantable; based on the ratio that the
amount of square foot area remaining that can be occupied bears to the total
square foot area of all of the Demised Premises. If during the term of this
Lease the entire Demised Premises or any substantial part thereof shall be so
damaged by fire or other casualty as to be untenantable, then unless said damage
can be repaired within ninety (90) days thereafter as herein specified, either
party hereto, upon written notice to the other party, given at any time
following the expiration of such ninety (90)-day period may terminate this Lease
in which case the rent and additional rent shall be apportioned and paid to the
date of said fire or other casualty. The period of ninety (90) days shall be
extended for such time that Landlord is delayed in substantially completing such
repair or restoration by causes such as strikes, unavailability of materials or
any other cause which is beyond the reasonable control of Landlord. No
compensation or claim or diminution of rent will be allowed or paid, by
Landlord, by reason of inconvenience, annoyance or injury to business, arising
from the necessity may occur, as determined in the sole discretion of Landlord.
Landlord shall have no obligation to replace or repair Tenant's equipment
fixtures or personal property which is to be insured by Tenant. For purposes of
this paragraph, a substantial part shall mean ten percent (10%) or more of the
Demised Premises.

            22. CONDEMNATION. If any portion of the Demised Premises less than a
substantial part thereof shall be taken or condemned or sold for public or
quasi-public use or purpose by or to any competent authority, then this Lease
shall not terminate except as to the part taken and shall terminate as to the
part taken and shall terminate as to the part taken effective as of the date
when title vests in any such authority. Tenant agrees that if the Demised
Premises, or a substantial portion thereof, shall be taken or condemned or sold
for public or quasi-public use or purpose by or to any competent authority, this
Lease shall fully terminate as of the date when the title vests in such
authority. Tenant shall have no claim against the Landlord, and shall not have
any claim or right to any portion of the amount that may be awarded as damages
or paid as a result of any such condemnation; and all rights by Tenant to
damages therefor, if any, are hereby assigned by Tenant to the Landlord.
Provided, however, that Tenant shall have the right to make any separate claim
it may have for damages as a result of such condemnation to the extent that the
same will not reduce the award otherwise payable to Landlord. And upon such
condemnation or taking, the term of this Lease shall cease and terminate as to
the entire Demised

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Premises or the applicable portion thereof from the date when title vests in
such governmental authority, and Tenant shall have no claim against the Landlord
for the value of any unexpired term of this Lease, leasehold improvements or
goodwill. For purposes of this paragraph, a substantial part shall mean ten
percent (10%) or more of the Demised Premises.

            23. ASSIGNMENT AND SUBLETTING.

                  (a) Tenant will not sublet the Demised Premises or any part
thereof, or transfer possession or occupancy thereof , to any person,
partnership, firm or corporation, or transfer or assign this Lease, without the
prior written consent of Landlord, with consent shall not unreasonably be
withheld or delayed, nor shall any subletting or assignment hereof be effected
by operation of law or otherwise than by the prior written consent of Landlord,
which consent shall not unreasonably be withheld or delayed. Any transfer of
interests comprising in excess of fifty percent (50%) of the voting interests in
Tenant shall constitute an assignment. Consent to one assignment, transfer or
subletting to another person, partnership, firm or corporation shall not be
deemed to be a consent to any subsequent assignment, transfer or subletting to
another person, partnership, firm or corporation. Any assignment or subletting
consented to by.-Landlord shall not relieve Tenant of any of its primary
responsibility for all obligations under this lease, and such consent by
Landlord shall not be effective unless and until (i) Tenant gives written notice
thereof to Landlord, and (ii) such transferee, assignee or sublessee shall
deliver to Landlord (a) a written agreement in form and substance satisfactory
to Landlord pursuant to which such transferee, assignee or sublessee assumes all
of the obligations and liabilities of tenant hereunder, and (b) a certified copy
of the assignment agreement or sublease. Any assignment, transfer or subletting
without Landlord's written consent shall be void, and shall, at the option of
Landlord, constitute a default under the terms of this Lease.

            24. HOLDING OVER. In the event that Tenant shall not immediately
surrender the Demised Premises on the date of expiration of the term hereof,
after receipt of written notice from landlord, Tenant shall, by virtue of the
provisions hereof, become a Tenant by the month at a monthly rent equal to the
greater of (i) the then fair market rental value of the Demised Premises or (ii)
one hundred fifty percent (150%) of the monthly rental in effect during the last
month of the term of this Lease, which said monthly tenancy shall commence with
the first day next after the expiration of the terms of this Lease, provided,
however, that Landlord shall not be entitled to increase the rent payable by
Tenant pursuant to this paragraph until thirty (30) days after notice to Tenant
that it intends to do so. The Tenant as a monthly tenant shall be subject to all
of the conditions and covenants of this Lease as though the same had originally
been a monthly tenancy. Tenant shall give to Landlord at least thirty (30) days'
written notice of any intention to quit the Demised Premises, and Tenant shall
be entitled to thirty (30) days' written notice to quit the Demised Premises,
except in the event of nonpayment of rent in advance or of the breach of any
other covenant by the Tenant. Notwithstanding the foregoing, in the event that
Tenant shall hold over after the expiration of the term hereby created, and if
Landlord shall desire to regain possession of the Demised Premises promptly at
the expiration of the term of this Lease, then at any time prior to Landlord's
acceptance of rent from Tenant as a monthly tenant hereunder, Landlord at its
option, may forthwith re-enter and take possession of the Demised Premises
without process, or by any legal process in force in the jurisdiction in which
the Demised Premises are located.

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            25. SUBORDINATION. This Lease is subject and subordinate to any
mortgage and/or deed of trust (which terms shall include both construction and
permanent financing) which may now or hereafter encumber or otherwise affect the
Demised Premises, and to all renewals, extensions, modifications,
consolidations, replacements, recasting and/or refinancings thereof. This clause
shall be self-operative, and no further instrument of subordination shall be
required by any mortgagee or trustee to effect the subordination of this Lease.
Nonetheless, in confirmation of such subordination, Tenant shall, at Landlord's
request, within five (5) days after delivery to Tenant, execute any reasonably
requisite or appropriate certificate or document. Tenant agrees that in the
event that any proceedings are brought for the foreclosure of any such mortgage,
Tenant shall attorn to the purchaser at such foreclosure sale, if requested to
do so by such purchaser, and to recognize such purchaser as the Landlord under
this Lease, and Tenant waives the provisions of any statute or rule of law, now
or hereafter in effect, which may give or purport to give Tenant any right to
terminate or otherwise adversely affect this Lease and the obligations of Tenant
hereunder. In the event that Tenant fails to deliver such document to Landlord
within the time periods required above, Tenant hereby appoints Landlord its
Attorney-in-fact for the limited purpose of executing and delivering such
documents.

            26. ESTOPPEL CERTIFICATES. Tenant agrees, at any time and from time
to time, upon not less than five (5) days prior written notice by Landlord, to
execute, acknowledge and deliver to Landlord, a statement in writing (i)
certifying that this Lease is unmodified and in full force and effect, or, if
there have been modifications, that this Lease is in full force and effect as
modified, and stating any such modifications; (ii) certifying that Tenant has
accepted possession of the Demised Premises, and that any improvements required
by the terms of this Lease to be made by the Landlord have been completed to the
satisfaction of the Tenant, or if such improvements have not been made,
specifying those that have not; (iii) stating that no rent under this Lease has
been paid more than thirty (30) days in advance of its due date; (iv) stating
the address to which notices to Tenant should be sent; (v) certifying that
Tenant, as of the date of any such certification, has no charge, lien or claim,
of set-off under this Lease, or otherwise, against rents or other charges due or
to become due hereunder; and (vi) stating whether or not, to the best of
Tenant's knowledge, 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 have knowledge. Any such statement delivered
pursuant hereto may be relied upon by any owner of the Building, any prospective
purchaser of the Building, any mortgagee or prospective mortgagee of the
Building or of Landlord's interest, or any prospective assignee c >f any such
mortgagee. In the event that Tenant fails to deliver such document to Landlord
within the time periods required above, Tenant hereby appoints Landlord its
Attorney-in-fact for the limited purpose of executing and delivering such
documents.

            27. NOTICES. All notices required or desired to be given hereunder
by either party to the other shall be hand delivered, or given by certified or
registered mail, first-class postage prepaid, return receipt requested. Notice
to the respective parties shall be addressed as follows:

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            If to the Landlord:

                Richard Dietrick
                14727 Crossway Road
                Rockville, MD 20853

            with a copy to:

                Lawrence S. Stern, Esq.
                4550 Montgomery Avenue, #775N
                Bethesda, MD 20814

            If to the Tenant:

                Prior to the Commencement Date

                Leet-Melbrook, Inc.
                9319 Gaither Road
                Gaithersburg, Maryland 20977

                After the Commencement Date

                Leet-Melbrook, Inc.
                18810 Woodfield Rd.
                Gaithersburg, Maryland 20879

            Either party may, by like written notice, designate a new address to
which such notices shall be directed. Notice shall be deemed received three (3)
days after given as provided herein, or when actually received, whichever is
earlier.

            28. NO PARTNERSHIP. Nothing contained in this Lease shall be deemed
or construed to create a partnership or joint venture of or between Landlord and
Tenant, or create any other' relationship between the parties hereto other than
that of Landlord and Tenant.

            29. NO REPRESENTATIONS BY LANDLORD. Neither Landlord nor any agent
or employee of Landlord has made any representations or promises, with respect
to the Demised Premises or the Building except as herein expressly set forth,
and no rights, privileges, easements or licenses are acquired by Tenant except
as herein set forth. The Tenant by taking possession of the Demised Premises,
shall accept the same "as is." Such taking of possession shall be conclusive
evidence that the Demised Premises and the Building are in good and satisfactory
condition at the time of such taking of possession.

            30. BROKERAGE. Landlord and, Tenant each represent that they had no
dealings with any real estate broker, finder or other person, with respect to
this Lease in any manner, except McShea. Landlord and Tenant agree to indemnify
and hold each other harmless against and from any claims for any brokerage
commission or other fees and all costs, expenses and liabilities in connection
therewith, including, without limitation, attorneys' fees and expenses, arising
out of any dealings by Tenant with any other broker. Landlord shall pay any

                                       12

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commissions or fees that are payable to McShea with respect to this Lease, in
accordance with the provisions of a separate commission contract.

            31. WAIVER OF TRIAL BY JURY. Except as prohibited by applicable law,
the parties hereto shall, and they hereby do, waive trial by jury in any action,
proceeding or counterclaim brought by either of the parties hereto against the
other on any matters whatsoever arising out of or in any way connected with this
Lease, the relationship of Landlord and Tenant, Tenant's use and occupancy of
the Demised Premises and/or any claim of injury or damage. In the event the
Landlord commences any proceedings for non-payment of rent, minimum rent or
additional rent, Tenant will not interpose any counterclaim of whatever nature
or description in any such proceedings. This shall not, however, be construed as
a waiver of Tenant's right to assert such claims in any separate action brought
by Tenant.

            32. QUIET ENJOYMENT. Upon payment by Tenant of all items of rent,
additional rent, and any and all other sums to be paid by Tenant to Landlord
hereunder, and the observance and performance of all of the covenants, terms and
conditions to be observed and performed by Tenant, Tenant shall have the
peaceful and quiet use of the Demised Premises, and all rights, servitude and
privileges belonging, or in any way pertaining thereto or granted hereby, for
the term of this Lease, without hindrance or interruption by Landlord, or any
other person or persons lawfully claiming by, through or under Landlord, subject
nevertheless to the terms and conditions of this Lease, and to any mortgage,
deed of trust, ground lease or agreement to which this Lease, and/or Landlord's
interest in the Demised Premises and the Building of which they are a part, is
subordinate. Landlord warrants that it has full right and authority to enter
into this Lease for the full term hereof.

            33. BINDING EFFECT OF LEASE. It is agreed that all rights, remedies
and liabilities herein given to or imposed upon either of the parties hereto,
shall extend to their respective heirs, executors, administrators, and except as
otherwise expressly provided in this Lease, their successors and assigns.
Landlord may freely and fully assign its interest hereunder. The term "Landlord"
shall mean only the owner at the time in question of the Building or of a lease
of the building, so that in the event of any transfer or transfers of title to
the Building or of Landlord's interest in a lease of the Building, the
transferor shall be and hereby is relieved and freed of all obligations of
Landlord under this Lease accruing after such transfer, and it shall be deemed,
without further agreement, that such transferee has assumed and agreed to
perform and observe all obligations of Landlord herein during the period it is
the holder of Landlord's interest under this Lease.

            Neither party shall be required to perform any of its obligations
under this Lease, nor be liable for loss damage for failure to do so, where such
failure arises from or through acts of God, strikes, lockouts, labor
difficulties, explosions, sabotage, accidents, riots, civil commotions, acts of
war, results of any warfare or warlike conditions in this or any foreign
country, fire and casualty, legal requirements, energy shortage, or causes
beyond the reasonable control of such party, unless such loss or damage results
from willful misconduct or negligence by such party or its employees. This
paragraph shall under no circumstances apply with respect to any obligation to
make payments of rent or other amounts due hereunder.

                                       13

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            34. APPLICABLE LAW AND CONSTRUCTION. The laws of the jurisdiction in
which the Demised Premises are located shall govern the validity, performance
and enforcement of this Lease. If any provision of this Lease shall at any time
be deemed to be invalid or illegal by any court of competent jurisdiction, this
Lease shall not be invalidated thereby; and in such event, this lease shall be
read and construed as if such invalid or illegal provision only had not been
contained herein, thereby preserving all or the other terms, conditions and
provisions of this Lease.

            35. GENDER. Feminine or neuter pronouns shall be substituted for the
masculine form, and the plural substituted for the singular number, in any place
or places herein which the context may require such substitution or
substitutions. The Landlord herein for convenience has been referred to in
neuter form.

            36. PARKING. Tenant shall have exclusive use of the parking areas
pertinent to the Demised Premises which currently consist of approximately 60
parking spaces.

            37. ENTIRE AGREEMENT. This Lease, together with accompanying
Exhibits, contains the entire and only agreement between the parties and no oral
statements or representations or prior written matter not contained or referred
to in this instrument shall have any force or effect. This Lease shall not be
modified in any way except by a writing subscribed by both parties hereto. The
failure of the Landlord to insist upon strict performance by the Tenant of any
of the covenants or conditions of this Lease in any one or more instances shall
not be construed as a waiver or relinquishment for the future of any such
covenants or conditions, but the same shall be and remain in full force and
effect. No waiver of any provision of this Lease shall be deemed to have been
made, unless it be in writing and signed by the party to be charged therewith.

            38. Right of First Refusal.

                  Continuing while the Lease remains in effect, in the event
that Landlord receives a bona fide offer for the purchase of the Building, which
offer Landlord would like to accept, Landlord shall notify Tenant, in writing,
and furnish to Tenant a copy of such bona fide offer. Tenant shall then have a
period of ten (10) days within which to elect to purchase the Building at the
same price and terms that are contained in the bona fide offer. Such election
must be made in writing within such ten (10) day period. In the event that
Tenant exercises its option to purchase the Building within the required time
period, then Landlord shall sell, and Tenant shall purchase, the Building
pursuant to the terms of the bona fide offer. If Tenant has not so exercised its
option to purchase the Building within the required time period, then Landlord
shall be free to consummate the sale of the Building to the party making the
bona fide offer pursuant to the price and terms of the bona fide offer.

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            IN WITNESS WHEREOF, the undersigned have executed this Lease
effective the date first above written.

WITNESS:                                  LANDLORD: /s/ RICHARD L. DIETRICK

                                        BY: /s/ GARNETTA J. DIETRICK
__________________________________          ------------------------------
                                            LEET-MELBROOK, INC.
ATTEST:

/s/ EILEEN M. HALEY                     BY: /s/ JAMES E. PENROD
----------------------------------          ------------------------------
SECRETARY                                   PRESIDENT

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                                    EXHIBIT A

                          TENANT'S INITIAL ALTERATIONS

                                       16