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                                                                    EXHIBIT 10.4

THIRD AMENDMENT TO AGREEMENT NO. 095-1 FOR PROVISION OF INTERNATIONAL SATELLITE
SERVICES VIA THE MEXICAN SATELLITE SYSTEM EXECUTED BETWEEN SATELITES MEXICANOS,
S.A. DE C.V. ("SATMEX"), REPRESENTED BY ING. LAURO ANDRES GONZALEZ MORENO,
GENERAL DIRECTOR AND TELESPAN, INC. ("THE CUSTOMER"), REPRESENTED BY CHARLES
RANDY POOLE, LEGAL REPRESENTATIVE IN ACCORDANCE WITH THE FOLLOWING BACKGROUND,
RECITALS, AND CLAUSES:

                                   BACKGROUND

1.   On April 28, 1998 SATMEX and the Customer executed Agreement No. 095-1
     ("the Agreement") for the provision of International Satellite Services via
     the Mexican Satellite System.

1.   On September 1, 1998 SATMEX and the Customer executed an Amendment
     ("Amendment 1") to Agreement No. 095-1 for the provision of International
     Satellite Services via the Mexican Satellite System in which it was
     established that the monthly recurring would be $161,000 USD.

1.   On January 4, 1999 SATMEX and the Customer executed an Amendment
     ("Amendment 2") to Agreement No. 095-1 for the provision of International
     Satellite Services via the Mexican Satellite System in which it was
     established that the late payment fees would be calculated based on the
     rate resulting from 1.5 times the Prime Rate issued by Citibank.

1.   In accordance with Paragraph One of the Agreement, SATMEX agreed to provide
     to the Customer international satellite services via the Mexican Satellite
     System by assigning uninterrupted space segment on C Band, transponder 3W,
     Region 1, Solidaridad 2 with a bandwidth of 72 MHz.

                                   RECITALS

 .1   The parties hereby state:

 .1   That they ratify all Recitals stated in the Agreement.

 .1   That they hereby agree to the terms and conditions of this present
     Amendment.

After having made the above statements and recitals the Parties hereby agree to
execute and adhere to the following:

                                    CLAUSES

FIRST.-   The Parties agree that the Bandwidth established in the First
             Paragraph of The Agreement shall be utilized by the Customer as
             follows:

             May 1, 1998 to October 31, 1999          72.00 MHz
             November 1, 1999 to March 31, 2000       36.00 MHz
             April 1, 2000 to July 31, 2000           54.00 MHz
             August 1, 2000 to April 30, 2001         72.00 MHz
SECOND.-     The Parties agree in modifying the First Clause of Amendment
             1 as follows:

             The Customer shall pay SATMEX for the services in advance on a
             monthly basis a total of ************* in accordance with the
             following schedule:

             From May 1, 1998 to October 31, 1999 *********** monthly.

             From November 1, 1999 to March 31, 2000 ********** monthly.

**********   Confidential treatment requested by registrant. Omitted material
             filed separately with the Commission.

                                      21
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             From April 1, 2000 to July 31, 2000 *********** monthly.

             From August 1, 2000 to April 30, 2001 *********** monthly.

SECOND.-     The Parties agree in substituting Addendum 1 of Amendment 1 for
             Addendum 1-b attached hereto and duly executed by the parties and
             shall form an integral part of this Amendment.

THIRD.-      The term of this Amendment shall begin upon the date of execution
             and shall terminate in accordance with the term established in
             Paragraph Fourteen of the Agreement.

FOURTH.-     The Parties agree that all other Paragraphs of the Agreement,
             Amendment 1, and Amendment 2 as well as all other Addenda shall
             prevail as agreed to.

FIFTH.-      For everything relating to the fulfillment, contents,
             interpretation and scope of this Amendment as well as that not
             expressly stated herein, the Parties agree to submit to the
             established in the Civil Code of the Federal District and the
             jurisdiction and competence of the Federal Courts located in Mexico
             City waiving the right to any other jurisdiction future or present
             and for any reason whatsoever.

This Amendment is executed in duplicate with each party retaining an original in
Mexico City on November 1, 1999.

             SATMEX                         CUSTOMER

 ING. LAURO GONZALEZ MORENO          CHARLES RANDY POOLE
      GENERAL DIRECTOR               LEGAL REPRESENTATIVE

*********** Confidential treatment requested by registrant. Omitted material
filed separately with the Commission.

                                      22
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                            TECHNICAL ADDENDUM I-b

                              GENERAL INFORMATION

Customer:     TELESPAN, INC.
Address:      12500 NETWORK BOULEVARD, SUITE 407
City:         SAN ANTONIO TEXAS USA
Contract No.  095-I  Date: April 28, 1998            Term:         3 years
Legal Rep:    CHARLES RANDY POOLE

               TECHNICAL INFORMATION OF ASSIGNED CAPACITY

Type of Network: POINT TO POINT       Bandwidth:
May 1, 1998-October 31, 1999          72.00 MHz
November 1, 1999-March 31, 2000       36.00 MHz
April 1, 2000-July 31, 2000           54.00 MHz
August 1, 2000-April 30, 2001         72.00 MHz

Type:          PRIVATE NETWORK
Satellite:         SOLIDARIDAD 2    Band: C      Service Category: Uninterrupted
Orbital Position:  113(degrees) 0"  Transponder: 3W
Region:            R1               Polarization: H/V  Connectivity: R1/R1
Teleport:                           SAN ANTONIO, TEXAS

                                     TARIFF

AGREEMENT TERM:          TOTAL AGREEMENT ************* USD
THREE YEARS
                         MONTHLY RECURRING:

                         May 1, 1998-October 31, 1999         ***********
                         November 1, 1999-March 31, 2000      ***********
                         April 1, 2000-July 31, 2000          ***********
                         August 1, 2000-April 30, 2001        ***********

Commencement Date: May 1, 1998  Termination Date: April 30, 2001

Mexico, D.F. November 1, 1999

          SATMEX                            THE CUSTOMER

     ING. LAURO ANDRES GONZALEZ MORENO      CHARLES RANDY POOLE
          PRESIDENT                           PRESIDENT

**********   Confidential treatment requested by registrant. Omitted material
             filed separately with the Commission.

                                      23<PAGE>

                                                                    Exhibit 10.6

ADDENDUM TO THE AGREEMENT FOR PRIVATE LINE SERVICES NUMBER 100948-0011 FOR
PROVISION OF TELECOMMUNICATION SERVICES

This Addendum forms an integral part of the Master Telecommunications Services
Agreement (Master Agreement).  The information contained herein will be governed
by the terms and conditions established in the Master Agreement executed between
American Telesource International, Inc.  (The "CUSTOMER") and BESTEL, S.A. DE
C.V. ("BESTEL") dated September 29, 1998.

This document may be modified or added to as necessary in the understanding that
in order to form and become an integral part of the Master Agreement, it should
be executed by the parties authorized legal representatives.

In the event that this Addendum is substituted by another or other Addenda,
these must maintain consecutive numbering taking into account the letter of the
Addendum, with the last Addendum being the document in effect for both parties.

Without prejudice of the above and as established in the Master Agreement, the
Addenda corresponding to Services and/or Promotional Programs selected by the
CUSTOMER at a date later than the execution date of the Master Agreement, will
become effective as of the date of implementation of Services.

1.  DESCRIPTION AND COST OF PRIVATE LINE SERVICES.

          1 International DS3 link Mexico, D.F. - San Antonio, Tx
          -------------------------------------------------------

     --------------------------------------------------------------------------
             Circuit                         Installation     Monthly Recurring
                                             (Pesos)          (Pesos)
     --------------------------------------------------------------------------
     1 International DS3 Mexico - Laredo          $0.00            xxxxxxxxxxx
     --------------------------------------------------------------------------
     DS3 Laredo, Tx - San Antonio, Tx             $0.00            xxxxxxxxxxx
     --------------------------------------------------------------------------

The CUSTOMER shall provide and maintain all necessary equipment for these
circuits.

These prices include the complete international circuit, including the local
loops on both sides of the border.

As of the date of execution of this Addendum, the CUSTOMER has not elected the
option of adding an "ADD/DROP" in Monterrey; however, if the CUSTOMER should
decide to do so, the monthly rate will be $18,512.00.

2.  TERM

2.1 This Addendum shall be for 3 (three) years; however, either party may
request in writing the termination with at least 1 calendar month in advance of
the desired termination date, observing the obligations established herein.

3.  CONSIDERATION

xxxxx - Confidential treatment requested by registrant. Omitted materials filed
separately with the Commission.

                                      31
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3.1  The CUSTOMER shall pay BESTEL for the services provided the amount
specified above in Section 1 of this document or the amount specified on the
invoice by no later than the due date shown on the invoice. BESTEL shall be able
to collect any amount established in the tariff rates of the selected
Promotional Program and accepted by the CUSTOMER.

3.2  In the event the CUSTOMER decides to terminate the services of this
Addendum, the CUSTOMER shall be responsible for payment of the 100% of the
amounts resulting from the remaining time left based on 2.1 of this Addendum.

For this paragraph, the CUSTOMER shall always observe the specified in the
Master Agreement.

4.   RESPONSIBILITIES

4.1  The CUSTOMER shall be responsible for the use of the services contracted.

4.2  BESTEL shall not be responsible for the use, negligence, fraudulent use,
contrary use against service specifications, illegal and/or unauthorized use by
the CUSTOMER.

4.3  BESTEL shall not be responsible for any authorization, permit, license
needed by the CUSTOMER in regards to this Agreement.

4.4  The CUSTOMER shall observe at all times the Intellectual Property Law and
shall respond to all and each of any claims presented directly by or indirectly
against BESTEL, The CUSTOMER shall indemnify and hold BESTEL harmless from and
against any claim.  Such indemnification shall include any legal expenses that
BESTEL might incur.

     The parties hereby agree and execute this Addendum in duplicate in Mexico
City, D.F. on March 16, 1999.

THE CUSTOMER                                      BESTEL
AMERICAN TELESOURCE INTERNATIONAL, INC.           BESTEL, S.A. DE C.V.

(Signature)                                       (Signatures)
By: Mr. Charles R. Poole                 By: Lic. Ignacio de J. Romo Davila
Title: President                                  Ing. Pablo J. Galindo Tovar
                                                  Title: Legal Representatives

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