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Exhibit 10.30.4

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Agreement"), dated as of December 19,
2002, between CRYPTO.COM, INC., a Delaware corporation (the "Assignor"), and
SECURITY TECHNOLOGY, INC., a Delaware corporation ("Assignee").

                              W I T N E S S E T H :

WHEREAS, Assignee and Assignor wish to enter into this Agreement in order to
consummate the assignment to Assignee of the Transferred Property owned by
Assignor (as described on, and as limited by the contents of, Schedule A
attached hereto) pursuant to the terms and conditions of that certain Exchange
Agreement, dated December 9, 2002, by and among Assignee, Assignor and certain
other parties, as same has been amended heretofore (the "Exchange Agreement").
Capitalized terms used but not defined herein shall have the meanings ascribed
such terms in the Exchange Agreement.

NOW, THEREFORE, in consideration of the assignment of the Transferred Property
and the mutual benefits to be derived by the parties hereto pursuant to the
Exchange Agreement, Assignee and Assignor hereby agree as follows:

1. (a)   Assignor does hereby sell, transfer, assign, and deliver to
         Assignee all of the right, title, and interest of Assignor in, to, and
         under the Transferred Property, and all improvements in support of or
         arising out of the Transferred Property, including but not limited to
         modifications, inventions, supplemental and ancillary patents or trade
         secrets, intellectual or industrial property, technology, know-how,
         works of authorship and goodwill created by Assignor subsequent to the
         Closing Date.

   (b)   Assignee does hereby accept all the right, title, and interest of
         Assignor in, to, and under all of the Transferred Property.

   (c)   Subject to the terms and conditions of the Exchange Agreement, Assignee
         and Assignor will use their best efforts to take, or cause to be taken,
         all actions and to do, or cause to be done, all things necessary or
         desirable under applicable laws and regulations to consummate the
         transactions, contemplated by the Exchange Agreement. Assignor and
         Assignee agree to execute and deliver, or cause to be executed and
         delivered such other documents, certificates, agreements, and other
         writings and to take such other actions as may be necessary or
         desirable in order to consummate or implement expeditiously the
         transactions contemplated by the Exchange Agreement and to vest in
         Assignee good and marketable title to the Transferred Property.

2. This Agreement shall be governed by and construed in accordance with the law
of the State of New York, without regard to the conflicts of law rules of such
state.

3. This Agreement may be executed in one or more counterparts, and by facsimile,
each of which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed as of the day and year first above written.



                                         CRYPTO.COM, INC.

                                         By:    /s/ Don V. Hahnfeldt
                                                --------------------------------
                                         Name:  Don V. Hahnfeldt
                                                --------------------------------
                                         Title: President
                                                --------------------------------


                                         SECURITY TECHNOLOGY INC.

                                         By:    /s/ Ken Ducey, Jr.
                                                --------------------------------
                                         Name:  Ken Ducey, Jr.
                                                --------------------------------
                                         Title: Executive Vice President
                                                --------------------------------

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                Schedule A to Assignment and Assumption Agreement

                              Transferred Property

Assignor hereby transfers to Assignee all right, title in interest that Assignor
currently owns and possesses in certain proprietary software and related
intellectual property concerning cryptology (including, without limitation, all
source code, object code and all materials and documents) which Crypto acquired
in February, 2000 and has subsequently developed (the "Crypto Technology") for
development in all commercial markets, including but not limited to, government,
commercial, and private enterprise computer and communications security
software.

The Crypto Technology is protected as a trade secret. Assignor has no federally
registered copyright to the Crypto Technology, but asserts common law
copyrights. The trademark "Crypto.com" is federally registered (Serial Number
76308457) and is transferred to Assignee together with the Crypto Technology.

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