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                                                                   Page 1 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

Exhibit 10.48.4

Omitted information, for which [ * ] has been substituted herein, has been
omitted pursuant to a request for confidential treatment and such information
has been filed separately with the office of the Secretary of the Securities and
Exchange Commission.


CUSTOMER Name (Full Legal Name): Easylink Services Corporation

Date of execution of Agreement:                 10/01/01           (by CUSTOMER)

                                                                   (by AT&T)

================================================================================

1.    Services Provided. AT&T will provide the following Services to CUSTOMER
      under this Attachment and pursuant to the terms of the Agreement and the
      applicable Tariffs specified below.

      A.    AT&T MEGACOM(R) Service. AT&T MEGACOM Service (AT&T Tariff F.C.C.
            No. 1, as amended from time to time) consisting of AT&T MEGACOM
            Service, including the International Calling Capability.

      B.    AT&T MEGACOM 800 Services. AT&T MEGACOM 800 Services (AT&T Tariff
            F.C.C. No. 2, as amended from time to time) consisting of AT&T
            MEGACOM 800 Service, AT&T MEGACOM 800 Service-Canada, AT&T MEGACOM
            800 Service-Mexico, and AT&T MEGACOM 800 Service-Overseas.

      C.    Access Connections. AT&T Private Line Service (AT&T Tariff F.C.C.
            No. 9, as amended from time to time) consisting of AT&T ACCUNET T1.5
            Service Access Connections.

      D.    AT&T Local Channel Services. AT&T Local Channel Services (AT&T
            Tariff F.C.C. No. 11, as amended from time to time) consisting of
            AT&T TERRESTRIAL 1.544 Mbps Local Channel Services.

2.    Term. The Term of this Attachment is one year. For each Service provided
      under this Attachment, the Term begins on the first day of the bill cycle
      for that Service, during the first full billing month for the first
      Service provided under this Attachment. The first day of the first full
      billing month for the first Service provided under this Attachment is
      referred to as the Customer's Initial Service Date (CISD). Different
      Services may have different billing cycles, and so the billing months may
      be staggered. For each Service, however, the Term will begin less than one
      month after the CISD.

3.    Minimum Revenue Commitments. There are no Minimum Revenue Commitments
      under this Attachment.

4.    Rates and Charges. The rates and charges for the Services provided under
      this Attachment are the same as the undiscounted rates and charges under
      the applicable Tariffs, as amended from time to time, except as specified
      in this Attachment. AT&T reserves the right to change from time to time
      the rates for Services under this Agreement, regardless of any provisions
      that would otherwise stabilize rates or limit rate increases, to
      reasonably reflect charges or payment obligations imposed on AT&T stemming
      from an order, rule or regulation of the Federal Communications Commission
      or a court of competent jurisdiction, or any other governmental entity or
      authority, concerning (i) compensation of payphone service providers, (ii)
      universal service fund ("USF") charges, (iii) presubscribed interexchange
      carrier charges ("PICCs"), or (iv) other governmental charges or fees
      imposed in connection with the provision of Services, or to reasonably
      reflect charges or payment obligations imposed on AT&T related to
      termination of domestic or international calls to mobile numbers.

                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

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                                                                   Page 2 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing


      A.    AT&T MEGACOM 800 Services.

            1.    AT&T MEGACOM 800 Service. The following usage rate applies in
                  lieu of the Usage Charges specified in Tariff F.C.C. No. 2 for
                  calls from all domestic Service Areas: [*]

            2.    AT&T MEGACOM 800 Service- International. The rates listed
                  below apply for all Rate Steps and/or Rate Areas and for all
                  rate periods and are billed in Initial Period of 30 Seconds or
                  Fraction thereof and Additional Period of 1 Second or Fraction
                  thereof.


                   -------------------------------------------------------------
                       Country/Area                      Per Country
                   -------------------------------------------------------------
                          Canada                             [*]
                   -------------------------------------------------------------


      B.    AT&T MEGACOM Service.

            1.    Domestic Rates. The following usage rate applies in lieu of
                  the AT&T MEGACOM Service Schedule A and Schedule B usage rates
                  specified in Tariff F.C.C. No. I for domestic calls.

                  --------------------------------------------------------------
                   Initial 18 seconds               Each Additional 6 seconds
                      or fraction                        or fraction
                  --------------------------------------------------------------
                         [*]                                   [*]
                  --------------------------------------------------------------


            2.    International Rates

                  (a)   Mexico Rate Schedule - The following usage rates apply
                        in lieu of the AT&T MEGACOM Service International
                        Calling Capability Mexico Rate Schedule usage rates
                        specified in AT&T Tariff F.C.C. No. I for calls to
                        Mexico. These usage rates are for both the portion of
                        the call between the U.S. Mainland and the point of
                        connection at the international boundary and the portion
                        of the call between the point of connection at the
                        international boundary and Mexico.


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

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                                                                   Page 3 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing


                        --------------------------------------------------------
                        Mexico        Per Minute Peak       Per Minute Off-Peak
                        --------------------------------------------------------
                                            [*]                     [*]
                        --------------------------------------------------------


                  (b)   All Other Countries - The following usage rates apply in
                        lieu of the AT&T MEGACOM Service International Calling
                        Capability usage rates specified in AT&T Tariff F.C.C.
                        No. 1 for calls to the listed countries and are billed
                        in an initial 30 second or fraction and each additional
                        6 second or fraction rate period(s). Other Line Charges
                        may also apply for calls to Canada,

                      ----------------------------------------------------------
                      Country                                 Rate Per Minute
                      ----------------------------------------------------------

                      Albania                                    [*]
                      Algeria                                    [*]
                      American Samoa                             [*]
                      Andorra                                    [*]
                      Angola                                     [*]
                      Anguilla                                   [*]
                      Antarctica (Casey)                         [*]
                      Antarctica (Scott)                         [*]
                      Antigua & Barbuda                          [*]
                      Argentina                                  [*]
                      Armenia                                    [*]
                      Aruba                                      [*]
                      Ascension Island                           [*]
                      Australia                                  [*]
                      Australia (Mobile)                         [*]
                      Austria                                    [*]
                      Austria (Mobile)                           [*]
                      Azerbaijan                                  [*]
                      Bahamas                                     [*]
                      Bahrain                                     [*]
                      Bangladesh                                  [*]
                      Barbados                                    [*]
                      Belarus                                     [*]
                      Belgium                                     [*]
                      Belgium (Mobile)                            [*]
                      Belize                                      [*]




                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

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                                                                   Page 4 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      Benin                                       [*]
                      Bermuda                                     [*]
                      Bhutan                                      [*]
                      Bolivia                                     [*]
                      Bosnia & Herzegovina                        [*]
                      Botswana                                    [*]
                      Brazil                                      [*]
                      Brazil (Mobile)                             [*]
                      British Virgin Islands                      [*]
                      Brunei                                      [*]
                      Bulgaria                                    [*]
                      Burkina Faso                                [*]
                      Burma (Myanmar)                             [*]
                      Burundi                                     [*]
                      Cambodia                                    [*]
                      Cameroon                                    [*]
                      Canada                                      [*]
                      Cape Verde Islands                          [*]
                      Cayman Islands                              [*]
                      Central Africa                              [*]
                      Chad Republic                               [*]
                      Chile                                       [*]
                      Chile (Mobile)                              [*]
                      China                                       [*]
                      Christmas & Cocos Islands                   [*]
                      Colombia                                    [*]
                      Comoros                                     [*]
                      Congo Republic                              [*]
                      Cook Islands                                [*]
                      Costa Rica                                  [*]
                      Croatia                                     [*]
                      Cuba                                        [*]
                      Cyprus                                      [*]
                      Czech Republic                              [*]
                      Denmark                                     [*]
                      Denmark (Mobile)                            [*]
                      Diego Garcia                                [*]
                      Djibouti Republic                           [*]
                      Dominica                                    [*]
                      Dominican Republic                          [*]
                      Ecuador                                     [*]
                      Egypt                                       [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

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                                                                   Page 5 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      El Salvador                                 [*]
                      Equatorial Guinea                           [*]
                      Eritrea                                     [*]
                      Estonia                                     [*]
                      Ethiopia                                    [*]
                      Faeroe Island                               [*]
                      Falkland Islands                            [*]
                      Federated States of Micronesia              [*]
                      Fiji Islands                                [*]
                      Finland                                     [*]
                      Finland (Mobile)                            [*]
                      France                                      [*]
                      France (Mobile)                             [*]
                      French Antilles                             [*]
                      French Guiana                               [*]
                      French Polynesia                            [*]
                      Gabon Republic                              [*]
                      Gambia                                      [*]
                      Georgia                                     [*]
                      Germany                                     [*]
                      Germany (Mobile)                            [*]
                      Ghana                                       [*]
                      Gibraltar                                   [*]
                      Greece                                      [*]
                      Greenland                                   [*]
                      Grenada                                     [*]
                      Guantanamo Bay                              [*]
                      Guatemala                                   [*]
                      Guinea Bissau                               [*]
                      Guinea Republic                             [*]
                      Guyana                                      [*]
                      Haiti                                       [*]
                      Honduras                                    [*]
                      Hong Kong                                   [*]
                      Hungary                                     [*]
                      Hungary (Mobile)                            [*]
                      Iceland                                     [*]
                      India                                       [*]
                      Indonesia                                   [*]
                      Iran                                        [*]
                      Iraq                                        [*]
                      Ireland                                     [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

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                                                                   Page 6 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      Ireland (Mobile)                            [*]
                      Israel                                      [*]
                      Israel (Mobile)                             [*]
                      Italy                                       [*]
                      Italy (Mobile)                              [*]
                      Ivory Coast                                 [*]
                      Jamaica                                     [*]
                      Japan                                       [*]
                      Japan (Mobile)                              [*]
                      Jordan                                      [*]
                      Kazakhstan                                  [*]
                      Kenya                                       [*]
                      Kiribati                                    [*]
                      Kuwait                                      [*]
                      Kyrgyzstan                                  [*]
                      Laos                                        [*]
                      Latvia                                      [*]
                      Lebanon                                     [*]
                      Lesotho                                     [*]
                      Liberia                                     [*]
                      Libya                                       [*]
                      Liechtenstein                               [*]
                      Lithuania                                   [*]
                      Luxembourg                                 [*]
                      Macao                                      [*]
                      Macedonia                                  [*]
                      Madagascar                                 [*]
                      Malawi                                     [*]
                      Malaysia                                   [*]
                      Maldives                                   [*]
                      Mali Republic                              [*]
                      Malta                                      [*]
                      Marshall Island                            [*]
                      Mauritania                                 [*]
                      Mauritius                                  [*]
                      Mayotte Island                             [*]
                      Mexico Off Peak                            [*]
                      Mexico Peak                                [*]
                      Moldova                                    [*]
                      Monaco                                     [*]
                      Mongolia                                   [*]
                      Montserrat                                 [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

<PAGE>

                                                                   Page 7 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      Morocco                                    [*]
                      Mozambique                                 [*]
                      Namibia                                    [*]
                      Nauru                                      [*]
                      Nepal                                      [*]
                      Netherlands                                [*]
                      Netherlands (Mobile)                       [*]
                      Netherlands Antilles                       [*]
                      New Caledonia                              [*]
                      New Zealand                                [*]
                      Now Zealand (Mobile)                       [*]
                      Nicaragua                                  [*]
                      Niger Republic                             [*]
                      Nigeria                                    [*]
                      Niue Islands                               [*]
                      Norfolk Island                             [*]
                      North Korea                                [*]
                      Nor-way                                    [*]
                      Norway (Mobile)                            [*]
                      Oman                                       [*]
                      Pakistan                                   [*]
                      Palau Republic                             [*]
                      Panama                                     [*]
                      Papua New Guinea                           [*]
                      Paraguay                                   [*]
                      Peru                                       [*]
                      Philippines                                [*]
                      Philippines (Mobile)                       [*]
                      Poland                                     [*]
                      Poland (Mobile)                            [*]
                      Portugal                                   [*]
                      Portugal (Mobile)                          [*]
                      Qatar                                      [*]
                      Reunion Island                             [*]
                      Romania                                    [*]
                      Russia                                     [*]
                      Rwanda                                     [*]
                      San Marino                                 [*]
                      Sao Tome                                   [*]
                      Saudi Arabia                               [*]
                      Senegal                                    [*]
                      Serbia (Yugoslavia)                        [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

<PAGE>

                                                                   Page 8 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      Seychelles Island                          [*]
                      Sierra Leone                               [*]
                      Singapore                                  [*]
                      Slovakia                                   [*]
                      Slovenia                                   [*]
                      Solomon Island                             [*]
                      Somalia                                    [*]
                      South Africa                               [*]
                      South Korea                                [*]
                      South Korea (Mobile)                       [*]
                      Spain                                      [*]
                      Spain (Mobile)                             [*]
                      Sri Lanka                                  [*]
                      St Helena                                  [*]
                      St Kitts & Nevis                           [*]
                      St Lucia                                   [*]
                      St Pierre & Miquelon                       [*]
                      St Vincent & Grenadines                    [*]
                      Sudan                                      [*]
                      Suriname                                   [*]
                      Swaziland                                  [*]
                      Sweden                                     [*]
                      Sweden (Mobile)                            [*]
                      Switzerland                                [*]
                      Switzerland (Mobile)                       [*]
                      Syria                                      [*]
                      Taiwan                                     [*]
                      Taiwan (Mobile)                            [*]
                      Tajikistan                                 [*]
                      Tanzania                                   [*]
                      Thailand                                   [*]
                      Togo                                       [*]
                      Tonga Islands                              [*]
                      Trinidad & Tobago                          [*]
                      Tunisia                                    [*]
                      Turkey                                     [*]
                      Turkmenistan                               [*]
                      Turks & Caicos Islands                     [*]
                      Tuvalu                                     [*]
                      Uganda                                     [*]
                      Ukraine                                    [*]
                      United Arab Emirates                       [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

<PAGE>

                                                                   Page 9 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

                      United Kingdom                             [*]
                      United Kingdom (Mobile)                    [*]
                      Uruguay                                    [*]
                      Uzbekistan                                 [*]
                      Vanuatu                                    [*]
                      Venezuela                                  [*]
                      Venezuela (Mobile)                         [*]
                      Vietnam                                    [*]
                      Wallis Island                              [*]
                      Western Samoa                              [*]
                      Yemen Republic                             [*]
                      Zaire                                      [*]
                      Zambia                                     [*]
                      Zimbabwe                                   [*]

                  (c)   International Rate Adjustments - AT&T shall have the
                        right to change the AT&T MEGACOM Service International
                        rates on [*] written notice to Customer at any time over
                        the course of the Term.

      5.    Discounts. The following discounts are the only discounts that apply
            to the Services provided under this Attachment.

            A.    AT&T MEGACOM 800 Service. The following discounts for AT&T
                  MEGACOM 800 Service are applied to AT&T MEGACOM 800 Service
                  usage charges each month.

                  1.    Domestic Discounts. For usage occurring during the
                        months of October-November-December 2001 and January,
                        2002 only the following discount will be applied to all
                        monthly domestic AT&T MEGACOM 800 Service usage charges,
                        depending on the amount of total monthly usage charges
                        for domestic AT&T MEGACOM 800 Service. Discounts are
                        calculated based on domestic usage charges (interstate
                        and intrastate). If application of the discount to
                        intrastate usage charges is not permitted, the amount of
                        the discount will be calculated based on total domestic
                        usage charges, and that full amount will be applied only
                        against interstate charges.


                        --------------------------------------------------------
                         Total Applicable Monthly Usage Charges     Discount
                        --------------------------------------------------------
                                           [*]                         [*]
                        --------------------------------------------------------


                  2.    International Discounts. [*].



                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

<PAGE>

                                                                  Page 10 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

            E.    AT&T MEGACOM Service.

                  1.    Domestic Discounts. For usage occurring during the
                        months of [*]only the following discount will be applied
                        to all monthly domestic AT&T MEGACOM Service usage
                        charges for calls. Discounts are calculated based on
                        total domestic usage charges (interstate and
                        intrastate). If application of the discount to
                        intrastate usage charges is not permitted, the amount of
                        the discount will be calculated based on total domestic
                        usage charges, and that full amount will be applied only
                        against interstate charges.


                        -----------------------------------------------------
                        Total Monthly Usage Charges        Discount
                        -----------------------------------------------------
                                    [*]                      [*]
                        -----------------------------------------------------


                  2.    International Discounts. [*].

      6.    Credits and Waivers. The following credits and waivers are the only
            credits and waivers that apply to the Services provided under this
            Attachment. No other promotion credits or waivers apply.

            A.    [*]Waiver. AT&T will waive the [*]associated with the [*]of
                  certain Services or service provided under this Attachment. No
                  waiver applies to Services or service components that are
                  [*]after this Attachment is made part of the Agreement. The
                  maximum combined value of the [*]that will be waived under
                  this Section shall not exceed [*].

                  1.    [*]. A [*]applies for any service components installed
                        subject to a [*] of [*]. If any such service component
                        is disconnected prior to the end of the [*], CUSTOMER
                        will be billed for the [*] previously [*] for that
                        service component.

                  2.    [*]. This [*]applies only to the following charges that
                        would otherwise be incurred for Services provided under
                        this Attachment:

                        (d)   [*]

            F.    [*]. The following [*] will be applied to the Customer's
                  MEGACOM Service Invoice by December, 2001:

                        (a)   [*]

      7.    Monitoring Conditions. If CUSTOMER fails to satisfy any of the
            following Monitoring Conditions during any month of the Term, AT&T
            may assess a Non-compliance Charge. Unless otherwise provided, the
            Non-compliance Charge is equal to [*] of the [*] incurred under this
            Attachment during that month.

            A.    [*]


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions

<PAGE>

                                                                  Page 11 of 11

     AT&T MEGACOM(R) Service and AT&T MEGACOM 800 Service Terms and Pricing

      8.    Classifications, Practices and Regulations. Except as otherwise
            Attachment, the rates and regulations that apply to the Services
            provided under this Attachment are as set forth in the applicable
            Tariffs.

            A.    Detariffing. If, during the Term of this Attachment, any of
                  the tariffs of AT&T referenced herein are canceled, in whole
                  or in part, pursuant to a statutory change, order or
                  requirement of a governmental or judicial authority of
                  competent jurisdiction requiring detariffing, then, following
                  such cancellation, any rates, terms and conditions of such
                  tariffs that had been applicable to the Services provided
                  under this Agreement will continue to apply, based on the
                  language of the tariffs in effect as of the date of
                  cancellation.

            B.    Definitions. Terms not otherwise defined in this Attachment or
                  in the Agreement have the meanings provided in the applicable
                  Tariffs.

      9.    Termination. Either party may terminate this Attachment by notice to
            the other party. The Termination will be effective at the end of the
            first billing month that begins on or after the date notice of
            termination is provided. If CUSTOMER continues to use any of the
            Services after the effective date of such termination, the rates,
            terms and conditions will be as provided in the applicable Tariffs.

================================================================================
                                End of Attachment


                            AT&T/CUSTOMER PROPRIETARY
                      Use Pursuant to Company Instructions