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                                                                     Exhibit 3.4

                                                                File No. 52437-D

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                                 STATE OF ALASKA
                       DEPARTMENT OF COMMERCE AND ECONOMIC
                                   DEVELOPMENT
                DIVISION OF BANKING, SECURITIES AND CORPORATIONS

                                   CERTIFICATE
                                       OF
                                    AMENDMENT
                              BUSINESS CORPORATION

         The undersigned, as Commissioner of Commerce and Economic Development
         of the State of Alaska, hereby certifies that Articles of Amendment to
         the Articles of Incorporation, duly signed and verified pursuant to the
         provisions of the Alaska Corporations Code, have been received in this
         office and have been found to conform to law.

         ACCORDINGLY, the undersigned, as Commissioner of Commerce and Economic
         Development, and by virtue of the authority vested in me by law, hereby
         issues this Certificate of Amendment to the Articles of Incorporation
         of

                            ATU COMMUNICATIONS, INC.

         and attaches hereto the original copy of the Articles of Amendment.


                                        IN TESTIMONY WHEREOF, I execute this
                                        certificate and affix the Great Seal of
                                        the State of Alaska on MAY 24, 1999.

                                        /s/ Deborah B. Sedwick

                                        Deborah B. Sedwick
                                        Commissioner of Commerce
                                           and Economic Development

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                                                              Filed for Record
                                                              State of Alaska

                                                                MAY 24 1999

                                                          Dept. of Commerce
                                                          & Economic Development

                            ARTICLES OF AMENDMENT OF

                          ARTICLES OF INCORPORATION OF

                            ATU COMMUNICATIONS, INC.

         Pursuant to Section 10.06.502 ET SEQ. of the Alaska Corporations Code,
ATU Communications, Inc. hereby adopts the following Articles of Amendment to
its Articles of Incorporation:

                                   ARTICLE I.

         The name of the corporation shall be ATU Communications, Inc.

                                   ARTICLE II.

         Section 3, Article VIII of the Articles of Incorporation is deleted and
the following provision is inserted in its place:

                  SECTION 3. This corporation my enter into contracts and
         otherwise transact business as vendor, purchaser, or otherwise, with
         its directors, officers, and shareholder(s) and with corporations,
         associations, firms and entities in which they are or may be or become
         interested as directors, officers, shareholders, members or otherwise.

                                  ARTICLE III.

         This amendment was approved by the Board of Directors on May 14, 1999,
and by the sole shareholder at a special meeting called for that purpose on May
14, 1999.

                                   ARTICLE IV.

         The number of shares outstanding and entitled to vote is 1,000.
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                                   ARTICLE V.

         The number of shares voting for the amendment was 1,000; no shares
voted against the amendment.

         IN WITNESS WHEREOF, the undersigned have executed these Articles of
Amendment this 20th day of May, 1999.


                                        ATU COMMUNICATIONS, INC.


                                        By:  /s/ MICHAEL E. HOLMSTROM
                                           ---------------------------------
                                                MICHAEL E. HOLMSTROM
                                        Its:    Senior Vice President


                                        By:  /s/ DEAN A. RYLAND
                                           ---------------------------------
                                                DEAN A. RYLAND
                                        Its:    Acting Secretary


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