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                                                                 Exhibit 10.12.4
                                                                 ---------------

                                    AMENDMENT
                                       TO
                             AGREEMENT OF EMPLOYMENT

     This AMENDMENT TO AGREEMENT OF EMPLOYMENT (this "Amendment"), dated as of
December 19, 2001, is intended to modify the Agreement of Employment, dated as
of April 9, 2000, as amended as of November 15, 2000 (the "Agreement of
Employment"), among Independent Wireless One Corporation, a Delaware corporation
("IWO"), IWO Holdings, Inc., a Delaware corporation ("Holdings" and together
with IWO, the "Corporation") and Steven M. Nielsen (the "Employee"), as modified
by the Letter Agreement, dated September 20, 2000, among Holdings, IWO and the
Employee.

                                    RECITALS

     WHEREAS, the Corporation and the Employee desire to amend the Agreement of
Employment in the manner set forth below.

                                   AGREEMENTS

     NOW THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the parties hereto agree as follows:

     Section 1. Effective immediately prior to and subject to the consummation
     ---------
of a Saints Merger (as defined in Section 2(b) hereof):

     (a) Section 1 of the Agreement of Employment is hereby amended by replacing
the words "until December 31, 2002" therein with the words "until December 31,
2003".

     (b) Section 3(a) of the Agreement of Employment is hereby amended by
replacing the first sentence thereof with the following sentence:

          "The Corporation will pay the Employee during the term hereof for all
          services to be rendered hereunder a basic salary at the rate of two
          hundred thousand dollars ($200,000) per annum from the Effective Date
          through November 15, 2000; two hundred seventy-five thousand dollars
          ($275,000) per annum from November 16, 2000 through December 31, 2001;
          two hundred eighty-five thousand dollars ($285,000) per annum from
          January 1, 2002 to December 31, 2002; and two hundred ninety-five
          thousand dollars ($295,000) per annum from January 1, 2003 to December
          31, 2003.

     (c) Section 7(b)(iii) of the Agreement of Employment is hereby amended by
replacing the last sentence thereof with the following sentence:

          "In the event that this Agreement is terminated pursuant to this
          subparagraph (iii), Employee shall be entitled to payment on the
          Effective Termination Date of an amount equal to (A) the basic salary
          that would be due under paragraph 3(a) for the twelve (12) month
          period following the Effective Termination Date,

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          calculated as if the Employee were employed for such twelve (12) month
          period; plus (B) such cash bonus compensation prorated to the
          Effective Termination Date otherwise due Employee pursuant to
          paragraph 3(b); and (C) the benefits to be paid to Employee pursuant
          to paragraph 3(c), 3(d) and 3(e) prorated to the Effective Termination
          Date."

     Section 2.
     ---------

     (a) You agree that in the case of a Saints Merger, the obligations of the
parties under the Agreement of Employment with respect to Section 2(a) thereof
will be satisfied if you (i) serve as Chief Operating Officer of the entity
("Parent") issuing shares of its capital stock in connection with such Saints
Merger and (ii) perform such duties as are appropriate to such office and not
inconsistent therewith as may be assigned to you by the Chief Executive Officer
of Parent and as presented to the board of directors of Parent for informational
purposes.

     (b) "Saints Merger" means a transaction that (i) results in (x) the merger,
consolidation or amalgamation or other business combination of Holdings with or
into the entity referred to by Holdings as "Saints" or a wholly-owned subsidiary
of Saints or (y) the sale, transfer, assignment, lease, conveyance or other
disposition, directly or indirectly, of all or substantially all the assets of
Holdings and its subsidiaries, considered as a whole, to Saints and (ii) closes
prior to the date occurring 181 days after the signing of a definitive agreement
for such transaction.

     Section 3. This Amendment shall not be effective unless shareholder
     ---------
approval meeting the requirements of Section 280G(b)(5) of the Internal Revenue
Code of 1986, as amended, is obtained.

     Section 4.
     ---------

     (a) This Amendment may be executed in two or more counterparts, each of
which will be deemed an original but which together will constitute one and the
same instrument. Delivery of an executed counterpart of a signature page of this
Amendment by facsimile transmission shall be as effective as delivery of a
manually executed counterpart of this Amendment.

     (b) All references to Section in this Amendment refer to Sections of this
Amendment, unless otherwise expressly provided for.

     (c) All other provisions of the Agreement of Employment not amended hereby
will remain in full force and effect.

                            [signature page follows]

                                       2

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     IN WITNESS WHEREOF, IWO and Holdings have caused this Amendment to be
signed by their respective officers hereunto duly authorized, and the Employee
has hereunto set his hand, effective as of the day and year first above written.

                                                  INDEPENDENT WIRELESS ONE
                                                  CORPORATION


                                                  By: /s/ Timothy J. Medina
                                                      --------------------------
                                                  Name:  Timothy J. Medina
                                                  Title: Chief Financial Officer


                                                  IWO HOLDINGS, INC.


                                                  By: /s/ Timothy J. Medina
                                                      --------------------------
                                                  Name:  Timothy J. Medina
                                                  Title: Chief Financial Officer


                                                  EMPLOYEE


                                                  /s/ Steven M. Nielsen
                                                  ------------------------------
                                                  Steven M. Nielsen