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                                                                   EXHIBIT 10.46



                                 AMENDMENT NO. 6
                                       TO
                      PCS 1900 PROJECT AND SUPPLY AGREEMENT
                                     BETWEEN
                        VOICESTREAM WIRELESS CORPORATION
                                       AND
                              NORTEL NETWORKS INC.


This Agreement is made as of this 14th day of May, 1999 ("Effective Date No.
6"), by and between VoiceStream Wireless Corporation, a Washington corporation
with offices located at 3650 131st Avenue SE, Bellevue, Washington 98006
("Buyer") and Nortel Networks Inc. (formerly Northern Telecom Inc.), a Delaware
corporation with offices located at 2221 Lakeside Boulevard, Richardson, Texas
75082 (hereinafter referred to as "Seller").

WHEREAS, Buyer's predecessor in interest, VoiceStream Wireless Corporation
(formerly known as Western PCS Corporation, a Delaware corporation ("WPCS")) and
Seller entered into a PCS 1900 Project and Supply Agreement dated June 30, 1995
(as heretofore amended by Amendments No. 1-5, as amended hereby and as hereafter
amended the "Supply Agreement"); and

WHEREAS, on April 9th, 1999 WPCS was merged with and into Buyer in order to
effect a reincorporation of WPCS in Washington State and, accordingly, Buyer
succeeded to all of WPCS's rights and obligations under the Supply Agreement;
and

WHEREAS, Buyer and Seller now wish to further amend the Supply Agreement by
adding additional terms and conditions associated with, among other things,
Buyer's acquisition of Seller's Equipment and Services for deployment in certain
new markets and expansions of existing markets and revising the discount
structure.

NOW, THEREFORE, in consideration of the mutual covenants herein contained, Buyer
and Seller agree to amend the Supply Agreement as follows:

1.      (a)    Amend the definition of the term "Buyer" so that it includes not
only VoiceStream Wireless Corporation, but also any entity in which VoiceStream
Wireless Corporation owns directly or indirectly more than fifty percent (50%)
of the equity or voting power.

        (b)    Amend Article 1, Section 1.1 "Add-on Equipment" by deleting it in
its entirety and replacing it with the following:

               1.1    "Add-on Equipment" shall mean Equipment other than the
                      Equipment initially provided for Buyer's Network as set
                      forth in Section 1.1 through


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                                                                   EXHIBIT 10.46


                      1.5 of Annex 1 (as amended) and the Equipment provided for
                      the Initial Build of New Markets.

        (c)    Amend Article 1, Section 1.12 "Initial Network" by deleting it in
its entirety and replacing it with the following:

               1.12   "Initial Network" shall mean any market other than a New
                      Market.

        (d)    Amend Article 1, by adding the following new Section 1.20, and
renumbering the remaining Sections accordingly:

               1.20   "New Market" shall mean any of the following markets: (i)
                      the San Antonio, Texas market, (ii) the Austin, Texas
                      market, (iii) the Chicago, Illinois market, (iv) the
                      Milwaukee, Wisconsin market, (v) the Dallas, Texas market,
                      (vi) any other U.S. market for which Buyer acquires, after
                      Effective Date No. 6, a license to operate, (vii) any U.S.
                      market for which Buyer has a license but for which as of
                      Effective Date No. 6, Buyer has not constructed a System
                      or (viii) expansions of existing markets into BTAs in
                      which Buyer is not operating as of Effective Date No. 6.
                      The foregoing markets are referred to herein collectively
                      as "New Markets". Buyer and Seller shall mutually agree
                      upon a Statement of Work/Project Schedule (Annex 2) and an
                      Initial Project Schedule (Annex 9) for each New Market,
                      with respect to which Buyer elects to order Equipment
                      and/or Services from Seller. Except as expressly set forth
                      in Section 5.9 (as amended by this Amendment No. 6), Buyer
                      shall not be required to order Equipment or Services for a
                      New Market from Seller.

2.      Amend Article 1, Section 1.36 "Term" (as heretofore amended by Amendment
No. 4) by deleting the words ...*... and replacing them with the words ...*...

3.      Amend Article 1, Section 1.37 "Warranty Period" by adding the following
new Subsections:

               1.37.2.1      With respect to NSS Hardware (excluding OEM
               Equipment) installed after Effective Date No. 6, a period of
               ...*... from the date of Commissioning.

               1.37.3.1      With respect to Software installed after Effective
               Date No. 6, a period of ...*... from the date of Installation of
               the basic operating Software onto the Hardware, which ...*...
               period shall commence with Installation of each new Software
               release licensed for use by Buyer.


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                                                                   EXHIBIT 10.46


               1.37.4.1      With respect to Merchandise installed after
               Effective Date No. 6, a period of ...*... from the shipment date
               of such Merchandise.

4.      Amend Article 5, Section 5.9 by deleting it and restating it in its
entirety as follows:

               "Buyer understands that it has a firm obligation to purchase,
               license and take delivery of no less than ...*... of Equipment
               and Services (net of discounts and incentives but before credits
               and before Handset Funds) from Seller during the Term of this
               Supply Agreement (the "Commitment"). Such Commitment includes
               Buyer's award to Seller of the "Initial Build" of the ...*...
               markets. For the purposes of this Supply Agreement, Initial Build
               shall mean the minimum configuration of NSS and BSS Equipment
               required to support commercial launch by Buyer in a market.

               If funding is made available by Seller to Cook Inlet Voice Stream
               PCS L.L.C. ("CIVS") per a separate financing agreement with
               substantially the same terms as specified in Exhibits A and B
               attached hereto (the "CIVS Facilities"), this Supply Agreement
               will be deemed amended to increase the Commitment in the
               following manner:

                      (a)    If CIVS acquires the Chicago BTA license and the
                      Dallas BTA license, by final grant from the FCC, or
                      earlier than final grant at Buyer's sole discretion, then
                      CIVS/Buyer will award the Initial Build of the Chicago and
                      Dallas markets to Seller and the increase in the
                      Commitment is equal to x, where x equals the amount
                      calculated by multiplying the Applicable Percentage times
                      ...*.... In this case, the Applicable Percentage is
                      calculated as (i) the amount of funds made available by
                      Seller under the CIVS Facilities divided by (ii) ...*...;
                      or

                      (b)    If CIVS does not acquire the Chicago BTA license,
                      but does acquire the Dallas BTA license, by final grant
                      from the FCC, or earlier than final grant at Buyer's sole
                      discretion, then CIVS will award the Initial Build of the
                      Dallas market to Seller and the increase in the Commitment
                      is equal to x, where x equals the amount calculated by
                      multiplying the Applicable Percentage times ...*.... In
                      this case, the Applicable Percentage is calculated as (i)
                      the amount of funds made available by Seller under the
                      CIVS Facilities divided by (ii) ...*....

                      (c)    If CIVS does not acquire the Dallas BTA license,
                      but does acquire the Chicago BTA license, by final grant
                      from the FCC, or earlier than the final grant at Buyer's
                      sole discretion, then CIVS/Buyer will award the Initial
                      Build of the Chicago market to Seller and the increase in
                      the Commitment is equal to x, where x equals the amount
                      calculated by


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                                                                   EXHIBIT 10.46


                      multiplying the Applicable Percentage times ...*.... In
                      this case, the Applicable Percentage is calculated as (i)
                      the amount of funds made available by Seller under the
                      CIVS Facilities divided by (ii) ...*....

                      (d)    If CIVS acquires neither the Chicago nor the Dallas
                      BTA licenses, by final grant from the FCC, then CIVS will
                      award the Initial Build of another combination of licenses
                      for BTAs or groups of BTAs and the increase in the
                      Commitment is equal to x, where x equals the amount
                      calculated by multiplying the Applicable Percentage times
                      ...*.... In this case, the Applicable Percentage is
                      calculated as (i) the amount of funds made available by
                      Seller under the CIVS Facilities divided by (ii) ...*....

               Any such increased Commitment shall be contingent on the
               provision of financing by Seller, the terms of which have been
               substantively agreed on as set forth in the CIVS Facilities.

               The parties agree that if CIVS/Buyer fails without cause to
               satisfy the Commitment applicable under clauses (a), (b), (c) or
               (d) above, then Seller shall not be obligated to extend any
               additional credit under the CIVS Facilities over and above the
               amount of financing that would have been available under the
               above ratios had such Commitment been the amount CIVS/Buyer
               purchased at the time of such failure.

5.      Amend Article 5, by adding the following new Subsections 5.3 and 5.4 and
renumbering the remaining Sections accordingly:

               5.3    With respect to payment for Equipment shipped to New
               Markets for an Initial Build, Seller shall invoice Buyer or CIVS,
               as applicable, in accordance with the following schedule:

               5.3.1  ...*... of the Purchase Order Price shall be invoiced on
               shipment of the Equipment; and

               5.3.2  ...*... of the Purchase Order Price shall be invoiced on
               the date of Final Acceptance.

               5.4    With respect to payment for all Purchase Orders for
               Equipment for the Initial Networks which are issued after
               Effective Date No. 6 and for Purchase Orders for Equipment
               shipped to New Markets which are issued after the Initial Build
               of such New Market, Seller shall invoice Buyer ...*... of the
               Purchase Order Price upon shipment of the Equipment.


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                                                                   EXHIBIT 10.46


               5.4.1  Payments due under Section 5.3 and this Section 5.4 shall
               be paid to Seller within thirty (30) days following the date of
               Seller's invoice therefor.

6.      Amend Subsection 23.1 as follows:

               (a) Amend Subsection 23.1.1 by inserting the words "or
        indirectly" after the word "directly" in the first sentence.

               (b) Add the following new Subsections 23.1.3 and 23.1.4:

               23.1.3 Seller agrees that CIVS and Cook Inlet Western Wireless
               PV/SS PCS L.P. ("Cook Inlet") shall be considered a "Buyer
               Affiliate" for purposes of this Supply Agreement and as such
               shall be entitled to purchase Seller's Equipment and Services
               pursuant to the terms and conditions of this Supply Agreement and
               shall also be entitled to all prices, discounts, incentives,
               credits and Handset Funds set forth in this Supply Agreement. In
               this regard CIVS shall be entitled to all rights and benefits
               available to Cook Inlet under this Supply Agreement and Cook
               Inlet shall be entitled to all the rights and benefits available
               to CIVS under this Supply Agreement. In the event entities other
               than CIVS and/or Cook Inlet become Buyer Affiliates after
               Effective Date No. 6, such entities may, subject to the
               provisions of 23.1.4 place orders pursuant to the terms of this
               Supply Agreement and shall be entitled to all prices, discounts,
               Handset Funds, and incentives, with the exception of: SubSection
               12.10 (as heretofore amended by Amendment No. 4), Section 1.9 and
               SubSection 1.9.1 et. seq., Section 1.10 and SubSection 1.10.1 et.
               seq., Section 1.11 and SubSection 1.11.1, and Section 1.14 set
               forth in Annex 1 (as amended by this Amendment No. 6).

               23.1.4 In the event Buyer or a Buyer Affiliate acquires any
               interest in an entity which (i) as a result of or after such
               acquisition qualifies as a Buyer Affiliate and (ii) has an
               existing contractual agreement with Seller for the supply of GSM
               infrastructure Equipment and Services, Seller agrees that such
               entity may at Buyer's discretion: (a) continue to acquire
               Equipment and Services under its existing contractual agreement
               or (b) immediately commence purchasing Equipment and Services
               pursuant to the terms and conditions of this Supply Agreement. If
               Buyer elects option (b) above, such entity's existing contractual
               agreement to purchase Equipment and Services shall terminate and
               be of no further force or effect except with respect to
               warranties and other provisions relating to Equipment or Services
               purchased prior to such termination; provided, however, that
               option (b) above shall not be available if the acquired entity's
               existing contractual agreement with Seller contains pricing,
               volume purchase and/or exclusivity terms that are tied to the
               provision to such entity of Seller financing, unless applicable
               commitments under such existing contractual agreement have been
               met or such financing has been repaid.


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                                                                   EXHIBIT 10.46


7.      Amend Annex 1 by adding the following new Sections, attached hereto as
Exhibit C (it being understood that Sections 1.6 and the Initial Purchase Order
for the Equipment and Services set forth herein shall be subject to Section 17
of this Supply Agreement respecting Change Orders, including, without
limitation, Sections 17.1, 17.5 and 17.6).

8.      Amend Annex 1, Section 1.7.8 (as heretofore amended by Amendment No. 3)
by inserting the words "or New Market" after the words "each MTA market" or "a
specific MTA".

9.      Amend Annex 1 by adding the following new Sections 1.8.1 - 1.15:

        ...*...

12.     Amend Annex 1, Section 2.2 (amended by Amendment No. 3) by deleting it
in its entirety and replacing it with the following new Section, attached hereto
and incorporated herein as Exhibit E.

Except as specifically modified herein, the Agreement shall in all respects
continue in full force and effect.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 6 to be
duly executed by their representatives being thereunto duly authorized.



VOICESTREAM WIRELESS CORPORATION        NORTEL NETWORKS INC.


By:  /s/ Bob Stapleton                  By:  /s/ Douglas Patterson
--------------------------------        --------------------------------

Name:  Bob Stapleton                    Name:  Douglas Patterson
--------------------------------        --------------------------------

Title:  President                       Title:  VP, Finance
--------------------------------        --------------------------------

Date:  May 14, 1999                     Date:  May 12, 1999
--------------------------------        --------------------------------