<PAGE>
                                                                   Exhibit 10.12

                       MCI WORLDCOM NETWORK SERVICES, INC.

Confidential Treatment. The portions of this exhibit that have been replaced
with "[*****]" have been filed separately with the Securities and Exchange
Commission and are the subject of an application for confidential treatment.

                                 AMENDMENT NO. 7

         This Amendment No. 7 (the "AMENDMENT NO. 7") is made this 8th day of
May, 2003, by and between Valor Telecommunications Enterprises, L.L.C.
("CUSTOMER") and MCI WORLDCOM Network Services, Inc. ("MCI"), to those certain
Program Enrollment Terms (the "PET"), to that certain Telecommunications
Services Agreement more particularly described as TSA # VTE - 001019 (the
"TSA"), made by and between Customer and MCI dated September 30, 2000, including
all prior applicable amendments thereto (the "PRIOR AMENDMENTS"). In the event
of any conflict between the terms of the TSA, the PET, any Prior Amendment or
any applicable Attachment and the terms of this Amendment No. 7, the terms of
this Amendment No. 7 shall control. The TSA along with the PET, the Prior
Amendments, all applicable Attachment(s), and this Amendment No. 7 shall
collectively be referred to as the "AGREEMENT". Capitalized terms not defined
herein shall have the meaning ascribed to them in other documents referenced
herein. All references to "MCI WorldCom" in the Agreement including any
attachments, schedules or exhibits thereto, will be deemed to refer to "MCI".
This Amendment No. 7 does not constitute the assumption of the Agreement as that
term is used under applicable bankruptcy law.

         In consideration of good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

1.       SPECIAL RATES:

         (A)      Notwithstanding anything to the contrary contained in the
                  Agreement or the Attachment for CLASSIC SWITCHLESS/END USER
                  DEDICATED Services, commencing within ten (10) business days
                  following the date this Amendment No. 7 has been fully
                  executed by both parties and delivered to Customer, Customer's
                  rates for CLASSIC SWITCHLESS 1+ Service will be the respective
                  rates set forth below. All other rates will be as set forth in
                  the Agreement or the Attachment for CLASSIC SWITCHLESS/END
                  USER DEDICATED Services.

                  (i)      CLASSIC SWITCHLESS 1+ Service - Customer's special
         INTERNATIONAL rates for calls to the following countr(ies) will be the
         respective rates per minute set forth on Exhibit No. 1 attached hereto.
         [NOTE: INTERNATIONAL RATES ARE FOR LANDLINE CALLS ONLY, UNLESS
         SPECIFICALLY PROVIDED OTHERWISE.]

         (B)      Notwithstanding anything to the contrary contained in the TSA,
                  MCI reserves the right to modify the rates described in
                  Subsection (A) above (which charge modifications shall not
                  exceed then-current generally available MCI charges for
                  comparable services), upon not less than seven (7) calendar
                  days' prior notice to Customer (facsimile being acceptable),
                  which notice will state the effective date for the charge
                  modification.

                                   Page 1 of 2
                                  CONFIDENTIAL

<PAGE>

2.       OTHER TERMS AND CONDITIONS. Except as specifically amended or modified
         herein, the terms and conditions of the Agreement will remain in full
         force and effect throughout the Service Term and any extensions
         thereof.

         IN WITNESS WHEREOF, the parties have entered into this Amendment No. 7
on the date first written above.

VALOR TELECOMMUNICATIONS                MCI WORLDCOM NETWORK
ENTERPRISES, L.L.C.                     SERVICES, INC.

By: /s/ Jack Mueller                    By: /s/ Peter M. Cassidy
    ---------------------------------       ------------------------------------

            Jack Mueller                           Peter M. Cassidy
    ---------------------------------       ------------------------------------
            (Print Name)                             (Print Name)

President and Chief Operating Officer   Vice President, UUNET Wholesale Network
                                                       Services
-------------------------------------   ----------------------------------------
               (Title)                                  (Title)

                5/8/03                                  5/14/03
    ---------------------------------       ------------------------------------
                (Date)                                  (Date)

Attachment:

         Exhibit No. 1 - Special Rates

                                   Page 2 of 2
                                  CONFIDENTIAL

<PAGE>

                                   EXHIBIT 1
                             CLASSIC INTERNATIONAL

<TABLE>
<CAPTION>
       COUNTRY                          SWITCHLESS 1+
----------------------                  -------------
<S>                                     <C>
Argentina                                  [*****]
Argentina Buenos Aires                     [*****]
Argentina Cordoba                          [*****]
Argentina Mendoza                          [*****]
Argentina Mobile                           [*****]
Argentina Rosario                          [*****]
Belize                                     [*****]
Bolivia                                    [*****]
Bolivia Cochambamba                        [*****]
Bolivia La Paz                             [*****]
Bolivia Mobile                             [*****]
Bolivia Santa Cruz                         [*****]
Brazil                                     [*****]
Brazil Belem                               [*****]
Brazil Belo Horizonte                      [*****]
Brazil Brasilia                            [*****]
Brazil Campinas                            [*****]
Brazil Curitibia                           [*****]
Brazil Florianopolis                       [*****]
Brazil Fortaleza                           [*****]
Brazil Goiania                             [*****]
Brazil Manaus                              [*****]
Brazil Mobile                              [*****]
Brazil Porto Alegre                        [*****]
Brazil Recife                              [*****]
Brazil Rio de Janeiro                      [*****]
Brazil Salvador                            [*****]
Brazil Sao Paulo                           [*****]
Brazil Vitoria                             [*****]
Chile                                      [*****]
Chile Mobile                               [*****]
Columbia                                   [*****]
Columbia Barranquilla                      [*****]
Columbia Bogota                            [*****]
Colombia Cali                              [*****]
Colombia Medellin                          [*****]
Colombia Mobile                            [*****]
Costa Rica                                 [*****]
Costa Rica Mobile                          [*****]
El Salvador                                [*****]
El Salvador Mobile                         [*****]
</TABLE>

Valor Amd 7 Exhibit 1
                                                                     Page 1 of 2

<PAGE>

                                   EXHIBIT 1
                             CLASSIC INTERNATIONAL

<TABLE>
<CAPTION>
       COUNTRY                          SWITCHLESS 1+
----------------------                  -------------
<S>                                     <C>
Grenada                                    [*****]
Honduras                                   [*****]
Nicaragua                                  [*****]
Nicaragua Mobile                           [*****]
Panama                                     [*****]
Panama Mobile                              [*****]
Paraguay                                   [*****]
Paraguay Mobile                            [*****]
Peru                                       [*****]
Peru Lima                                  [*****]
Peru Mobile                                [*****]
Uruguay                                    [*****]
Uruguay Mobile                             [*****]
Venezuela                                  [*****]
Venezuela Caracas                          [*****]
Venezuela Maracaibo                        [*****]
Venezuela Mobile                           [*****]
Venezuela Valencia                         [*****]
</TABLE>

Valor Amd 7 Exhibit 1
                                                                     Page 2 of 2