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                                                                    EXHIBIT 10.8

                                    GUARANTY

       This Guaranty, dated as of November 2, 2001, is made by Kris Shah (the
"Guarantor") for the benefit of Wells Fargo Business Credit, Inc., a Minnesota
corporation ("WFBCI").

       WFBCI and Pulsar Data Systems, Incorporated, a Delaware corporation, a
Delaware corporation (the "Customer"), are parties to an Account Purchase
Agreement dated November 2nd, 2001 (the "Agreement") pursuant to which WFBCI
shall purchase accounts receivable from the Customer and may make financial
accommodations to the Customer.

       As a condition to entering into the Agreement and extending such
accommodations to the Customer, WFBCI has required the execution and delivery of
this Guaranty.

       ACCORDINGLY, the Guarantor, in consideration of the premises and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, hereby agrees as follows:

              1. Definitions. All terms defined in the Agreement that are not
otherwise defined herein shall have the meanings given them in the Agreement.

              2. Indebtedness Guaranteed. The Guarantor hereby absolutely and
unconditionally guarantees to WFBCI the full and prompt payment when due,
whether at maturity or earlier by reason of acceleration or otherwise, of each
and every sum now or hereafter owing to WFBCI by the Customer, including but not
limited to, debts, liabilities and obligations arising out of purchases of
property, financial accommodations, or other transactions with the Customer or
for the Customer's account or out of any other transaction or event, owed to
WFBCI, in each case whether now existing or hereafter arising, whether arising
directly in a transaction or event involving WFBCI or acquired by WFBCI from
another by purchase or assignment or as collateral security, whether owed by the
Customer as drawer, maker, endorser, accommodation party, guarantor, principal,
surety or as a member of any partnership, syndicate, association or group or in
any other capacity, whether absolute or contingent, direct or indirect, primary
or secondary, sole, joint, several or joint and several, secured or unsecured,
due or not due, contractual, tortious or statutory, liquidated or unliquidated,
arising by agreement or imposed by law or otherwise (all of said sums being
hereinafter called the "Indebtedness").

              3. Unconditional Guaranty. No act or thing need occur to establish
the liability of the Guarantor hereunder, and no act or thing, except full
payment and discharge of all of the Indebtedness, shall in any way exonerate the
Guarantor hereunder or modify, reduce, limit or release the Guarantor's
liability hereunder. This is an absolute, unconditional and continuing guaranty
of payment of the Indebtedness and shall continue to be in force and be binding
upon the Guarantor, whether or not all of the Indebtedness is paid in full,
until this Guaranty is revoked prospectively as to future transactions, by
written notice actually received by WFBCI, and such revocation shall not be
effective as to the amount of Indebtedness existing or committed for at the time
of actual receipt of such notice by WFBCI, or as to any renewals, extensions,
refinancings or refundings thereof. The death or incompetence of the Guarantor
shall not revoke this Guaranty, except upon actual receipt of written notice
thereof by WFBCI and only prospectively, as to future transactions, as herein
set forth.

              4. Death or Insolvency of Guarantor. If the Guarantor shall die or
shall be or become insolvent (however defined), then WFBCI shall have the right
to declare immediately due and payable, and the Guarantor will forthwith pay to
WFBCI, the full amount of all of the Indebtedness whether due and payable or
unmatured. If the

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Guarantor voluntarily commences or there is commenced involuntarily against the
Guarantor a case under the United States Bankruptcy Code, the full amount of all
of the Indebtedness, whether due and payable or unmatured, shall be immediately
due and payable without demand or notice thereof.

              5. Subrogation, etc. The Guarantor hereby waives all rights that
the Guarantor may now have or hereafter acquire, whether by subrogation,
contribution, reimbursement, recourse, exoneration, contract or otherwise, to
recover from the Customer or from any property of the Customer any sums paid
under this Guaranty. The Guarantor will not exercise or enforce any right of
contribution to recover any such sums from any person who is a co-obligor with
the Customer or a guarantor or surety of the Indebtedness or from any property
of any such person until all of the Indebtedness shall have been fully paid and
discharged.

              6. Enforcement Expenses. The Guarantor will pay or reimburse WFBCI
for all costs, expenses and attorneys' fees paid or incurred by WFBCI in
endeavoring to collect and enforce the Indebtedness and in enforcing this
Guaranty.

              7. WFBCI's Rights. WFBCI shall not be obligated by reason of its
acceptance of this Guaranty to engage in any transactions with or for the
Customer. Whether or not any existing relationship between the Guarantor and the
Customer has been changed or ended and whether or not this Guaranty has been
revoked, WFBCI may enter into transactions resulting in the creation or
continuance of the Indebtedness and may otherwise agree, consent to or suffer
the creation or continuance of any of the Indebtedness, without any consent or
approval by the Guarantor and without any prior or subsequent notice to the
Guarantor. The Guarantor's liability shall not be affected or impaired by any of
the following acts or things (which WFBCI is expressly authorized to do, omit or
suffer from time to time, both before and after revocation of this Guaranty,
without consent or approval by or notice to the Guarantor): (i) any acceptance
of collateral security, guarantors, accommodation parties or sureties for any or
all of the Indebtedness; (ii) one or more extensions or renewals of the
Indebtedness (whether or not for longer than the original period) or any
modification of the interest rates, discount rates, fees, expenses, maturities,
if any, or other contractual terms applicable to any of the Indebtedness or any
amendment or modification of any of the terms or provisions of any agreement
under which the Indebtedness or any part thereof arose; (iii) any waiver or
indulgence granted to the Customer, any delay or lack of diligence in the
enforcement of the Indebtedness or any failure to institute proceedings, file a
claim, give any required notices or otherwise protect any of the Indebtedness;
(iv) any full or partial release of, compromise or settlement with, or agreement
not to sue, the Customer or any guarantor or other person liable in respect of
any of the Indebtedness; (v) any release, surrender, cancellation or other
discharge of any evidence of the Indebtedness or the acceptance of any
instrument in renewal or substitution therefor; (vi) any failure to obtain
collateral security (including rights of setoff) for the Indebtedness, or to see
to the proper or sufficient creation and perfection thereof, or to establish the
priority thereof, or to preserve, protect, insure, care for, exercise or enforce
any collateral security; or any modification, alteration, substitution,
exchange, surrender, cancellation, termination, release or other change,
impairment, limitation, loss or discharge of any collateral security; (vii) any
collection, sale, lease or disposition of, or any other foreclosure or
enforcement of or realization on, any collateral security; (viii) any
assignment, pledge or other transfer of any of the Indebtedness or any evidence
thereof; (ix) any manner, order or method of application of any payments or
credits upon the Indebtedness; and (x) any election by WFBCI under Section
1111(b) of the United States Bankruptcy Code. The Guarantor waives any and all
defenses and discharges available to a surety, guarantor or accommodation
co-obligor.

              8. Waivers by Guarantor. The Guarantor waives any and all
defenses, claims, setoffs and discharges of the Customer, or any other obligor,
pertaining to the Indebtedness, except the defense of discharge by payment in
full. Without limiting the generality of the foregoing, the Guarantor will not
assert, plead or enforce against WFBCI any defense of waiver, release, discharge
or disallowance in bankruptcy, statute of limitations, res judicata, statute of
frauds, anti-deficiency statute, fraud, incapacity, minority, usury, illegality
or unenforceability which may be available to the Customer or any other person
liable in respect of any of the Indebtedness, or any setoff available against
WFBCI to the Customer or any other such person, whether or not on account of a
related transaction. The Guarantor expressly agrees that the Guarantor shall be
and remain liable for any deficiency remaining after foreclosure of any mortgage
or security


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interest securing the Indebtedness, whether or not the liability of the Customer
or any other obligor for such deficiency is discharged pursuant to statute or
judicial decision. The liability of the Guarantor shall not be affected or
impaired by any voluntary or involuntary liquidation, dissolution, sale or other
disposition of all or substantially all the assets, marshalling of assets and
liabilities, receivership, insolvency, bankruptcy, assignment for the benefit of
creditors, reorganization, arrangement, composition or readjustment of, or other
similar event or proceeding affecting, the Customer or any of its assets. The
Guarantor will not assert, plead or enforce against WFBCI any claim, defense or
setoff available to the Guarantor against the Customer. The Guarantor waives
presentment, demand for payment, notice of dishonor or nonpayment and protest of
any instrument evidencing the Indebtedness. WFBCI shall not be required first to
resort for payment of the Indebtedness to the Customer or other persons, or
their properties, or first to enforce, realize upon or exhaust any collateral
security for the Indebtedness, before enforcing this Guaranty.

              9. If Payments Set Aside, etc. If any payment applied by WFBCI to
the Indebtedness is thereafter set aside, recovered, rescinded or required to be
returned for any reason (including, without limitation, the bankruptcy,
insolvency or reorganization of the Customer or any other obligor), the
Indebtedness to which such payment was applied shall for the purpose of this
Guaranty be deemed to have continued in existence, notwithstanding such
application, and this Guaranty shall be enforceable as to such Indebtedness as
fully as if such application had never been made.

              10. Additional Obligation of Guarantor. The Guarantor's liability
under this Guaranty is in addition to and shall be cumulative with all other
liabilities of the Guarantor to WFBCI as guarantor, surety, endorser,
accommodation co-obligor or otherwise of any of the Indebtedness or obligation
of the Customer, without any limitation as to amount, unless the instrument or
agreement evidencing or creating such other liability specifically provides to
the contrary.

              11. Financial Information. The Guarantor will provide to WFBCI
annually a current personal financial statement listing all assets, liabilities
and net worth of the Guarantor and copies of his federal and state tax returns
and all schedules thereto. The statement will be signed and dated and will be
forwarded with the tax returns to WFBCI not later than April 30th of each year.
The Guarantor acknowledges and agrees that WFBCI may at any time and from time
to time without notice to the Guarantor, investigate the Guarantor's background,
personal and credit history and perform other due diligence concerning the
Guarantor and his creditworthiness.

              12. No Duties Owed by WFBCI. The Guarantor acknowledges and agrees
that WFBCI (i) has not made any representations or warranties with respect to,
(ii) does not assume any responsibility to the Guarantor for, and (iii) has no
duty to provide information to the Guarantor regarding, the enforceability of
any of the Indebtedness or the financial condition of the Customer or any
guarantor. The Guarantor has independently determined the creditworthiness of
the Customer and the enforceability of the Indebtedness and until the
Indebtedness is paid in full will independently and without reliance on WFBCI
continue to make such determinations.

              13. Acknowledgement. The Guarantor acknowledges that it or s/he
has read this Guaranty in its entirety, has consulted such legal, tax or other
advisors as it or s/he deems appropriate and understands and agrees to each of
the provisions of this Guaranty and further acknowledges that it or s/he has
entered into this Guaranty voluntarily.

              14. Miscellaneous. This Guaranty shall be effective upon delivery
to WFBCI, without further act, condition or acceptance by WFBCI, shall be
binding upon the Guarantor and the heirs, representatives, successors and
assigns of the Guarantor and shall inure to the benefit of WFBCI and its
participants, successors and assigns. Any invalidity or unenforceability of any
provision or application of this Guaranty shall not affect other lawful
provisions and application thereof, and to this end the provisions of this
Guaranty are declared to be severable. This Guaranty may not be waived,
modified, amended, terminated, released or otherwise changed except by a writing
signed by the Guarantor and WFBCI. This Guaranty shall be governed by and
construed in accordance with the substantive laws (other than conflict laws) of
the State of Colorado. The Guarantor hereby (i) consents to the personal
jurisdiction of the state and federal courts located in the State of Colorado in
connection with any controversy related to this Guaranty; (ii) waives


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any argument that venue in any such forum is not convenient, (iii) agrees that
any litigation initiated by WFBCI or the Guarantor in connection with this
Guaranty shall be venued in either the District Court of Denver County, Denver
Colorado, or the United States District Court, District of Colorado; and (iv)
agrees that a final judgment in any such suit, action or proceeding shall be
conclusive and may be enforced in other jurisdictions by suit on the judgment or
in any other manner provided by law.

              15. Termination. This Guaranty may not be terminated by the
Guarantor until all of the Customer's obligations to WFBCI have been paid in
full or otherwise satisfied and the Guarantor provides WFBCI with written notice
of the termination of this Guaranty. By execution hereof, the Guarantor
knowingly accepts the full range of risk encompassed within a contract of
"continuing guaranty" which risk includes, without limitation, the possibility
that the Customer will incur additional obligations for which the Guarantor may
be liable hereunder after the Customer's financial condition or ability to pay
its lawful debts when they are due has deteriorated, and the Guarantor
understands that the amount of the obligations may be increased or decreased and
the ratios of obligations to Collateral may be changed adversely to the
Guarantor at the sole discretion of WFBCI.

              16. Waiver of Jury Trial. THE UNDERSIGNED HEREBY IRREVOCABLY
WAIVES ALL RIGHTS TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM
ARISING OUT OF, BASED ON OR PERTAINING TO THIS GUARANTY.

              IN WITNESS WHEREOF, this Guaranty has been duly executed by the
Guarantor as of the date first written above.

                                          Signature /s/ KRIS SHAH
                                                    ----------------------------
                                          Kris Shah
                                          40 Mission Bay Drive
                                          Corona Del Mar  CA  92625
STATE OF CALIFORNIA   )                   ###-##-####
                      )
COUNTY OF ORANGE      )
               The foregoing instrument was acknowledged before me the 1st day
of November, 2001, by Kris Shah.

                                          /s/ NANCY R. McKENNA
                                          --------------------------------------
                                              Notary Public Nancy R. McKenna

[SEAL]


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