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                                                                   EXHIBIT 10.10
 
                ADDENDUM TO LICENSE AND CROSS-LICENSE AGREEMENT
 
     This Addendum, dated February 28, 1997, modifies the License and Cross
License Agreement ("License Agreement") dated May 1, 1992 between The Titan
Corporation ("Titan"), a Delaware corporation, and Cryptologics International,
Inc., a Delaware corporation now known as Wave Systems Corp. ("Wave"), as
amended by an Amendment dated August 27, 1993, a waiver letter dated February 7,
1994, a Consent dated October 12, 1994, a letter amendment dated March 20, 1996
and a waiver letter dated January 3, 1997. The License Agreement is the Exhibit
A to a Joint Technology Development Agreement between the same parties and with
the same date. The parties hereby agree as follows:
 
          1.  Definitions.  In addition to the definitions in this Addendum, the
     definitions in the License Agreement shall apply to this Addendum.
 
          2.  Modifications of License Grant.  Section 2.1 of the License
     Agreement is hereby amended to delete the word "exclusive."
 
          3.  Modification of Rights.  Section 2.1 of the License Agreement is
     hereby amended to add the following at the end of that Section:
 
             The grant of rights to CII (Wave) for the consumer microcomputer
        market portion of the Licensed Market shall be exclusive except for
        Titan (and its subsidiaries and affiliates), which may not grant further
        licenses or sublicenses. The grant of rights for all other portions of
        the Licensed Market shall be non-exclusive.
 
          4.  Waiver of Defaults.  Titan hereby waives any and all defaults by
     Wave under the License Agreement prior to the date of this Addendum,
     including without limitation any failures by Wave to comply with the
     performance or payment provisions of Section 13.2 of the License Agreement.
 
          5.  Modification of Requirements: Termination.  In consideration of
     Wave agreeing to reduce the scope of its exclusive rights under the License
     Agreement, Section 13.2 of the License Agreement is deleted in its entirety
     and replaced with the following:
 
             13.2 This Agreement shall automatically expire when all of the
        patents listed in Exhibit A to the License Agreement have expired. Upon
        such expiration, the provisions of Section 13.3 shall not apply.
 
          6.  Miscellaneous.  In the event of any conflict between the terms of
     this Addendum and the terms of the License Agreement, as previously
     amended, the terms of this Addendum shall prevail. Except as modified by
     the Addendum, the License Agreement, as previously amended, shall continue
     in full force and effect. This Addendum may be executed in multiple
     counterparts, each of which shall be deemed an original.
 
     IN WITNESS WHEREOF, the parties have caused this Addendum to be executed.
 
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<S>                                              <C>
THE TITAN CORPORATION                            WAVE SYSTEMS CORP.
 
/s/ GENE W. RAY                                  /s/ STEVEN SPRAGUE
Authorized Officer                               Authorized Officer
 
GENE W. RAY                                      STEVEN SPRAGUE          PRESIDENT
Print Name and Title                             Print Name and Title
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