THIS SEVENTH  SUPPLEMENTAL  INDENTURE (this "Supplemental  Indenture"),
dated as of May 23, 2003, among Anteon International Corporation (formerly known
as Azimuth Technologies,  Inc.), a Delaware corporation (the "Company"), and The
Bank of New York (as successor to IBJ  Whitehall  Bank & Trust  Company),  a New
York banking corporation as trustee (the "Trustee").

         WHEREAS, the Company, Anteon Corporation (formerly known as Techmatics,
Inc.), a Virginia  corporation  and a subsidiary  guarantor,  CITI-SIUSS  LLC, a
Delaware corporation and a subsidiary guarantor,  South Texas Ship Repair, Inc.,
a Virginia corporation and a subsidiary  guarantor,  and the Trustee are parties
to an Indenture,  dated as of May 11, 1999, as  supplemented,  providing for the
issuance  of  the  Company's  12%  Senior   Subordinated  Notes  due  2009  (the
"Indenture");

         WHEREAS, on the date hereof, the Company has acquired all of the issued
and  outstanding  common  stock of  Information  Spectrum,  Inc.,  a New  Jersey
corporation  ("ISI"), and accordingly,  ISI became a wholly-owned  subsidiary of
the Company;

         WHEREAS,  pursuant  to Section  4.10 of the  Indenture,  ISI,  as a new
Restricted Subsidiary,  is required to enter into this Supplemental Indenture as
a Subsidiary Guarantor;

         WHEREAS,  the Company, ISI and the Trustee are authorized to enter into
this Supplemental Indenture;

         NOW, THEREFORE, for and in consideration of the premises and the mutual
covenants  contained  in this  Supplemental  Indenture  and for  other  good and
valuable  consideration,  the  receipt  and  sufficiency  of  which  are  herein
acknowledged,  the Company,  ISI and the Trustee  hereby agree for the equal and
the ratable benefit of all Holders of the Securities as follows:

                                   ARTICLE ONE

                                   Definitions

1.1 Definitions.  For purposes of this Supplemental Indenture, the terms defined
in the recitals shall have the meanings therein specified;  any terms defined in
the  Indenture  and not defined  herein shall have the same  meanings  herein as
therein  defined;  and  references  to Articles or  Sections  shall,  unless the
context  indicates  otherwise,  be  references  to  Articles  or Sections of the
Indenture.

                                   ARTICLE TWO

                   Guaranty Of Securities And Other Provisions

2.1      ISI Guarantee

                           a)  ISI  hereby   unconditionally   and   irrevocably
guarantees, jointly and severally, to each
Holder  and to the  Trustee  and its  successors  and  assigns  (i) the full and
punctual  payment of  principal  of and  interest  on the  Securities  when due,
whether at maturity, by acceleration,  by redemption or otherwise, and all other
monetary  obligations of the Company under this Indenture and the Securities and
(ii) the full and punctual  performance  within  applicable grace periods of all
other obligations of the Company under the Indenture and the Securities (all the
foregoing being hereinafter collectively called the "Obligations").  ISI further
agrees that the  Obligations  may be  extended or renewed,  in whole or in part,
without  notice or further  assent from ISI and that ISI will remain bound under
this Section notwithstanding any extension or renewal of any Obligation.

                           b) ISI, the Trustee and each Holder by its acceptance
of a Security hereby agrees that the
Subsidiary  Guaranty of ISI  provided  hereunder  shall be subject to all terms,
provisions and conditions in the Indenture that relate to a Subsidiary  Guaranty
(including,  without  limitation,  Articles  11 and 12 of  the  Indenture).  ISI
further  agrees  to be bound by,  and to  comply  with,  all  provisions  of the
Indenture  and  Subsidiary   Guarantee  that  are  applicable  to  a  Subsidiary
Guarantor.

2.2      Execution and Delivery of Subsidiary Guaranties

The delivery of any Security by the Trustee,  after the  authentication  thereof
under the Indenture, shall constitute due delivery of the Subsidiary Guaranty on
behalf of ISI.

2.3      No Personal Liability

No stockholder,  officer, director,  employee or incorporator,  past, present or
future, of ISI, as such, shall have any personal  liability under the Subsidiary
Guaranty  of ISI by  reason  of his,  her or its  status  as  such  stockholder,
officer, director, employee or incorporator.

                                  ARTICLE THREE

                                  Miscellaneous

3.1      Effect of the Supplemental Indenture

This  Supplemental  Indenture  supplements the Indenture and shall be a part and
subject to all the terms thereof.  Except as supplemented  hereby, the Indenture
and the Securities issued thereunder shall continue in full force and effect.

3.2      Counterparts

This Supplemental Indenture may be executed in counterparts, each of which shall
be deemed an original,  but all of which shall  together  constitute one and the
same  instrument.  The parties hereto confirm that any facsimile copy of another
party's executed  counterparts of this Supplemental  Indenture (or its signature
page hereof) will be deemed to be an executed original thereof.

3.3      GOVERNING LAW.
         -------------

THIS  SUPPLEMENTAL  INDENTURE  SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK.



<PAGE>



         IN WITNESS  WHEREOF,  the parties hereto have caused this  Supplemental
Indenture to be duly executed on the date first above written.



                        ANTEON INTERNATIONAL CORPORATION

                      By:_________________________________

                          Name: Joseph Kampf
                          Title:   President and Chief Executive Officer




                        INFORMATION SPECTRUM, INC.

                      By:_________________________________

                          Name:  Curtis Schehr
                          Title:   Vice President



                        THE BANK OF NEW YORK, as Trustee



                      By:_________________________________

                          Name:
                          Title: