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                                                                   EXHIBIT 10.30



               SECOND AMENDMENT TO STORAGE SPACE RENTAL AGREEMENT


         THIS SECOND AMENDMENT TO STORAGE SPACE RENTAL AGREEMENT (this "Second
Amendment") is made and entered into this 28th day of August, 1998, by and
between HYATT PLAZA LIMITED PARTNERSHIP, a Virginia limited partnership (the
"Landlord") and XYBERNAUT CORPORATION, a Delaware corporation, formerly known
as Computer Products and Services, Inc. (the "Tenant"), with reference to the
following:

                                    RECITALS

         A.      Landlord leased to Tenant certain Premises (as defined
therein) pursuant to the terms and conditions of that certain Office Lease
Agreement dated November 1, 1994 (the "Original Lease"), as amended by (i) that
certain First Amendment to Office Lease Agreement dated July 1, 1997 (the
"First Amendment") and (ii) that certain Second Amendment to Office Lease
Agreement dated April 30, 1998 (the "Second Amendment") (the Original Lease,
First Amendment and Second Amendment are hereinafter collectively referred to
as the "Lease").

         B.      Pursuant to that certain Storage Space Rental Agreement dated
as of January 15, 1997 (the "Original Agreement"), as amended by that certain
First Amendment to Storage Space Rental Agreement dated September 2, 1997 (the
"First Amendment") (the Original Agreement and First Amendment are hereinafter
collectively referred to as the "Agreement") by and between Landlord and
Tenant, Landlord leased to Tenant certain storage space more particularly
described therein in the building commonly known as Hyatt Plaza, 12701 Fair
Lakes Circle, Fairfax, Virginia 22033 (the "Building"). All capitalized terms
used herein unless specifically defined shall have the same meaning and
definition as used in the Agreement.

         C.      Landlord and Tenant desire to amend the Agreement as more
particularly described herein.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, Landlord and Tenant agree as
follows:

         1.      All capitalized terms used herein, unless specifically defined
herein, shall have the same meaning and definition as used in the Agreement.


         2.      Landlord and Tenant desire to extend the Term for an
additional five (5) year period (the "Extension Term"), commencing as of
October 1, 1998 (the "Extension Term Commencement Date") and expiring
co-terminously with the Lease.

         3.      Tenant agrees to accept the Storage Space for the Extension
Term in its "as is" and "where is" condition, and Landlord will have no
obligation to make any improvements or modifications to the Storage Space.





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         4.      Landlord and Tenant agree that the Base Rent for the Extension
Term shall be $7,505.50 per year ($624.46 per month), based on $8.50 per square
foot of Rentable Area in the entire Storage Space (883 rentable square feet),
subject to adjustment pursuant to Section 4.02 of the Agreement.

         5.      During the Extension Term, the Rental Adjustment Date defined
in Section 4.02 of the Agreement shall be changed to October 1st and the first
Rental Adjustment Date of the Extension Term shall be October 1, 1999.

         6.      Except as expressly modified by this Second Amendment, the
Agreement remains unchanged and in full force and effect.


         IN WITNESS WHEREOF, Landlord and Tenant have executed this Second
Amendment as of the day and year first above written.


                              LANDLORD:
                              --------

                              HYATT PLAZA LIMITED PARTNERSHIP
                              a Virginia limited partnership


                              By:      FAIR LAKES HYATT LIMITED
                                       PARTNERSHIP, a Virginia limited
                                       partnership, its general partner

                              By:      Fair Lakes of Virginia, Inc., a Virginia
                                       corporation, its general partner


                              By:          /s/ MILTON V. PETERSON
                                       ---------------------------------
                              Name:         MILTON V. PETERSON
                                       ----------------------------------
                              Title:             PRESIDENT
                                       ---------------------------------


                              TENANT:
                              ------

                              XYBERNAUT CORPORATION, formerly known as
                              Computer Products and Services, Inc.
                              a Delaware corporation

                              By:                /s/ E. NEWMAN
                                       ---------------------------------
                              Name:                  E. NEWMAN
                                       ---------------------------------
                              Title:             PRESIDENT
                                       ---------------------------------





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