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                                                                     EXHIBIT 4.5


                                     WARRANT

NEITHER THE SECURITIES REPRESENTED HEREBY NOR THE SECURITIES ISSUABLE UPON THE
EXERCISE HEREOF HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS AND MAY NOT BE
OFFERED, SOLD, PLEDGED, ASSIGNED, OR OTHERWISE TRANSFERRED UNLESS (1) A
REGISTRATION STATEMENT WITH RESPECT THERETO IS EFFECTIVE UNDER THE SECURITIES
ACT AND ANY APPLICABLE STATE SECURITIES LAWS, OR (2) THE COMPANY RECEIVES AN
OPINION OF COUNSEL TO THE HOLDER OF THIS WARRANT OR SUCH SECURITIES, WHICH
COUNSEL AND OPINION ARE REASONABLY SATISFACTORY TO THE COMPANY, THAT THIS
WARRANT OR SUCH SECURITIES, AS APPLICABLE, MAY BE OFFERED, SOLD, PLEDGED,
ASSIGNED, OR OTHERWISE TRANSFERRED IN THE MANNER CONTEMPLATED WITHOUT AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR APPLICABLE STATE
SECURITIES LAWS.

        THE TRANSFER OF THIS WARRANT IS RESTRICTED AS DESCRIBED HEREIN.

                        INTERSCIENCE COMPUTER CORPORATION

                            Warrant for the Purchase
                                    of 12,500
                    Shares of Common Stock, Without Par Value

        THIS CERTIFIES that, for value received, Barry Lederman, (together with
all permitted assigns, the "Holder") is entitled to subscribe for, and purchase
from, INTERSCIENCE COMPUTER CORPORATION, a California corporation (the
"Company"), upon the terms and conditions set forth herein, at any time or from
time to time during the period commencing on September 17, 1999 (such date being
referenced to as the Initial Exercise Date), and terminating at 5:00 p.m., Los
Angeles local time, on the third anniversary of the Initial Exercise Date (the
"Exercise Period"). This Warrant is exercisable at an exercise price per share
equal to $0.50 per share; provided, however, that upon the occurrence of any of
the events specified in Section 5 hereof, the rights granted by this Warrant,
including the number of shares of Common Stock to be received upon such
exercise, shall be adjusted as therein specified.

        This Warrant is being issued pursuant to employment with Company as a
signing bonus.

        Each share of Common Stock issuable upon the exercise hereof shall be
hereinafter referred to as a "Warrant Share".

        SECTION 1     EXERCISE OF WARRANT

This Warrant may be exercised during the Exercise Period, either in whole or in
part, by the surrender of this Warrant (with the election at the end hereof duly
executed) to the Company at its office at 5236 Colodny Drive, Suite 100, Agoura
Hills, California 91301, or at such other place as is designated in writing by
the Company, together with a certified or bank cashier's


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check payable to the order of the Company in an amount equal to the product of
the Exercise Price and the number of Warrant Shares for which this Warrant is
being exercised.

        SECTION 2 RIGHTS UPON EXERCISE; DELIVERY OF SECURITIES

        Upon each exercise of the Holder's rights to purchase Warrant Shares,
the Holder shall be deemed to be the holder of record of the Warrant Shares,
notwithstanding that the transfer books of the Company shall then be closed or
certificates representing the Warrant Shares with respect to which this Warrant
was exercised shall not then have been actually delivered to the Holder. As soon
as practicable after each such exercise of this Warrant, the Company shall issue
and deliver to the Holder a certificate or certificates representing in the name
of the Holder or its designee. If this Warrant should be exercised in part only,
the Company shall, upon surrender of this Warrant for cancellation, execute and
deliver a Warrant evidencing the right of the Holder to purchase the balance of
the aggregate number of Warrant Shares purchasable hereunder as to which this
Warrant has not been exercised or assigned.

        SECTION 3 REGISTRATION OF TRANSFER AND EXCHANGE

        Any Warrants issued upon the transfer or exercise in part of this
Warrant shall be numbered and shall be registered in a warrant register (the
"Warrant Register") as they are issued. The Company shall be entitled to treat
the registered holder of any Warrant on the Warrant Register as the owner in
fact thereof for all purposes, and shall not be bound to recognize any equitable
or other claim to, or interest in, such Warrant on the part of any other person,
and shall not be liable for any registration or transfer of Warrants which are
registered or to be registered in the name of a fiduciary or the nominee of a
fiduciary unless made with the actual knowledge that a fiduciary or nominee is
committing a breach of trust in requesting such registration or transfer, or
with the knowledge of such facts that its participation therein amounts to bad
faith. This Warrant shall be transferable on the books of the Company only upon
delivery thereof duly endorsed by the Holder or by his duly authorized attorney
or representative, or accompanied by proper evidence of succession, assignment,
or authority to transfer. In all cases of transfer by an attorney, executor,
administrator, guardian, or other legal representative, duly authenticated
evidence of his, her, or its authority shall be produced. Upon any registration
of transfer, the Company shall deliver a new Warrant or Warrants to the person
entitled thereto. This Warrant may be exchanged, at the option of the Holder
thereof, for another Warrant, or other Warrants of different denominations, of
like tenor and representing in the aggregate the right to purchase a like number
of Warrant Shares (or portions thereof), upon surrender to the Company or its
duly authorized agent. Notwithstanding the foregoing, the Company shall have no
obligation to cause Warrants to be transferred on its books to any person if, in
the opinion of counsel to the Company, such transfer does not comply with the
provisions of the Securities Act and the rules and regulations thereunder.

        SECTION 4 RESERVATION OF SHARES

        The Company shall at all times reserve and keep available out of its
authorized and unissued Common Stock, solely for the purpose of providing for
the exercise of the Warrants, such number of shares of Common Stock as shall,
from time to time, be sufficient therefor. The Company represents that all
shares of Common Stock issuable upon exercise of this Warrant are


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duly authorized and, upon receipt by the Company of the full payment for such
Warrant Shares, will be validly issued, fully paid, and nonassessable, without
any personal liability attaching to the ownership thereof and will not be issued
in violation of any preemptive or similar rights of shareholders.

        SECTION 5 ANTIDILUTION

        (a)    In the event that the Company shall at any time after the Initial
               Exercise Date (i) declare a dividend on the outstanding Common
               Stock payable in shares of its capital stock, (ii) subdivide the
               outstanding Common Stock; (iii) combine the outstanding Common
               Stock into a smaller number of share; or (iv) issue any shares of
               its capital stock by reclassification of the Common Stock
               (including any such reclassification in connection with a
               consolidation or merger in which the Company is the continuing
               corporation), then, in each case, the Exercise Price per Warrant
               Share in effect at the time of the record date for the
               determination of shareholders entitled to receive such dividend
               or distribution or of the effective date of such subdivision,
               combination, or reclassification shall be adjusted so that it
               shall equal the price determined by multiplying such Exercise
               Price by a fraction, the numerator of which shall be the number
               of shares of Common Stock outstanding immediately prior to such
               action, and the denominator of which shall be the number of
               shares of Common Stock outstanding after giving effect to such
               action. Such adjustment shall be made successively whenever any
               event listed above shall occur and shall become effective at the
               close of business on such record date or at the close of business
               on the date immediately preceding such effective date as
               applicable.

        (b)    All calculations under this Section 5 shall be made to the
               nearest cent or to the nearest one-hundredth of a share, as the
               case may be.

        (c)    In any case in which this Section 5 shall require that an
               adjustment in the number of Warrant Shares be made effective as
               of a record date for a specified event, the Company may elect to
               defer, until the occurrence of such event, issuing to the Holder,
               if the Holder exercised this Warrant after such record date, the
               Warrant Shares, if any, issuable upon such exercise over and
               above the number of Warrant Shares issuable upon such exercise on
               the basis of the number of shares of Common Stock in effect prior
               to such adjustment; provided, however, that the Company shall
               deliver to the Holder a due bill or other appropriate instrument
               evidencing the Holder's right to receive such additional shares
               of Common Stock upon the occurrence of the event requiring such
               adjustment.

        (d)    Whenever there shall be an adjustment as provided in this Section
               5, the Company shall within 15 days thereafter cause written
               notice thereof to be sent by registered mail, postage prepaid, to
               the Holder, at its address as it shall appear in the Warrant
               Register, which notice shall be accompanied by an officer's
               certificate setting forth the number of Warrant Shares issuable
               and the Exercise Price thereof after such adjustment and setting
               forth the computation thereof, which officer's certificate shall
               be conclusive evidence of the correctness of any such adjustment
               absent manifest error.

        (e)    The Company shall not be required to issue fractions of shares of
               Common Stock or other capital stock of the Company upon the
               exercise of this Warrant. If any


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               faction of a share of Common Stock would be issuable on the
               exercise of this Warrant (or specified portions thereof), the
               Company shall purchase such fraction for an amount in cash equal
               to the same fraction of the average closing sale price (or
               average of the closing bid and asked prices, if closing sale
               price is not available) of Common Stock for the 10 trading days
               ending on and including the date of exercise of this Warrant.

        (f)    No adjustment in the Exercise Price per Warrant Share shall be
               required if such adjustment is less than $0.25; provided,
               however, that any adjustments which by reason of this Section 5
               are not required to be made shall be carried forward and taken
               into account in any subsequent adjustment.

        (g)    Whenever the Exercise Price payable upon exercise of this Warrant
               is adjusted pursuant to subsection (a) above, the number of
               Warrant Shares issuable upon exercise of this Warrant shall
               simultaneously be adjusted by multiplying the number of Warrant
               Shares theretofore issuable upon exercise of this Warrant by the
               Exercise Price in effect on the date hereof and dividing the
               product so obtained by the Exercise Price, as adjusted.

        SECTION 6 RECLASSIFICATION; REORGANIZATION; MERGER

        (a)    In case of any capital reorganization, other than in the cases
               referred to in Section 5(a) hereof, or the consolidation or
               merger of the Company with or into another corporation (other
               than a merger or consolidation in which the Company is the
               continuing corporation and which does not result in any
               reclassification of the outstanding shares of Common Stock or the
               conversion of such outstanding shares of Common Stock or the
               conversion of such outstanding shares of Common Stock into shares
               of other stock or other securities or property), or in the case
               of any sale, lease, or conveyance to another corporation of the
               property and assets of any nature of the Company as an entirety
               or substantially as an entirety (such actions being hereinafter
               collectively referred to as "Reorganizations"), there shall
               thereafter be deliverable upon exercise of this Warrant (in lieu
               of the number of Warrant Shares theretofore deliverable) the
               number of shares of stock or other securities or property to
               which a holder of the respective number of Warrant Shares which
               would otherwise have been deliverable upon the exercise of this
               Warrant would have been entitled upon such Reorganization if this
               Warrant had been exercised in full immediately prior to such
               Reorganization. In case of any Reorganization, appropriate
               adjustment, as determined in good faith by the Board of Directors
               of the Company, shall be made in the application of the
               provisions herein set forth with respect to the rights and
               interests of the Holder so that the provisions set forth herein
               shall thereafter be applicable, as nearly as possible, in
               relation to any shares or other property thereafter deliverable
               upon exercise of this Warrant. Any such adjustment shall be made
               by, and set forth in, a supplemental agreement between the
               Company, or any successor thereto, and the Holder, with respect
               to this Warrant, and shall for all purposes hereof conclusively
               be deemed to be an appropriate adjustment. The Company shall not
               effect any such Reorganization unless, upon or prior to the
               consummation thereof, the successor corporation, or if the
               Company shall be the surviving corporation in any such
               Reorganization and is not the issuer of the shares of stock or
               other


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               securities or property to be delivered to holders of shares of
               the Common Stock outstanding at the effective time thereof, then
               such issuer, shall assume by written instrument the obligation to
               deliver to the Holder such shares of stock, securities, cash, or
               other property as such Holder shall be entitled to purchase in
               accordance with the foregoing provision. In the event of sale,
               lease, or conveyance or other transfer of all or substantially
               all of the assets of the Company as part of a plan for
               liquidation of the Company, all rights to exercise this Warrant
               shall terminate 30 days after the Company gives written notice to
               the Holder that such sale or conveyance or other transfer has
               been consummated.

        (b)    In case of any reclassification or change of the shares of Common
               Stock issuable upon exercise of this Warrant (other than a change
               in par value or from a specified par value to not par value, or
               as a result of a subdivision or combination, but including any
               change in the shares into two or more classes or series of
               shares), or in case of any consolidation or merger of another
               corporation into the Company in which the Company is the
               continuing corporation and in which there is a reclassification
               or change (including a change to the right to receive cash or
               other property) of the shares of Common Stock (other than a
               change in par value, or from no par value to a specified par
               value, or as a result of a subdivision or combination, but
               including any change in the shares into two or more classes or
               series of shares), the Holder or holders of this Warrant shall
               have the right thereafter to receive upon exercise of this
               Warrant solely the property, cash, or any combination thereof
               receivable upon such reclassification, change, consolidation, or
               merger by a holder of the number of Warrant Shares for which this
               Warrant might have been exercised immediately prior to such
               reclassification, change, consolidation, or merger. Thereafter,
               appropriate provision shall be made for adjustments which shall
               be as nearly equivalent as practicable to the adjustments in
               Section 5.

        (c)    The above provisions of this Section 6 shall similarly apply to
               successive reclassifications and changes of shares of Common
               Stock and to successive consolidations, mergers, sales, leases,
               or conveyances.

        SECTION 7 NOTICE OF CERTAIN EVENTS

        In case at any time the Company shall propose:

        (a)    to pay any dividend or make any distribution on shares of Common
               Stock in shares of Common Stock or make any other distribution
               (other than regularly scheduled cash dividends which are not in a
               greater amount per share than the most recent such cash dividend)
               to all holders of Common Stock; or

        (b)    to issue any rights, warrants, or other securities to all holders
               of Common Stock entitling them to purchase any additional shares
               of Common Stock or any other rights, warrants, or other
               securities; or

        (c)    to effect any reclassification or change of outstanding shares of
               Common Stock or any consolidation, merger, sale, lease, or
               conveyance of property, as described in Section 6; or

        (d)    to effect any liquidation, dissolution, or winding-up of the
               Company; or


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        (e)    to take any other action which would cause an adjustment to the
               Exercise Price per Warrant Share;

        then, and in any one or more of such cases, the Company shall give
written notice thereof by registered mail, postage prepaid, to the Holder at the
Holder's address as it shall appear in the Warrant register, mailed at least 15
days prior to; (i) the date as of which the holders of record of shares of
Common Stock to be entitled to receive any such dividend, distribution, rights,
warrants, or other securities are to be determined; (ii) the date on which any
such reclassification, change of outstanding shares of Common Stock,
consolidation, merger, sale, lease, conveyance of property, liquidation,
dissolution, or winding-up is expected to become effective and the date as of
which it is expected that holders of record of shares of Common Stock shall be
entitled to exchange their shares for securities or other property, if any,
deliverable upon such reclassification, change of outstanding shares,
consolidation, merger, sale, lease, conveyance of property, liquidation,
dissolution, or winding-up; or (iii) the date of such action which would require
an adjustment to the Exercise Price per Warrant Share.

        SECTION 8 CHARGES AND TAXES

        The issuance of any shares or other securities upon the exercise of this
Warrant and the delivery of certificates or other instruments representing such
shares or other securities shall be made without charge to the Holder for any
tax or other charge in respect of such issuance. The Company shall not, however,
be required to pay any tax which may be payable in respect of any transfer
involved in the issue and delivery of any certificate in a name other than that
of the Holder and the Company shall not be required to issue or deliver any such
certificate unless and until the person or persons requesting the issue thereof
shall have paid to the Company the amount of such tax or shall have established
to the satisfaction of the Company that such tax has been paid.

        SECTION 9 PERIODIC REPORTS

        The Company agrees that following the Initial Exercise Date and until
all the Warrant Shares shall have been sold pursuant to Rule 144 under the
Securities Act, it shall keep current in filing all reports, statements, and
other materials required to be filed with the Commission to permit holders of
the Warrant Shares to sell such securities under Rule 144 under the Securities
Act.

        SECTION 10 LEGEND

        Until sold pursuant to the provisions of Rule 144 or otherwise
registered under the Securities Act, the Warrant Shares issued on exercise of
the Warrants shall be subject to a stop transfer order and the certificate or
certificates representing the Warrant Shares shall bear the following legend:

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS AND
MAY NOT BE OFFERED, SOLD, PLEDGED, ASSIGNED, OR OTHERWISE TRANSFERRED UNLESS (1)
A REGISTRATION STATEMENT WITH RESPECT THERETO IS EFFECTIVE UNDER


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THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS, OR (2) THE COMPANY
RECEIVES AN OPINION OF COUNSEL TO THE HOLDER OF THE SECURITIES, WHICH COUNSEL
AND OPINION ARE REASONABLY SATISFACTORY TO THE COMPANY, THAT SUCH SECURITIES MAY
BE OFFERED, SOLD, PLEDGED, ASSIGNED, OR OTHERWISE TRANSFERRED IN THE MANNER
CONTEMPLATED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES
ACT OR APPLICABLE STATE SECURITIES LAWS.

        SECTION 11 LOSS; THEFT; DESTRUCTION; MUTILATION

        Upon receipt of evidence satisfactory to the Company of the loss, theft,
destruction, or mutilation of any Warrant (and upon surrender of any Warrant if
mutilated), and upon receipt by the Company of reasonably satisfactory
indemnification, the Company shall execute and deliver to the Holder thereof a
new Warrant of like date, tenor, and denomination.

        SECTION 12 SHAREHOLDER RIGHTS

        The Holder of any Warrant shall not have, solely on account of such
status, any rights of a shareholder of the Company, either at law or in equity,
or to any notice of meetings of shareholders or of any other proceedings of the
Company, except as provided in this Warrant.

        SECTION 13 GOVERNING LAW

        This Warrant shall be construed in accordance with the laws of the State
of California applicable to contracts made and performed within such State,
without regard to principles of conflicts of law.

        IN WITNESS WHEREOF, the Company has executed this Warrant as of the date
first above written.

                                        INTERSCIENCE COMPUTER CORPORATION

                                        By:_____________________________________
                                           Walter Kornbluh
                                           President and Chief Executive Officer

[Seal]


__________________________________
Secretary



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                               FORM OF ASSIGNMENT

(To be executed by the registered holder if such holder desires to transfer the
attached Warrant.)

        FOR VALUE RECEIVED, ____________________ hereby sells, assigns, and
transfers unto ______________________ a Warrant to purchase _____________ shares
of Common Stock, without par value, of Interscience Computer Corporation, a
California corporation (the "Company"), and does hereby irrevocably constitute
and appoint _________________ attorney to transfer such Warrant on the books of
the Company, with full power of substitution.

Dated:________________________



                                      Signature:________________________________


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                                     NOTICE

        The signature on the foregoing Assignment must correspond to the name as
written upon the face of this Warrant in every particular, without alteration or
enlargement or any change whatsoever.


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                              ELECTION TO EXERCISE

To:     Interscience Computer Corporation
        5236 Colodny Drive
        Agoura Hills, California 91301



        The undersigned hereby exercises his, her, or its rights to purchase
shares of Common Stock, without par value ("the Common Stock"), of Interscience
Computer Corporation, a California corporation (the "Company"), covered by the
within Warrant and tenders payment herewith in the amount of $_____________ in
accordance with the terms thereof, and requests that certificates for the
securities constituting such shares of Common Stock be issued in the name of,
and delivered to:


     -----------------------------------------------------------------------
     (Print Name, Address, and Social Security or Tax Identification Number)

and, if such number of shares of Common Stock shall not constitute all such
shares of Common Stock covered by the within Warrant, that a new Warrant for the
balance of the shares of Common Stock covered by the within Warrant shall be
registered in the name of, and delivered to, the undersigned at the address
stated below.



Dated:___________________________            Name:______________________________
                                                  (Print)



Address:

_________________________________

_________________________________                 ______________________________
                                                  (Signature)


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