Lease Renewal Addendum Number One
Software Technology, Inc.
                                                                   Exhibit 10.10


                    ADDENDUM NUMBER ONE TO AGREEMENT OF LEASE
                                 BY AND BETWEEN
            HUNTING CREEK, LLC, A Delaware limited liability company
            (Formerly Alexandria South Associates, L.P.) AS LANDLORD

                                       AND

           SOFTWARE TECHNOLOGY, INC., A Florida Corporation, AS TENANT

         The above referenced Agreement of Lease dated August 15, 1994 is hereby
amended and modified in the following manner:


1.   TERM - - Five  (5)  years  beginning  on  September  1,  1998,  the  "Lease
     Commencement  Date" and ending on August 31,  2003,  the "Lease  Expiration
     Date." 2. BASE  ANNUAL RENT - - It is agreed that  effective  September  1,
     1998,  the base annual rent shall be Two Hundred  Ninety Four Thousand Four
     Hundred  Forty  Eight and 00/100  Dollars  ($294,448.00),  payable in equal
     monthly  installments of Twenty Four Thousand Five Hundred Thirty Seven and
     33/100 Dollars  ($24,537.33) subject to annual escalations and passthroughs
     per the existing  Agreement of Lease. 3. ADDITIONAL RENT - - Pro rata share
     of Operating  Expense  increases  over the Operating  Expense Amount of the
     Base Year 1999.  4. TENANT  IMPROVEMENTS  - - Landlord  shall  provide,  at
     Landlord's expense,  reconfiguration of the Premises in accordance with the
     plan attached as Exhibit "A" prepared by Architecture & Design  Associates,
     Inc.  dated May 18, 1998 and  approved  by Tenant on May 29, 1998  ("Tenant
     Approved Plans") utilizing Building standard materials and specifications.

     All Building HVAC,  fire and life safety code  requirements  (including but
     not limited to sprinklers,  exit signs, heatpumps,  and VAV boxes) shall be
     installed  and/or  relocated  as  required  by  "Exhibit  A" at  Landlord's
     expense.  The  Tenant's  Premises  shall be  constructed  or  modified  per
     "Exhibit  A", at  Landlord's  sole  cost and  expense,  to comply  with the
     requirements  of the Americans  with  Disabilities  Act standards  (ADA) as
     required at time of construction permit issuance.  NOTE:  Alteration and/or
     installation  of phone,  computer  equipment  and cabling shall be excluded
     from said Tenant Improvements provided by Landlord.

5.   TERMINIATION  OF LEASE - - Article  21(b)(i) is hereby null and void and is
     replaced by the following verbiage:

     Landlord may terminate  this Lease by giving notice of such  termination to
     Tenant, a) if Tenant is in default due to failure to pay Monthly Payment(s)
     or  Additional  Rent when due and Tenant fails to cure such default  within
     ten (10) days after such notice is received;  or b) if Tenant fails to cure
     any  non-monetary  default within thirty (30) days after such notice (which
     thirty (30) day period shall be extended for such additional period of time
     as  reasonably  may be necessary to cure such default if by its nature such
     default  cannot  be  cured in such  thirty  (30)  day  period,  so long as,
     however, Tenant shall commence to cure such default within such thirty (30)
     day period and shall proceed diligently to cure same);  PROVIDED,  HOWEVER,
     that this Subparagraph may not be invoked while a case under the Bankruptcy
     Code is pending in which Tenant is the subject debtor, unless Tenant or its
     Trustee  in  Bankruptcy  is  unable  to  comply  with  the   provisions  of
     Subparagraph 21 (b)(vi), 21 (b)(vii),  and 21 (b)(vii).  Upon the giving of
     notice and failure of Tenant to cure within the above-prescribed time, this
     Lease shall  terminate  and Tenant shall be obligated to quit and surrender
     the Premises. Any other notice to quit or notice of Landlord's intention to
     re-enter  is hereby  expressly  waived by  Tenant.  If  Landlord  elects to
     terminate this Lease under these  provisions,  all covenants and agreements
     herein  made by  Landlord  shall cease  without  prejudice  to the right of
     Landlord to recover from Tenant all rent accrued to the time of termination
     or recovery of possession of the Premises by Landlord,  whichever is later,
     and any other monetary  damages or loss  sustained by Landlord,  including,
     but not  limited  to,  loss of  rent,  costs of  advertising,  commissions,
     physical alterations, and rent concessions of any kind.

6.   TENANT'S  FINANCIAL DATA - - Article 32(o) is amended to provide any needed
     or requested  financial  data  regarding  Tenant or entities or individuals
     related to Tenant will be acquired by Landlord from Tenants' public filings
     with  the  Securities  and  Exchange  Commission.   Tenant  shall  have  no
     obligation  to  provide  information  in excess of or  addition  to the SEC
     public filings.

7.   SIGNAGE - - Article 36 is hereby  amended to provide  Tenant,  at its costs
     and expense,  the right,  during the Term and any  extensions  thereto,  to
     modify and/or  replace any existing  Tenant signage on the Penthouse of the
     Building  which  signage  shall be mutually  agreeable to both Landlord and
     Tenant. The  specifications  for any such modifications  and/or replacement
     must meet existing  Fairfax County Zoning  Regulations and shall be defined
     and shall be incorporated as an addendum to the Lease.

8.   OPTION TO EXTEND - - Article 38 "Option to Extend" is hereby  null and void
     and is replaced by the following:

     Provided  the Tenant is not in default of its Lease  terms and  conditions,
     Tenant  shall have the right to extend  the lease for three (3)  additional
     one (1) year terms at  ninety-five  percent  (95%) of the then current fair
     market  rate,  as mutually  agreed upon by Landlord  and Tenant,  but in no
     event shall the renewal rate be less that the Tenant's then current  rental
     rate in effect at the  expiration  of the current  term.  Tenant shall give
     Landlord no less than one hundred  eighty (180) days written  notice of its
     intent to exercise said option to renew.

9.   OPTION TO CONTRACT - - Article 39 "Reduction to Size of Premises" is hereby
     null and void and is replaced by the following verbiage:

     Provided the Tenant is not in default of Lease terms and conditions, at any
     time during the last three (3) years of the renewal term, Tenant shall have
     the right to "give back" to the Landlord up to 4,106  rentable  square feet
     of space by  providing  Landlord  with one hundred  eighty (180) days prior
     written notice  accompanied by liquidated damages in an amount equal to one
     hundred twenty five percent (125%) of the unamortized brokerage commissions
     and Tenant Improvements on a pro-rata basis as applied to the actual square
     footage  contracted  amortized at ten percent (10%) interest per annum. The
     total  cost of  commissions  is  $73,612.00  and the  total  cost of Tenant
     Improvements is  $173,700.00.  Such right to contract shall continue during
     Tenant's  renewal periods.  In the event Tenant elects to contract,  Tenant
     shall forgo its right of Building signage.

10.  RIGHT OF FIRST  OFFER - -  Provided  the  Tenant is not in  default  of the
     Lease, Tenant shall have the first of offering to lease any space available
     in the Building  (Expansion Area),  subject to expansion rights, if any, of
     existing  tenant(s).   Tenant  shall  have  five  (5)  business  days  from
     Landlord's written offer to lease the then available  Expansion Area at the
     terms provided by Landlord in the Landlord's offer. Should Tenant elect not
     to lease the Expansion  Area(s),  Landlord shall be relieved of any further
     obligation  to  Tenant  and  Landlord  shall be free to lease  the  offered
     Expansion Area(s) to other tenant(s). However, in the event the Landlord is
     willing to accept an offer for the  Expansion  Area(s) at terms  materially
     less  advantageous to Landlord than the terms contained in Landlord's offer
     to Tenant, then Landlord shall advise Tenant of such terms and Tenant shall
     have five (5) business days from  Landlord's  notice to lease the available
     Expansion Area at the terms then deemed acceptable by Landlord.

11.  SUBLEASING  AND  ASSIGNMENT - - The  provisions  of Article 12 of the Lease
     notwithstanding,  fifty  percent  (50%) of any net profits from  subleasing
     shall be retained by the Landlord and fifty percent (50%) shall be retained
     by Tenant. Landlord will provide to subtenant(s) and assignee(s) all rights
     and services provided for in Tenant's lease.

12.  ROOF RIGHTS - - Tenant shall have reasonable access to and use of a portion
     of the  Building  roof at no charge to Tenant,  specific  location to be by
     mutual  agreement,  subject to local government codes and coordination with
     Building   management  for  the   installation   and   maintenance  of  its
     communication  equipment  throughout the term and any  extensions  thereof.
     Tenant shall  obtain all required  permits and submit plans to Landlord for
     review and approval prior to  installation.  Upon  expiration of the Lease,
     Tenant shall remove its  communication  equipment from the roof at Tenant's
     sole expense,  including  making all required  roof repairs.  All roof work
     required  to  install  and  remove  said  dishes  shall be  performed  by a
     Landlord-approved contractor so as not to void any existing roof warranty.

13.  NON-DISTURBANCE/QUIET  ENJOYMENT - - Landlord shall use its best efforts to
     obtain a non-disturbance  agreement from its current lender and from future
     lenders,   which  shall  not  allow  for  the  early   termination  or  any
     modification  of the Lease and its various  extensions  and options.  In no
     event  shall this Lease be void or  voidable  should  Landlord's  lender(s)
     refuse to supply a non-disturbance agreement.

14.  LANDLORD'S ADDRESS FOR NOTICES - -

Landlord's Address for Notice:              Hunting Creek, LLC
                                            ATTN:  William B. Fetsch, Manager
                                            6535 Copa Court
                                            Falls Church, Virginia  22044-1401

With a Copy to:                             Gates, Hudson & Associates, Inc.
                                            3020 Hamaker Court
                                            Suite 301
                                            Fairfax, Virginia 22031

Notice to Tenant:                           Dr. C. Camden McCarl
                                            Manager of DC Engineering
                                            Software Technology, Inc.
                                            5904 Richmond Highway, Suite 610
                                            Alexandria, Virginia 22303

                                            Mr. Stuart P. Dawley
                                            General Counsel
                                            Exigent International, Inc.
                                            1225 Evans Road
                                            Melbourne, Florida  32904-2314
                                            Fax: (407) 952-7555

15.  HAZARDOUS  MATERIALS  REPRESENTATION  - - Landlord  represents and warrants
     that the air within the Premises, and any associated common areas, is free,
     and shall remain free during the term of the Lease,  of any  concentrations
     of asbestos or any other hazardous materials that violate federal, state or
     local  regulations or ordinances or present a health threat to Tenant,  its
     employees  or  agents,  ("Hazardous  Materials").   Tenant  represents  and
     warrants that it will not use Hazardous Materials in or about the Premises.

16.  COMMISSION - - The Fred Ezra Company (Broker) is acting solely as agent for
     the Tenant in this  lease  transaction,  with a  fiduciary  duty  solely to
     Tenant. Broker is not acting as agent for the Landlord in this transaction,
     however,  Tenant is not liable for the payment of brokerage  commissions to
     either Gates, Hudson & Associates, Inc., or the Fred Ezra Company. Landlord
     recognizes  The  Fred  Ezra  Company  as the  cooperating  broker  in  this
     transaction  and  will  compensate  the  Broker  with a  market  commission
     according to a separate agreement.


<PAGE>

             ALL OTHER TERMS AND CONDITIONS OF THE ABOVE REFERENCED
            AGREEMENT OF LEASE SHALL REMAIN IN FULL FORCE AND EFFECT

WITNESS AS TO LANDLORD:                       LANDLORD:  HUNTING CREEK, LLC


/s/ Robin B. Fetsch                           BY: /s/ William B. Fetsch
----------------------------                      ------------------------------
(Corporate Seal)                                 DATE: 31 - July 1998


ATTEST AS TO TENENT:                          TENANT:  SOFTWARE TECHNOLOGY, INC.
                                                       A FLORIDA CORPORATION

/s/ Don F. Riordan, Jr.                        BY: /s/ B.R. Smedley
----------------------------                      ------------------------------
(Corporate Seal)
                                                  PRINTED NAME: B.R. Smedley
                                                                ----------------
                                                  TITLE: President
                                                         -----------------------
                                                  DATE:  22 - July 1998
                                                         -----------------------


APPROVED FOR GATES, HUDSON & ASSOCIATES, INC.


BY: /s/ Jeffrey G. Weaver, Sr. V.P.
    ---------------------------------