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                                                                EXHIBIT 10.17


                              SUBLEASE AGREEMENT

     This Sublease is made this 3/rd/ day of December, 1996 at Travis County,
Texas by and between Progressive System Technologies, Inc., (herein,
"Sublessor"), and Group, Inc., (herein, "Sublessee").

     Sublessor is the Lessee under that certain Lease, (the "Main Lease"), by
and between SL-6 PARTNERS, LTD. as Landlord, (herein, "Lessor"), and Progressive
System Technologies, Inc., as Tenant, (herein "Sublessor"), executed on or about
November 20, 1995, for the premises described in the Main Lease, (herein,
"Leased Premises"), a true and correct copy of which Main Lease is attached
hereto as Exhibit "B" and incorporated herein by this reference.

     In consideration of the mutual promises contained herein, Sublessor hereby
subleases a portion of the Leased Premises to Sublessee as further described
below, subject to the terms of the Main Lease, and subject further to the
provisions of this Sublease Agreement, as follows:

     1.   Sublessor hereby leases to Sublessee, and Sublessee hereby takes from
          Sublessor approximately 21,600 square feet of the Leased Premises
          (herein "Sublease Space") in the building known locally as Stonelake
          #6 located at 11000 North Mopac Expressway, Austin, Texas 78759 as
          shown on Exhibit "A" attached hereto and a part hereof.

     2.   Sublessee hereby takes the Sublease Space subject to any mortgages or
          deeds of trust to the same extent that Sublessor holds the Leased
          Premises as set forth in paragraph 21 of the Main Lease and Sublessee
          agrees to abide by and observe all the terms, covenants and conditions
          of the Main Lease.

     3.   The term of this Sublease shall be for a term of thirty six (36)
          months, commencing on February 1, 1997, and ending January 31, 2000,
          provided, however, that this Sublease shall sooner terminate upon the
          termination for any cause whatsoever of the Main Lease, and as further
          provided for below. In the event that the tenant improvements are not
          substantially complete, but for delays caused directly or indirectly
          by Sublessee, and ready for occupancy by January 31, 1997, then the
          rent during the first month of the lease term shall be appropriately
          abated and pro-rated. Sublessor agrees to negotiate, to the best of
          its ability, with the contractor selected to build the tenant
          improvements, provisions for said contractor to pay liquidated damages
          to Sublessor in the event the tenant improvements are not
          substantially complete by January 31, 1997. In such event, Sublessor
          agrees to pass through any and all liquidated damages collected to
          Sublessee upon collecting same from the contractor.

     4.   Insofar as the provisions of the Main Lease do not conflict with the
          specific provisions of this Sublease Agreement, they and each of them
          are incorporated into this Sublease as if fully completely rewritten
          herein, and Sublessee agrees to be bound to the Sublessor by all the
          terms of the Main Lease and to assume towards Sublessor and perform
          all the obligations and responsibilities that Sublessor, by the Main
          Lease, assumes towards the Lessor, except for the

                                      1.
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          payment of rent by Sublessee to Sublessor, which is governed by
          Paragraph 5 herein. However, some provisions of the Main Lease shall
          specifically be modified from the terms of the Main Lease and/or not
          be incorporated into this Sublease Agreement as follow:

          (a)  Paragraph 1.A, Building or Improvements to be Constructed shall
                              ------------------------------------------
               be modified by replacing the provisions for liquidated damages
               with the following: Sublessor agrees to negotiate, to the best of
               its ability, with the contractor selected to build the tenant
               improvements, provisions for said contractor to pay liquidated
               damages to Sublessor in the event the tenant improvements are not
               substantially complete by January 31, 1997. In such event,
               Sublessor agrees to pass through any and all liquidated damages
               collected to Sublessee upon collecting same from the contractor.

          (b)  Paragraph 10.D, Alternative Space, of the Main Lease shall not be
                               -----------------
               incorporated herein;

          (c)  Paragraph 11.D, Liability and Indemnification, shall be modified
                               -----------------------------
               by adding the following language: Except for any claims, rights
               of recovery, and causes of action that Sublessee has released, or
               that are caused in whole or in part by the gross negligence or
               willful misconduct of Sublessee, Sublessor shall hold Sublessee
               harmless from and defend Sublessee against any and all claims or
               liability including without limitation reasonable attorney's fees
               and court costs raised against or suffered by Sublessee for any
               injury or damage (i) to any person or property whatsoever
               occurring in, on or about the Premises or any part thereof, the
               Building and/or other common areas, the use of which Sublessor
               may have in accordance with the Main Lease, if (and only if) such
               injury or damage shall be caused in whole or in part by the act,
               neglect, fault or omission of Sublessor, its agents, servants,
               employees, or invitees; (ii) arising from the conduct or
               management of any work done by the Sublessor in or about the
               Premises. The provisions of this paragraph shall survive the
               expiration or termination of this Sublease for a period of two
               (2) years.

          (d)  Paragraph 20.H, Landlord's Default, shall be modified by changing
                               ------------------
               the second to last sentence to read: In the event of any breach
               or default by Sublessor in any term or provision of this Sublease
               Agreement, Sublessee agrees to look solely to Sublessors interest
               in the Premises and the Building for satisfaction of any
               judgement obtained against Sublessor.

          (e)  Paragraph 25, Expansion/Right of First Refusal, of the Main Lease
                             --------------------------------
               shall not be incorporated herein;

          (f)  With respect to paragraph 28 of the Main Lease, Sublessee and
               Sublessor agree that the Net Profits Agreement is made by and
               between Lessor and

                                      2.
<PAGE>

               Sublessor and is not part of the relationship between Sublessor
               and Sublessee.

          Sublessee further agrees to indemnify and hold harmless Sublessor from
          any claim or liability arising under the Main Lease brought against
          Sublessor that are caused in whole or in part by the act, neglect,
          fault or omission of Sublessee, its agents, servants, employees, or
          invitees. Except as otherwise provided by this Sublease Agreement, the
          relationship between Sublessee and Sublessor shall be the same as that
          between Sublessor and Lessor under the Main Lease.

     5.   Sublessee agrees to pay Sublessor, as rent for the Sublease Space, the
          sum of Sixteen Thousand Two Hundred and 00/100 Dollars ($16,200.00),
                 ---------------------------------------         ------------
          per month, payable in advance on the first day of each calendar month
          during the term of this Sublease. In the event that the tenant
          improvements are not substantially complete, but for delays caused
          directly or indirectly by Sublessee, and ready for occupancy by
          January 31, 1997, then the rent during the first month of the lease
          term shall be appropriately abated and pro-rated.

     6.   In addition to the rent provided for above, Sublessee agrees to pay
          directly to Sublessor its Proportionate Share of the Tenant Costs (as
          defined in paragraph 2.C of the Main Lease) on the first day of each
          calendar month. The provisions of paragraph 2.C of the Main Lease that
          require the payments to be deposited in escrow with the Landlord shall
          not apply to this Sublease Agreement. Upon commencement of this
          Sublease Agreement Sublessee's Proportionate Share amounts to Two
                                                                        ---
          Thousand Five Hundred and Ninety Two Dollars ($2,592.00) which is
          -------------------------------------------- ----------
          equivalent to $0.12 per square foot per month and reflects the amount
          that Lessor is charging Sublessor at the effective date of this
          Sublease Agreement. During the term of this Sublease Agreement the
          amount of the Tenant Costs may change from the amount originally
          charged as the Landlord under the Main Lease makes changes to its
          reasonable projections of the actual amount of all Tenant Costs.
          Sublessor shall notify Sublessee in writing at the time of any change
          in Tenant Costs and Sublessee agrees to pay the amount then charged by
          Sublessor.

     7.   The following events shall be deemed to be events of default by
          Sublessee under this Sublease: any events of default by Sublessee,
          listed as events of default by Tenant set forth in the Main Lease, or
          any default in the provisions of this Sublease Agreement. Upon the
          occurrence of any such events of default, and in addition to any other
          available remedies provided by law or in equity, Sublessor shall have
          all remedies granted to Lessor in the Main Lease.

     8.   Upon execution of this Sublease, Sublessee shall deposit with
          Sublessor the sum of Sixteen Thousand Two Hundred and 00/100 Dollars
                               -----------------------------------------------
          ($16,200.00), as a security deposit to be held by Sublessor pursuant
          -----------
          to the provisions of the Main Lease.

     9.   Sublessor will pay an allowance to Sublessee of $12.00 per square foot
          which is equivalent to Two Hundred fifty-nine Thousand and Two Hundred
                                 -----------------------------------------------
          Dollars ($259,200) for the construction of Sublease's improvements to
          -------  --------
          the Sublease

                                      3.
<PAGE>

          Space. All improvements shall be constructed by Lessor's approved
          contractors in accordance with the plans and specifications approved
          by Sublessor and Sublessee. Sublessor shall pay for the completion of
          the improvements provided, however, Sublessee shall reimburse Landlord
          for any costs exceeding $259,200, such reimbursement to be paid upon
          substantial completion of the improvements.

     10.  Per paragraph 5.A of the Main Lease and paragraph 4 of the Second
          Amendment to Lease Agreement Between SL-6 PARTNERS, LTD., a Texas
          Limited Partnership, as Landlord, and Progressive System Technologies,
          Inc., as Tenant, Sublessor's share of parking totals two hundred
          eighty three (283) spaces. Sublessee shall have the right to ninety
          (90) un-reserved, non-exclusive parking spaces. In addition, Sublessee
          may at any time during the term of the Sublease Agreement, at its own
          cost and upon receipt of written permission from Sublessor, which
          permission shall not be unreasonably withheld, stripe the track court
          area on the north end of the Sublease Space for the purpose of
          parking.

     11.  At any time after the twenty-fourth month of the lease term, Sublessor
          shall have the ongoing right to terminate this Sublease Agreement by
          giving Sublessee six month's advance written notice of its intent to
          terminate.  In consideration therefore, Sublessor agrees to pay to
          Sublessee at the time Sublessee vacates the Sublease Space, an amount
          equal to Six Thousand Five Hundred Dollars ($6,500.00) per month of
          unexpired time remaining on the sublease term which Sublessee will
          forfeit as a result of early termination of the Sublease Agreement.

     12.  Time is of the essence of this Sublease, and each and all the terms
          hereof.

     13.  Any notice or other communication required or permitted to be given
          under this Sublease or under the Main Lease shall be in writing and
          shall be deemed to be delivered on the date it is hand delivered to
          the party to whom such notice is given, at the address set forth
          below, or if such notice is mailed, on the date on which it is
          deposited in the United States Mail, postage prepaid, certified or
          registered mail, return receipt requested, addressed to the party to
          whom such notice is directed, at the address set forth below:

     If to Sublessor:

          Ms. Sharon Foster
          Progressive System Technologies, Inc.
          11000 North Mopac Expressway, Suite 100
          Austin, Texas 78759

     If to Sublessee:

          Mr. Clark Covert
          Leasing Group, Inc.
          11000 North Mopac Expressway, Suite
          Austin, Texas 78759

                                      4.
<PAGE>

     14.  Sublessee shall have no right to assign or sublet any interest in this
          Sublease without first obtaining the written consent of the Lessor and
          Sublessor, which consent may or may not be granted by the Lessor or
          Sublessor in their sole opinion, judgment or discretion.

     15.  Sublessor shall have no liability to Sublessee for any wrongful action
          or default on the part of Lessor pursuant to the terms of the Main
          Lease, and Sublessee hereby agrees to look solely to Lessor in event
          of any such default, the liability and obligations of Sublessor being
          solely pursuant to the terms and conditions of this Sublease
          Agreement.

     16.  In the event any one or more of the provisions contained in this
          Sublease Agreement shall for any reason be held invalid, illegal, or
          unenforceable in any respect, such invalidity, illegality or
          unenforceability shall not affect any other provision hereof and this
          agreement shall be construed as if such invalid, illegal or
          unenforceable provisions had never been contained herein.

     17.  This agreement constitutes the sole and only agreement of the parties
          hereto and supersedes any prior understandings and written or oral
          agreements between the parties respecting the subject matter of this
          Sublease Agreement.

EXECUTED on the day and year first above written.

     SUBLESSOR:    Progressive System Technologies
     By:           /s/ Sharon Foster
                   --------------------
     Title:        CFO
                   --------------------

     SUBLESSEE:    Leasing Group, Inc.
     By:           /s/ Clark A. Covat
                   --------------------
     Title:        President
                   --------------------

                               CONSENT BY LESSOR
                               -----------------

     SL-6 PARTNERS, Ltd., Lessor under the Main Lease referred to in this
Sublease Agreement, hereby consents to the foregoing Sublease Agreement,
provided that this Sublease in no way modifies or amends the Main Lease, and
such consent shall not be construed in any way as a consent to any other
sublease of the Premises or assignment of the Lease.

                                          By:  TCCT Development, Inc.
                                               a Delaware corporation
     LESSOR: /s/ Andrew R. Pastor              Its General Partner
             --------------------
     By:     Andrew R. Pastor
             --------------------

     Title:  Vice President
             --------------------

                                      5.
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                                  Exhibit "A"

BUILDING:                Stonelake #6

LEGAL DESCRIPTION:       8,865 acres tract of land situated in the City of
                         Austin, Travis County, Texas being a portion of Lot 5
                         Block "A" Stonelake Section 3.

ADDRESS:                 North Mopac Expressway and Stonelake Boulevard, Austin,
                         Texas 78759


                                   [DIAGRAM]

                                      1.
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                                     The Prudential Insurance Company of America
                                                     The Prudential Realty Group
                                                One Prudential Plaza, Suite 1300
                                                          Chicago, IL 60601-6217
                                               312 861-4838   Fax:  312 861-4303

April 22, 1997

Progressive System Technologies, Inc.
11000 MoPac Expressway
Austin, TX

                                    RE:  Prudential Loan No.  6-101-132
                                    Mortgagor: SL-6 Partners, Ltd.  Property:
                                    Stonelake 6 Austin, Texas

To Whom It May Concern:

Please be advised that the above-named Mortgagor, your Landlord under that
certain Lease Agreement dated November 20, 1995, has assigned the Lease to The
Prudential Insurance Company of America as additional security for a loan on the
above-referenced property.  Such assignment has been made in the Assignment of
Leases and Rents, filed in the public records of Travis County, Texas, File
12801, Page 1854.

In the Assignment, your Landlord has agreed, among other things, that
Prudential's prior written consent shall be required for certain modifications
of the Lease.

We point out further that your Landlord is to continue to collect all rent under
the Lease unless and until a default under Prudential's loan occurs and you have
been notified that Prudential elects to collect the rent.

Very truly yours,

Patricia J. Haze
Legal Secretary
Real Estate Operations

/pjh

                                      1.