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                                                                    Exhibit 10.4

                                                          American National Bank
                                                          and Trust Company of
                                                          Chicago

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                                   GUARANTY
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     WHEREAS, QUANTUM LEAP COMMUNICATIONS, INC., a corporation organized under
the laws of Delaware; with principal offices located at 22 West Hubbard Street,
Chicago, Illinois 60610 (hereafter referred to as the "Borrower"), desires or
may desire at some time and/or from time to time to obtain financial
accommodation from AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO
(hereafter referred to as the "Bank"); and

     WHEREAS, the undersigned guarantor is either a corporation or company,
desiring to induce the Bank, at its option, at any time, or from time to time,
to extend financial accommodation to the Borrower, and represents to the Bank
that it is organized under the laws of the State of Delaware and that the
Borrower (a) is engaged in business as a corporate affiliate or subsidiary of
the undersigned, and/or (b) is engaged in selling, marketing, using or otherwise
dealing in goods supplied to it by the undersigned, or supplies to the
undersigned goods sold, marketed, used or otherwise disposed of by the
undersigned, and/or (c) the undersigned expects to derive advantage by assisting
the Borrower in procuring financial assistance from the Bank; or the undersigned
is a(n) individual(s) or partnership desiring to induce the Bank at its option,
at any time, or from time to time, to extend financial accommodation to the
Borrower (said undersigned corporation, company, individual(s) or partnership,
as the case may be, is severally hereinafter referred to as the "undersigned").

1.   NOW THEREFORE, FOR VALUE RECEIVED, and in consideration of advances, credit
or other financial accommodation heretofore, now or hereafter at any time
extended to the Borrower by the Bank, the undersigned (jointly and severally if
there is more than one guarantor) hereby unconditionally guarantee(s) the full
and prompt payment to the Bank at maturity, whether by acceleration or
otherwise, and at all times thereafter of any and all "Indebtedness".
"Indebtedness" shall mean obligations and liabilities of every kind and nature
of the Borrower to the Bank (including all indebtedness, obligations and
liabilities of partnerships, created or arising while the Borrower  is or was a
member thereof), including principal and interest, however evidenced, whether
now existing or hereafter created or arising, directly or indirectly, primary or
secondary, absolute or contingent, due or to become due, or joint or several,
and however owned, held or acquired, whether through discount, overdraft,
returned checks, purchase, direct loan or as collateral, or otherwise.

     The undersigned further unconditionally guarantees the prompt, full and
faithful performance and discharge by the Borrower of all of the terms,
conditions, agreements, representations and warranties on the part of the
Borrower contained in any agreement, or in any modification or addenda thereto
or substitution thereof in connection with any advance, credit or financial
accommodation afforded by the Bank to the Borrower.

     The undersigned further agree(s) to pay all expenses, including, without
limitation, legal fees and court costs paid or incurred by the Bank in
endeavoring to collect the Indebtedness, or any part thereof, in enforcing this
guaranty, arising out of any post-judgment proceedings, or in defending any suit
based on any act or omission of the Bank with respect to the Indebtedness,
collateral, or this guaranty or in connection with any Recovery Claim
hereinbelow defined (hereafter, collectively referred to as "Expenses").

2.   The term "Guaranteed Debt," as used herein, shall be deemed to mean an
amount equal to all of the Indebtedness plus Expenses.

3.   In case of the death, incompetence, dissolution, liquidation or insolvency
(however evidenced) of the Borrower, a principal of the Borrower, or any
guarantor of the Indebtedness or in case any bankruptcy, reorganization, debt
arrangement or other proceeding under any bankruptcy or insolvency law, or any
dissolution, liquidation or receivership proceeding, is instituted by or against
the Borrower, or any of the undersigned or any other guarantor of the
Indebtedness or the inability of the Borrower or any of the undersigned to pay
debts as they mature, or in case of the assignment by the Borrower or any of the
undersigned for the benefit of creditors, then upon the occurrence of any
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such event, all Guaranteed Debt then existing shall at the option of the Bank,
without notice to anyone, immediately become due or accrued and be payable from
the undersigned (or any thereof if more than one guarantor).

4.   All payments received from whatever source shall be applied toward the
payment of the Indebtedness in such order of application as the Bank may in its
sole discretion, from time to time elect, and this determination shall be
conclusive upon the undersigned.

5.   This guaranty shall in all respects be a continuing, absolute and
unconditional guaranty, and shall remain in full force and effect with respect
to each guarantor until written notice shall have been actually received by the
Bank by first class  or certified mail, of its discontinuance as to such
guarantor, or of the death or dissolution of such guarantor, and also until all
Guaranteed Debt created or existing before receipt of such notice shall have
been fully paid. In case of any such discontinuance, or death or dissolution of
any guarantor or guarantors and notice thereof to the Bank, this guaranty shall
nevertheless continue and remain in force against the other guarantor or
guarantors until discontinued as to such other guarantor or guarantors as herein
provided. No compromise, settlement, release or discharge of, or indulgence with
respect to, or failure, negligence or omission to enforce or exercise any right
against, any one or more guarantors or the fact that at any time or from time to
time, all the Guaranteed Debt may have been paid in full, shall release or
discharge the undersigned. In the event of the death of the undersigned, this
guaranty shall continue as to all Indebtedness theretofore incurred by the
Borrower even though said Indebtedness is renewed or the time of maturity of
Indebtedness  is extended without the consent of the executors or administrators
of the undersigned. This guaranty shall be valid, irrespective of the validity,
regularity or enforceability of any instrument, writing or agreement relating to
any Indebtedness,  whether or not such Indebtedness is due or to become due
before or after any bankruptcy or insolvency proceeding involving the Borrower.

6.   The liability hereunder shall in no way be affected or impaired by any of
the following, any or all of which may be done or omitted by the Bank in its
sole discretion without notice to anyone and irrespective of whether the
Guaranteed Debt shall be increased or decreased thereby (and said Bank is hereby
expressly authorized in its sole discretion to make from time to time, without
notice to anyone): any sale, pledge, surrender, compromise, settlement,
exchange, release, renewal, extension, modification, election with respect to
any collateral under Section 1111 or any other provision or section of the
Bankruptcy Code now existing or hereinafter amended; or other disposition of or
with respect to any of said Guaranteed Debt or any security or collateral
therefor, whether or not such disposition is commercially reasonable or
accomplished in a commercially reasonable manner; and such liability shall in no
way be affected or impaired by any acceptance by the Bank of any security for,
or other guarantors or obligors of, any of the Guaranteed Debt, or by any
forbearance or indulgence by the Bank in the collection of, or any failure,
negligence or omission on its part to realize upon any thereof, or to enforce
any claims against any person or persons primarily or secondarily liable
thereon, or upon any collateral or security therefor or to enforce any lien upon
or right of appropriation of any moneys, credits or property of the Borrower in
the possession and control of the Bank, or by an application of any payments or
credits on the Guaranteed Debt. Any act or omission of any kind or at any time
upon the part of the Bank with respect to any matter whatsoever shall not in any
manner affect or impair this guaranty nor the liability thereunder. The
undersigned hereby consents to all acts and omissions of the Bank set forth
herein.

7.   In order to hold the undersigned liable hereunder and to enforce this
guaranty, there shall be no obligation on the part of the Bank at any time to
resort for payment to the Borrower, or to any other guarantor, or any person,
firm or corporation liable for the Guaranteed Debt, or to any collateral,
security, property, liens or other rights or remedies of the Bank in respect to
the Guaranteed Debt or any part thereof, all of which is hereby expressly waived
by the undersigned.

8.   All diligence in collection, and any presentment for payment, demand,
protest and/or notice, as to any and everyone, of protest, dishonor, default or
nonpayment, and notice of the creation and existence of any and all of the
Guaranteed Debt, and of any security therefor, and of the acceptance of this
guaranty, or extensions of credit or indulgences hereunder or of any other
matters or things whatsoever relating hereto are expressly waived.

9.   The granting of additional credit from time to time by the Bank to the
Borrower in excess of the amount to which the right of recovery under this
guaranty is limited or in excess of the amount extended to the Borrower at the
time this guaranty is executed by the undersigned, without notice to the
undersigned, is hereby expressly authorized and shall in no way affect or impair
this guaranty.

10.  To secure payment of the Guaranteed Debt, the undersigned grants to Bank a
security interest in all property of the undersigned, including any and all
cash, negotiable instruments, documents of title, chattel paper, securities,
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certificates of deposit, deposit accounts, other cash equivalents and other
assets delivered currently herewith or now or at any time hereafter in transit
to, or in the possession or control of the Bank, or any agent or bailee of Bank,
and all proceeds of all such property. The undersigned agrees that the Bank
shall have the rights and remedies of a secured party under the Uniform
Commercial Code of Illinois with respect to all of the aforesaid property,
including, without limitation thereof, the right to sell or otherwise dispose of
any or all of such property. THE UNDERSIGNED WAIVES EVERY DEFENSE, COUNTERCLAIM
OR SETOFF WHICH THE UNDERSIGNED MAY NOW HAVE OR HEREAFTER MAY HAVE TO ANY ACTION
BY THE BANK IN ENFORCING THIS GUARANTY, INCLUDING, WITHOUT LIMITATION, EVERY
DEFENSE, COUNTERCLAIM OR SETOFF WHICH THE UNDERSIGNED MAY NOW HAVE, OR HEREAFTER
MAY HAVE, AGAINST THE BORROWER OR ANY OTHER PARTY LIABLE TO THE BANK IN ANY
MANNER. As further security, any and all debts and liabilities now or hereafter
arising and owing to any of the undersigned by the Borrower, or any other party
liable to the Bank are hereby subordinated to the Bank's claims and are hereby
assigned to the Bank. The undersigned ratifies and confirms whatever the Bank
may do pursuant to the terms hereof and with respect to any collateral for the
Guaranteed Debt, and agrees that the Bank shall not be liable for any error of
judgment or mistakes of fact or law. The Bank may, without notice to anyone,
apply or set off any balances, credits, deposits, accounts, moneys or other
indebtedness at any time credited by or due from the Bank to any of the
undersigned against the Guaranteed Debt. Any notification of intended
disposition of any property required by law shall be deemed reasonable and
properly given if given at least five (5) calendar days before such disposition.

11.  Should a claim ("Recovery Claim") be made upon the Bank at any time for
recovery of any amount received by the Bank in payment of the Guaranteed Debt
(whether received from the Borrower, the undersigned pursuant hereto, or
otherwise) and should the Bank repay all or part of said amount by reason of (i)
any judgment, decree, or order of any court or administrative body having
jurisdiction over the Bank or any of its property; or (ii) any settlement or
compromise of any such Recovery Claim effected by the Bank with the claimant
(including the Borrower), the undersigned shall remain jointly and severally
liable to the Bank for the amount so repaid to the same extent as if such amount
had never originally been received by the Bank, notwithstanding any termination
hereof or the return of this document to any of the undersigned or the
cancellation of any note, this guaranty or other instrument evidencing any of
the Indebtedness.

12.  In the event the Bank shall sell, assign or transfer the Indebtedness or
Guaranteed Debt, or any part thereof, or grant participations therein, each and
every immediate or remote successive assignee, transferee, holder of or
participant therein, of all or any part of the Indebtedness or Guaranteed Debt
shall have the right to enforce this guaranty by suit or otherwise for the
benefit of such assignee, transferee, holder or participant, as fully as if such
assigned transferee, holder or participant were herein by name specifically
given such rights, powers and benefits; but the Bank shall have an unimpaired,
prior and superior right to enforce this guaranty for its benefit as to so much
of the Indebtedness or Guaranteed Debt as it has not been sold, assigned or
transferred.

13.  No release or discharge of any one or more of the undersigned (if there is
more than one guarantor), or of any other person, whether primarily or
secondarily liable for and obligated with respect to the Guaranteed Debt, or the
institution of bankruptcy, receivership, insolvency, reorganization, dissolution
or liquidation proceedings by or against any such guarantor or person, or the
entry of any restraining or other order in any such proceeding, shall release or
discharge the undersigned or any other guarantor of the Guaranteed Debt, or any
other person, firm or corporation liable to the Bank for the Guaranteed Debt,
unless and until all of the Guaranteed Debt shall have been fully paid and this
guaranty stamped "Canceled" and returned to the undersigned.

14.  No delay on the part of the Bank in the exercise of any right or remedy
shall operate as a waiver thereof, and no single or partial exercise by the Bank
of any right or remedy shall preclude any other or further exercise thereof, or
the exercise of any other right or remedy. No action of the Bank permitted
hereunder shall in any way affect or impair the rights of the Bank and the
obligation of the undersigned under this guaranty.

15.  To the extent that the Borrower or any of the undersigned is a corporation,
limited liability company or partnership, all references herein to the Borrower
and to the undersigned, respectively, shall be deemed to include any successor
or successors, whether immediate or remote, to such corporation, limited
liability company or partnership.

16.  This guaranty has been delivered at Chicago, Illinois, and shall be
construed according to the laws of the State of Illinois, in which state it
shall be performed by the undersigned. All actions arising directly or
indirectly as a result or in consequence of this guaranty shall, in the sole and
absolute discretion of the Bank, be instituted and litigated only in courts
having situs in the City of Chicago, Illinois, and the undersigned hereby
consents to the
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jurisdiction of any State or Federal Court located and having its situs in said
city and waives any right to transfer or change the venue of any litigation.

17.  Wherever possible, each provision of this guaranty shall be interpreted in
such manner as to be effective and valid under applicable law, but if any
provision of this guaranty shall be prohibited by or invalid under such law,
such provision shall be ineffective to the extent of such prohibition or
invalidity, without invalidating the remainder of such provision or the
remaining provisions of this guaranty.

18.  It is agreed that the undersigned's liability hereunder is several and is
independent of any other guaranties at any time in effect with respect to all or
any part of the Indebtedness and that the undersigned's liability hereunder may
be enforced regardless of the existence of any such other guaranties.

19.  This guaranty, and each and every part hereof, shall be binding upon the
undersigned (jointly and severally if there is more than one guarantor) and upon
the heirs, legal representatives, successors and assigns of the undersigned, and
shall inure to the benefit of the Bank, its successors and assigns.

20.  If the undersigned guarantor is a corporation, then and in such event, the
undersigned guarantor expressly represents and warrants unto the Bank that the
execution and delivery of this guaranty has been duly authorized by resolutions
heretofore duly adopted by its Board of Directors in accordance with law and its
by-laws, that said resolutions have not been amended nor rescinded, are in full
force and effect, that the officers of the undersigned executing and delivering
this guaranty, for and on behalf of the undersigned, are duly authorized and
empowered so to act. The Bank in accepting this guaranty is expressly relying
upon the aforesaid representations and warranties.

21.  This guaranty constitutes the entire agreement between the parties relating
to the subject matter hereof and is the final and complete expression of their
intent. No prior or contemporaneous negotiations, promises, agreements,
covenants or representations of any kind or nature, whether made orally or in
writing, have been made by the parties, or any of them, in negotiations leading
to this guaranty or relating to the subject matter hereof, which are not
expressly contained herein, or which have not become merged and finally
integrated into this guaranty; it being the intention of the parties hereto that
in the event of any subsequent litigation, controversy or dispute concerning the
terms and provisions of this guaranty, no party shall be permitted to offer to
introduce oral or extrinsic evidence concerning the terms and conditions hereof
that are not included or referred to herein and not reflected in writing. This
guaranty can only be changed, modified, waived or discharged if consented to in
a writing duly signed and delivered on behalf of the Bank. No conditions exist
to the legal effectiveness of this guaranty.

22.  THE UNDERSIGNED HEREBY IRREVOCABLY WAIVES ANY RIGHT TO TRIAL BY JURY IN ANY
ACTION OR PROCEEDING (i) TO ENFORCE OR DEFEND ANY RIGHTS UNDER OR IN CONNECTION
WITH THIS GUARANTY OR AN AMENDMENT, INSTRUMENT, DOCUMENT OR AGREEMENT DELIVERED
IN CONNECTION HEREWITH, OR (ii) ARISING FROM ANY DISPUTE OR CONTROVERSY IN
CONNECTION WITH OR RELATED TO THIS GUARANTY, AND AGREES THAT ANY SUCH ACTION OR
PROCEEDING SHALL BE TRIED BEFORE A COURT AND NOT BEFORE A JURY.

SIGNED AND SEALED by the undersigned effective this 29/th/ day of June, 1999.


                                           Guarantor

Address:  22 West Hubbard Street           Leapnet, Inc., a Delaware corporation
          Chicago, Illinois 60610
                                       By: /s/ Robert C. Bramlette
                                           -------------------------------------
                                           Chief Legal Officer
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                                           Printed Name
                                           Tax I.D. Number: