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                                                                   EXHIBIT 99.15


                         AMENDMENT AND WAIVER AGREEMENT

THIS AMENDMENT AND WAIVER AGREEMENT (this "Agreement"), dated as of May 5, 2004,
is entered into by and among MERCATOR MOMENTUM FUND, L.P., a California limited
partnership ("MMF"), MERCATOR MOMENTUM FUND III, L.P., a California limited
partnership ("MMFIII"), MERCATOR FOCUS FUND, L.P., a California limited
partnership ("MFF" and together with MMF and MMFIII, the "Lenders" and each of
them, a "Lender"), MERCATOR ADVISORY GROUP, LLC, as Agent for Lenders ("Agent"),
and PRESIDION SOLUTIONS, INC., a Florida corporation ("Company"), and PRESIDION
CORPORATION, formerly known as MediaBus Networks, Inc., a Florida corporation
("Parent" and together with Company, the "Borrowers" and each, a "Borrower"), as
with reference to the following facts:

                                    RECITALS


A.       Borrowers have issued, on a joint and several basis, that certain 6.5%
         Secured Convertible Debenture due February 12, 2004 in the original
         principal amount of $1,560,000 in favor of MFF (as amended from time to
         time, the "MFF Debenture").

B.       Borrowers have issued, on a joint and several basis, that certain 6.5%
         Secured Convertible Debenture due February 12, 2004 in the original
         principal amount of $240,000 in favor of MMF (as amended from time to
         time, the "MMF Debenture").

C.       Borrowers have issued, on a joint and several basis, that certain 6.5%
         Secured Convertible Debenture due February 12, 2004 in the original
         principal amount of $200,000 in favor of MMFIII (as amended from time
         to time, the "MMFIII Debenture" and together with the MFF Debenture and
         the MMF Debenture, the "Debentures").

D.       Borrowers have defaulted (such Defaults, the "Existing Defaults"):

              (1) under Section 3(a)(ii) of each of the Debentures, by reason of
                  the fact that Parent has failed to file the Underlying Share
                  Registration Statement with the Commission within sixty days
                  of the Original Issue Date;

              (2) under Section 3(a)(viii) of each of the Debentures, by reason
                  of the fact that the Underlying Share Registration Statement
                  has not been declared effective by the Commission on or prior
                  to the one hundred and fiftieth day of the Original Issue
                  Date; and,

              (3) under Section 3(a)(i) of each of the Debentures, by reason of
                  the fact the principal has not been paid as of the Maturity
                  Date set forth therein.

E.       Borrowers have requested that Agent and Lenders:


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         (1)      forbear from exercising their available default rights and
         remedies under the Debentures and applicable law in response to the
         Existing Defaults;

         (2)      waive the Existing Defaults; and

         (3)      amend each of the Debentures as set forth below.

F.       Agent and Lenders are willing to provide Borrowers with the foregoing
         accommodations on the terms and conditions hereinafter set forth.

                                    AGREEMENT

NOW, THEREFORE, the parties hereby agree as follows:

1.       Defined Terms. All initially capitalized terms used in this Agreement
         (including, without limitation, in the Recitals hereto) shall have the
         respective meanings specified in the Debentures.

2.       Amendment to Debentures. Each of the Debentures is hereby amended as
         follows:


         (a)      by amending and restating Section 3(a)(ii) of such Debenture,
                  in full as follows:

                  "(ii) the Parent shall fail to file the Underlying Shares
                  Registration Statement with the Commission on or prior to July
                  31, 2004,"

         (b)      by amending and restating Section 3(a)(viii) of such
                  Debenture, in full as follows:

                  "(viii) an Underlying Shares Registration Statement (as
                  defined in Section 5) shall not have been declared effective
                  by the Commission (as defined in Section 5) on or prior to
                  July 31, 2004. The Company and the Parent shall each use their
                  best efforts and all available resources to have the
                  Underlying Shares Registration Statement declared effective by
                  the Commission on or prior to July 31, 2004,"

         (c)      by amending and restating all references to the Maturity Date
                  to read as follows:

                  "July 31, 2004"

3.       Waiver. Agent and Lenders hereby waive, on a one-time basis, the
         Existing Defaults provided that such waiver shall not constitute a
         waiver of:

         (a)      any future breach of Sections 3(a)(ii) or 3(a)(viii) of any of
                  the Debentures; or

         (b)      any other term, condition, covenant, representation or
                  warranty contained in any Debenture or any future breach
                  thereof.


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4.       Condition Precedent. The effectiveness of this Agreement shall be
         subject to the prior satisfaction of each of the following conditions:

         (a)      Agreement. Agent shall have received this Agreement, duly
                  executed by each of the Lenders and the Borrowers.

         (b)      Registration Rights Agreement. The Parent shall have executed
                  and delivered to Lenders a Registration Rights Agreement, in
                  the form attached hereto as Exhibit "A".

         (c)      Consent and Amendment Agreement of Guarantors. Each of the
                  Company, Craig A. Vanderburg, John W. Burcham II and James E.
                  Baiers (the "Guarantors") shall have executed the Consent and
                  Amendment Agreement of Guarantors in the form attached hereto
                  as Exhibit "B".


         (d)      Waiver and Amendment Fee. Borrowers shall have paid the Waiver
                  and Amendment Fee to Agent in immediately available funds.

5.       Waiver and Amendment Fee. In consideration of Agent's and Lenders'
         agreement to enter into this Agreement and provide Borrowers with the
         accommodations provided hereunder Borrowers shall, concurrent with the
         execution of this Agreement, pay to the Agent on behalf of the Lenders
         a monthly fee, payable on the first of each calendar month commencing
         January 1, 2004 and continuing thru July 1, 2004 in the amount of
         $8,572.00 per month (the "Waiver and Amendment Fee") which shall be
         fully-earned when paid and nonrefundable. The amount of the Waiver and
         Amendment Fee accrued as of the date of this Agreement, $42,860.00,
         shall be due and payable immediately.

6.       Redemption of Debentures. Borrowers shall immediately tender to Lenders
         a redemption payment with respect to the Debentures in an amount (a
         "Redemption Amount") equal to 50% of the net cash proceeds (after
         deduction of all reasonable transactional expenses) received by the
         Borrowers from each offering of their debt or equity securities, or
         from any loan transaction, following the date of this Agreement;
         provided that the Redemption Amount shall not exceed the redemption
         price of the then outstanding Debentures. The redemption price shall be
         115% of the principal amount redeemed plus accrued interest. Subject to
         the Lenders' acceptance of any such tender, if the Redemption Amount
         equals or exceeds the redemption price of the then outstanding
         Debentures, then all of the Debentures shall be redeemed, while if the
         Redemption Amount is less than the redemption price for the then
         outstanding Debentures, then the Debentures shall be partially
         redeemed. All redemption payments shall be allocated ratably among the
         Debentures. The Borrowers' failure to immediately tender such a
         redemption payment with respect to the Debentures in accordance with
         the terms hereof shall constitute an Event of Default under each of the
         Debentures. Notwithstanding the foregoing, the Lenders may (in their
         sole and absolute discretion) refuse to accept any such tendered
         redemption payment. If the Lenders so refuse, the Debentures shall not
         be redeemed and will remain outstanding.


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7.       Reimbursement of Expenses. Borrowers shall be obligated, jointly and
         severally, to reimburse Agent and Lenders for any and all legal fees
         (including the reasonable legal fees of Agent and Lenders' outside
         counsel) and other expenses which are incurred by them in connection
         with the approval, documentation, negotiation and implementation of
         this Agreement or in connection with the Existing Defaults within 5
         days of receiving demand therefor. The Borrowers' failure to timely
         reimburse such fees shall constitute an Event of Default under each of
         the Debentures.

8.       Release. In consideration of the execution and delivery of this
         Agreement, and the forbearances and waivers requested of the Lenders,
         each Borrower hereby releases, remises and forever discharges Agent and
         Lenders, and each of them, and their respective officers, directors,
         employees, agents, affiliates and attorneys, without conditions
         precedent to effectiveness, from all actions and causes of action
         heretofore arising out of or related to the Debentures or any document,
         instrument or agreement executed in connection therewith or relating
         thereto, or the relationship of any Borrower to Agent or any Lender, in
         each case whether known or unknown to any Borrower as of the date
         hereof. Each Borrower acknowledges that it has been advised by legal
         counsel, to the extent that it has seen fit, and is familiar with and
         waives the provision of California Civil Code Section 1542, which
         provides as follows:

                  "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE
                  CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE
                  TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE
                  MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR."

9.       No Other Amendments; Reaffirmation of Debentures; No Defenses. Except
         as expressly amended hereby, the Debentures shall remain unaltered and
         in full force and effect. Each Borrower hereby reaffirms the Debentures
         and its obligations to Lenders thereunder. Each Borrower represents and
         warrants to Agent and Lenders that there are no outstanding Events of
         Default under any Debenture other than the Existing Defaults. Borrower
         acknowledges that Agent and Lenders have fully complied with their
         obligations under the Debentures and that Borrowers have no defenses to
         the validity, enforceability or binding effect of any of the
         Debentures.

10.      Counterparts. This Agreement may be executed in multiple counterparts,
         each of which shall constitute an original, and all of which, taken
         together, shall constitute but one and the same agreement.

11.      Recitals. Each Borrower acknowledges and agrees that the Recitals set
         forth above are true and correct and are incorporated by reference
         herein.

12.      Governing Law. This Agreement shall be governed by and construed in
         accordance with the laws of the State of California, without giving
         effect to conflicts of laws thereof.

13.      Facsimile Transmission. Facsimile transmission of a signed original of
         this Amendment or retransmission of any signed facsimile transmission
         will be deemed the

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         same as delivery of an original. At the request of any other party
         hereto, each of the undersigned will confirm facsimile transmission by
         signing a duplicate original document.

IN WITNESS WHEREOF, the parties have executed this Amendment by their respective
duly authorized officers as of the date first above written.

                                     AGENT:

                                     MERCATOR ADVISORY GROUP, LLC, as
                                     Agent for Lenders

                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________


                                     LENDERS:

                                     MERCATOR MOMENTUM FUND, L.P.

                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________


                                     MERCATOR MOMENTUM FUND III, L.P.

                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________


                                     MERCATOR FOCUS FUND, L.P.

                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________


                    (Signatures continued on following page)


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                                     BORROWERS:

                                     PRESIDION CORPORATION,
                                     a Florida corporation

                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________

                                     PRESIDION SOLUTIONS, INC.,
                                     a Florida corporation


                                     By:____________________________
                                     Name:__________________________
                                     Title:___________________________





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                                   EXHIBIT "A"

                          REGISTRATION RIGHTS AGREEMENT




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                                   EXHIBIT "B"

                  CONSENT AND AMENDMENT AGREEMENT OF GUARANTORS

This Consent and Amendment Agreement of Guarantors (this "Agreement") is made as
of May 5, 2004, by each of the undersigned (collectively, the "Guarantors" and
each, a "Guarantor"), in favor of MERCATOR MOMENTUM FUND, L.P., a California
limited partnership ("MMF"), MERCATOR MOMENTUM FUND III, L.P., a California
limited partnership ("MMFIII"), MERCATOR FOCUS FUND, L.P., a California limited
partnership ("MFF" and together with MMF and MMFIII, the "Lenders" and each of
them, a "Lender") and MERCATOR ADVISORY GROUP, LLC, as Agent for Lenders
("Agent").

                                    RECITALS

A.       Each Guarantor has executed a Payment Guaranty, dated as of February
         11, 2003 (each, a "Guaranty" and collectively, the "Guaranties"),
         pursuant to which such Guarantor unconditionally guaranteed to Agent,
         for the benefit of the Lenders, the full payment of the Loan. All
         initially capitalized terms used in this Agreement but not defined
         shall have the respective meanings set forth in the Guaranties.

B.       Concurrently herewith Borrowers are entering into an Amendment and
         Waiver Agreement dated the date hereof with Agent and Lenders (the
         "Amendment"), pursuant to which Agent and Lenders have agreed to waive
         the Existing Defaults (as defined in the Amendment) and to amend
         certain provisions of the Loan Documents, all as more fully set forth
         in the Amendment.

C.       Guarantors are entering into this Agreement to induce the Lenders to
         enter into the Amendment.

                                    AGREEMENT

NOW, THEREFORE, Guarantors, Agent and Lenders agree as follows:

1.       Amendments to Guaranties.  Each Guaranty is hereby amended as follows:

         (a)      Mercator Momentum Fund III, L.P., a California limited
                  partnership shall be a party to and a "Lender" under each
                  Guaranty. For greater certainty, the term "Lenders" shall
                  mean, collectively, Mercator Momentum Fund, L.P., a California
                  limited partnership, Mercator Momentum Fund III, L.P., a
                  California limited partnership, and Mercator Focus Fund, L.P.,
                  a California limited partnership and the term "Lender" shall
                  mean any of them.

         (b)      Recital "A" to each Guaranty is hereby amended and restated in
                  full as follows:

                  "A. Guarantor is executing this Guaranty to induce Lenders to
                  make three separate loans (defined, together in Section 2 as
                  the "Loan") to Presidion Corporation, formerly known as
                  MediaBus Networks, Inc., a Florida corporation, and Presidion
                  Solutions, Inc., a Florida corporation (each a

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                  "Borrower" and together, "Borrowers"), in the aggregate
                  principal amount of Two Million Dollars ($2,000,000.00)."

2.       Reaffirmation of Guaranties.  Each Guarantor hereby:

         (a)      ratifies and reaffirms all provisions, terms, covenants, and
                  waivers set forth in its respective Guaranty, as amended
                  hereby as of the date hereof; and

         (b)      agrees that its respective Guaranty, as amended hereby,
                  constitutes a valid, binding obligation of such Guarantor,
                  enforceable according to its terms, for which there is no
                  offset, counterclaim, dispute, or defense of any kind or
                  nature.

3.       Consent to Amendment. Each Guarantor hereby acknowledges it has
         received copies of, and consents to, the Amendment and the documents,
         instruments and agreements executed in connection therewith and agrees
         that its respective Guaranty shall remain in full force and effect,
         without waiver or modification (except as amended hereby),
         notwithstanding the execution and performance of the Amendment and the
         documents, instruments and agreements executed in connection therewith.
         Each Guarantor hereby agrees that the execution of this Agreement is
         not necessary for the continued validity and enforceability of its
         respective Guaranty, but it is executed to induce the Lenders to enter
         into the Amendment.

4.       Facsimile Transmission. Facsimile transmission of a signed original of
         this Agreement or retransmission of any signed facsimile transmission
         will be deemed the same as delivery of an original. At the request of
         the Lenders, or any of them, each of the undersigned will confirm
         facsimile transmission by signing a duplicate original document.


                                     PRESIDION SOLUTIONS, INC.,
                                     a Florida corporation


                                     By:____________________________
                                     Name:__________________________
                                     Title:_________________________



                                     _______________________________
                                     CRAIG A. VANDERBURG


                    (Signatures continued on following page)




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                                     ----------------------------
                                     JOHN W. BURCHAM II




                                     ----------------------------
                                     JAMES E. BAIERS


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