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                                                                  EXHIBIT 4.15.1

                         AMENDMENT AGREEMENT WITH LAURUS

         This Amendment Agreement (this "AGREEMENT"), dated as of August 15,
2005, is entered into by and among EPIXTAR CORP. ("EPXR"), the other entities
set forth on the signature pages hereto (EPXR and such other entities, each a
"Company" and collectively the "COMPANIES") and LAURUS MASTER FUND, LTD.
("LAURUS").

         Reference is made to (a) the Securities Purchase Agreement, dated as of
July 15, 2005 (as the same may be amended, supplemented, restated or modified
from time to time, the "PURCHASE AGREEMENT"), by and between EPXR and Laurus,
(b) the Secured Convertible Term Note in the original principal amount of
$6,200,000, dated as of July 15, 2005 (the "JULY 2005 TERM NOTE"), made by EPXR
in favor of Laurus and (c) all documents, instruments and agreements executed in
connection with the Purchase Agreement and the July 2005 Term Note (together
with the Purchase Agreement and the July 2005 Term Note, collectively, and as
may be amended, supplemented, restated or modified from time to time, the "JULY
2005 DOCUMENTS").

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

         The defined term "Maximum Amount" set forth in the introductory
paragraph of the July 2005 Term Note is hereby amended by deleting the words
"Six Million Two Hundred Thousand Dollars ($6,200,000)" and replacing the same
with the words "Fourteen Million Two Hundred Thousand Dollars ($14,200,000)";

         All references in the July 2005 Documents to the July 2005 Term Note
shall mean and refer to the July 2005 Term Note as amended pursuant to the terms
hereof and as the same may be further amended, supplemented, restated or
modified from time to time.

         EXPR hereby notifies Laurus that EXPR has appointed Mr. Martin Miller
to the position of chief executive officer of EPXR. Laurus hereby acknowledges
that such appointment is reasonably acceptable to Laurus.

         The Companies hereby notify Laurus that the Companies have hired and
retained Realization Services, Inc. as one of the Companies' financial advisors
(the "Financial Advisor"). Laurus hereby acknowledges that such retention is
reasonably acceptable to Laurus.

         Each Company acknowledges that it shall fully cooperate with the
Financial Advisor and hereby authorizes the Financial Advisor to conduct all
such examinations with respect to such Company's financial condition, business,
assets, liabilities and prospects, including without limitation a complete and
thorough examination of each Companies' books and records, in each case as the
Financial Advisor may from time to time deem appropriate. All fees and expenses
of the Financial Advisor shall be the sole responsibility of the Companies and
in no event shall Laurus have any liability or responsibility for the payment of
such fees or expenses nor shall Laurus have any obligation or liability to any
Company or any other person or entity by reason of any acts or omissions of the
Financial Advisor.

         Each Company hereby acknowledges that all proceeds of Collateral (as
hereafter defined) received by Laurus shall be applied by Laurus to the
obligations and liabilities of the Companies to Laurus in such order as Laurus
shall elect. For purposes hereof, the term "Collateral" means those assets of
any Company in which Laurus has been granted a security interest.

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         Except as expressly provided herein, all of the representations,
warranties, terms, covenants and conditions of the July 2005 Documents shall
remain unamended and shall continue to be and shall remain in full force and
effect in accordance with their respective terms. Except as expressly provided
herein, this Agreement shall not act as a wavier or excuse of performance of any
obligations contained in any of the July 2005 Documents.

         The Companies hereby represent and warrant to Laurus that as of the
date hereof all representations, warranties and covenants made by the Companies
under the July 2005 Documents are true, correct and complete and the Companies'
covenant requirements set forth in such documents have been met.

         The Companies hereby acknowledge that if any Company breaches any of
the provisions of this Agreement applicable to it, such breach will constitute
an "Event of Default" pursuant to the July 2005 Term Note, the other July 2005
Documents and all other documents, instruments and agreements by and between
Laurus and any one or more of the Companies.

         The Companies acknowledge that (i) certain post-closing items required
to be delivered to Laurus in accordance with the terms of the post-closing
letter dated July 15, 2005 remain outstanding, (ii) Laurus has not waived
delivery of such post-closing items and (iii) Laurus reserves all of its rights
and remedies in connection therewith.

         This Agreement shall be binding upon the parties hereto and their
respective successors and permitted assigns and shall inure to the benefit of
and be enforceable by each of the parties hereto and its successors and
permitted assigns. THIS AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE
WITH AND GOVERNED BY THE LAW OF THE STATE OF NEW YORK. This Agreement may be
executed in any number of counterparts, each of which shall be an original, but
all of which shall constitute one agreement.

                                     * * * *

IN WITNESS WHEREOF, each Company and Laurus have caused this Agreement to be
effective and signed in its name effective as of the date set forth above.

                                  EPIXTAR CORP.


                                  By:________________________________
                                     Name:
                                     Title:



                                  NOL GROUP, INC.


                                  By:________________________________
                                     Name:
                                     Title:



                                  NATIONAL ONLINE SERVICES, INC.


                                  By:________________________________
                                     Name:
                                     Title:



                                  LIBERTY ONLINE SERVICES, INC.


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                                  By:________________________________
                                     Name:
                                     Title:



                                  AMERIPAGES, INC.


                                  By:________________________________
                                     Name:
                                     Title:



                  [SIGNATURE LINES CONTINUED ON FOLLOWING PAGE]


                                  B2B ADVANTAGE, INC.




                                  By:________________________________
                                     Name:
                                     Title:



                                  EPIXTAR INTERNATIONAL CONTACT CENTER GROUP,
                                    INC.


                                  By:________________________________
                                     Name:
                                     Title:



                                  VOXX CORPORATION


                                  By:________________________________
                                     Name:
                                     Title:



                                  EPIXTAR MARKETING CORP.


                                  By:________________________________
                                     Name:
                                     Title:



                                  LAURUS MASTER FUND, LTD.


                                  By:________________________________
                                     Name:
                                     Title:

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