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                                                                     Exhibit 4.2

                               AMENDMENT NO. 1 TO
                                WARRANT AGREEMENT


         Amendment No. 1 (the "Amendment") to a certain Warrant Agreement, dated
as of July 26, 1994, between Innovative Tech Systems, Inc., an Illinois
corporation (the "Company"), and Continental Stock Transfer & Trust Company, a
New York corporation, as Warrant Agent (the "Warrant Agent").

         WHEREAS, the Company and the Warrant Agent made, executed and delivered
a certain Warrant Agreement, dated July 26, 1994 (the "Original Warrant
Agreement"); and

         WHEREAS, the Company and the Warrant Agent have agreed to make certain
amendments to the terms and provisions of the Original Warrant Agreement upon
the terms and conditions set forth herein.

         NOW, THEREFORE, in consideration of the mutual promises herein
contained, and each intending to be legally bound hereby, the parties hereto
hereby agree as follows:

                  1. Except as expressly defined herein, all capitalized terms
used herein shall have the meanings ascribed to them in the Original Warrant
Agreement. This Amendment is intended to amend the Original Warrant Agreement
and the Original Warrant Agreement shall be so amended from and as of the date
hereof.

                  2. The Original Warrant Agreement shall be amended so that all
references to "Agreement" contained therein shall mean the Original Warrant
Agreement, as amended herein, and as further amended, supplemented or modified
from time to time.

                  3. The Original Warrant Agreement is hereby further amended so
that the term "Warrants" shall mean (a) the 1,324,500 redeemable common stock
purchase warrants heretofore issued by the Company and outstanding on the date
hereof (after giving effect to the one-for-three split of the redeemable common
stock purchase warrants effectuated by the Company on September 18, 1995 and the
one-for-eight reverse split of all outstanding redeemable common stock purchase
warrants effectuated by the Company on the date hereof), and (b) the 6,750
additional redeemable common stock purchase warrants issuable by the Company
upon the exercise of the Underwriter's Warrants outstanding on the date hereof
(after giving effect to the one-for-three split of the Underwriter's Warrants
effectuated by the Company on September 18, 1995 and the one-for-eight reverse
split of all outstanding Underwriter's Warrants effectuated by the Company on
August 21, 1997). Each Warrant entitles the holder thereof to purchase one share
of the Company's Common Stock, par value $.0185 per share.

                  3. The Original Warrant Agreement is hereby further amended so
that Section 1(f) thereof reads in its entirety as follows:


                     "Purchase Price" shall mean, subject to modification and
                     adjustment as provided in Section 8, $0.08 per share of
                     Common Stock and further subject to the Company's right, in
                     its sole 



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                     discretion, to decrease the Purchase Price for a period of
                     not less than thirty days on not less than thirty days'
                     prior written notice to the Registered Holders and the
                     Underwriter."

                  4. As soon as practicable following the date hereof, the
Company and Warrant Agent shall cause all outstanding Warrant Certificates to be
returned to the Warrant Agent in exchange for new warrant certificates (the
"Replacement Warrant Certificates") which incorporate the revisions to the
Original Warrant Agreement effected by this Amendment, but which otherwise are
substantially in the same form as the original Warrant Certificates. Following
the issuance of the Replacement Warrant Certificates, all references to the
"Warrant Certificates" contained in the original Warrant Agreement shall mean
the Replacement Warrant Certificates.

                  5. Except as modified by the terms hereof, all terms,
provisions and conditions of the Original Warrant Agreement, and all documents
duly executed and delivered in connection therewith, are in full force and
effect, and are hereby incorporated by reference as if set forth herein. If
there is any conflict or discrepancy between the provisions of this Amendment
and any provision of the Original Warrant Agreement, the terms and provisions of
this Amendment shall control and prevail.

                  6. This Amendment (a) shall be construed and enforced in
accordance with the laws of the State of New York, without giving effect to
conflicts of laws; (b) shall inure to the benefit of, and be binding upon, the
parties hereto and their respective successors and assigns; (c) may be executed
in two or more counterparts, each of which shall be deemed an original, but all
of which together shall constitute one and the same instrument; and (d) may only
be amended or modified pursuant to a writing signed by the parties hereto.

         IN WITNESS WHEREOF, the undersigned have caused this Amendment to be
executed and delivered by their respective officers thereunto duly authorized as
of the 30th day of September, 1997.

                                         INNOVATIVE TECH SYSTEMS, INC.

                                         By:
                                            --------------------------------
                                            John M. Thompson, President

                                         CONTINENTAL STOCK TRANSFER
                                         & TRUST COMPANY

                                         By:
                                            --------------------------------
                                         Name:
                                              ------------------------------
                                         Title:
                                               -----------------------------


                                       2

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                       CONSENT OF A.S. GOLDMEN & CO., INC.


         The undersigned hereby irrevocably consents to the terms and provisions
of the foregoing Amendment to the Warrant Agreement dated as of July 26, 1994
between Innovative Tech Systems, Inc. and Continental Stock Transfer & Trust
Company. The undersigned further ratifies and confirms that all references to
the "Redeemable Warrant Agreement" contained in the Underwriter's Warrant
Agreement, dated as of July 26, 1994, between the undersigned and Innovative
Tech Systems, Inc. (the "Underwriter's Warrant Agreement") shall, from and after
the date hereof, mean the Redeemable Warrant Agreement, as amended by the
preceding Amendment. The undersigned further irrevocably consents to an
amendment to the Underwriter's Warrant Agreement to effectuate (a) a
one-for-eight reverse split of all of the outstanding Underwriter's Warrants
(from 54,000 to 6,750 Underwriter's Warrants), and (b) a one-for-twenty-nine and
one-eighth reduction in the present exercise price of the outstanding
Underwriter's Warrants (from $0.125 to $0.01 per Underwriter's Warrant).

         IN WITNESS WHEREOF, the undersigned has caused this instrument to be
duly executed, intending to be legally bound hereby, as of the 30th day of
September, 1997.


                                              A.S. GOLDMEN & CO., INC.

                                              By:
                                                 -----------------------------

                                              Name:
                                                   ---------------------------
                                              Title:
                                                    --------------------------