EXHIBIT 10.15.4


                  AMENDMENT NO. 4 TO THE AMENDED AND RESTATED
                   SYSTEM EQUIPMENT PURCHASE AGREEMENT BETWEEN
            LUCENT TECHNOLOGIES INC. AND CRICKET COMMUNICATIONS, INC.


        THIS AMENDMENT NO. 4 (this "Amendment" or "Amendment No. 4") to the
Contract (as defined below) between CRICKET COMMUNICATIONS, INC., a Delaware
corporation (the "Owner" or "Cricket") and LUCENT TECHNOLOGIES INC., a Delaware
corporation (the "Vendor" or "Lucent"), is made effective as of this 10th day of
September, 2002 ("Effective Date").

                                    RECITALS

        WHEREAS, the Owner and Vendor entered into that certain Amended and
Restated System Equipment Purchase Agreement, dated as of June 30, 2000, as
amended by Amendment No. 1, effective March 22, 2002 ("Amendment No. 1"), and
Amendment No. 2, effective March 22, 2002 ("Amendment No. 2"), and Amendment No.
3, effective March 22, 2002 ("Amendment No. 3"); collectively (the "Contract");
and

        WHEREAS, in Amendment No. 1, the Owner and Vendor modified certain
provisions of Section 24.7 of the Contract to provide for certain rights of
Vendor upon the occurrence of certain events; and

        WHEREAS, the Owner and Vendor desire to provide for additional rights of
Vendor with respect to the fulfillment of existing Purchase Orders, and to amend
the provisions of the Contract as they pertain to the acceptance of future
Purchase Orders, as set forth in more detail in this Amendment; and

        WHEREAS, the Owner and Vendor desire to amend the Contract as set forth
herein.

                                   AGREEMENT

        NOW, THEREFORE, in consideration of the mutual promises and covenants
set forth in this Amendment, the Owner and Vendor hereby agree as follows:

A.  AMENDMENTS TO CONTRACT

        1.     Section 3 of the Contract, titled "Purchase Orders and
Schedules," is deleted in its entirety and replaced by the following:

                      3.1 Purchase Orders. (a) The Owner may deliver Purchase
               Orders to the Vendor at any time and from time to time during the
               Contract Term for Products, Services, Software or other items of
               Work to be provided by the Vendor. Such Purchase Orders shall be
               sent to the Vendor either by certified mail, electronic
               transmission or another mutually acceptable manner to the address
               specified in Exhibit L of the Contract. All Purchase Orders shall
               be governed by the terms and conditions of the Contract, unless
               otherwise agreed by the parties in writing. Each Purchase Order
               shall specify, in reasonable detail, the Products, Services,
               Software or other items of Work to be performed by the Vendor.


[*] CERTAIN MATERIAL (INDICATED BY AN ASTERISK) HAS BEEN OMITTED FROM THIS
DOCUMENT PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL
HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.


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                      (b) Every Purchase Order tendered to Vendor by Owner must
               be accompanied by full payment of the prices, fees and charges
               for the Products, Services, Software or Work referenced in such
               Purchase Order, including all such charges and fees as
               transportation charges, taxes, duties and travel and living
               expenses, etc. Owner may request Vendor to quote such prices,
               fees and charges in advance of Owner's submission of the Purchase
               Order, however, tender of such a quote by Vendor shall not
               constitute the advance acceptance of the Purchase Order by
               Vendor. If the price of any of the ordered Products, Services,
               Software or Work or other charges or fees (such as transportation
               charges or travel and living expenses, etc.) cannot be determined
               at the time that Owner submits its Purchase Order to Vendor, or
               at such time that Vendor accepts such Purchase Order as provided
               in Section 3.3(a) below, Vendor shall invoice Owner for such
               items in accordance with the provisions of Section 5.3 of the
               Contract.

                      3.2 Delivery under the Contract. The Vendor shall complete
               the Work specified in each Purchase Order in accordance with the
               terms and conditions of this Contract.

                      3.3 Order Acceptance. (a) All Purchase Orders submitted by
               Owner shall be subject to the written acceptance by Vendor, in
               each instance. Vendor shall acknowledge the date of the order
               receipt either in writing or electronic data interface format,
               and list its committed ship dates by Products, Services, Software
               or Work. The acknowledged date of Purchase Order receipt by
               Vendor is the price-effective date for the Product, Services,
               Software or Work. In the absence of Vendor's written or
               electronic acceptance as provided herein within fourteen (14)
               days of Owner's tender of each Purchase Order, the Purchase
               Order(s) shall be deemed rejected.

                      (b) No provision or data on any Purchase Order or
               contained in any documents attached to or referenced in any
               Purchase Order, or any subordinate document (such as shipping
               releases), which is inconsistent with the terms of this Contract
               shall be binding, except data necessary for Vendor to fill the
               Purchase Order. All such other data and provisions are hereby
               rejected. Electronic Purchase Orders tendered by Owner, and
               subsequently accepted by Vendor as provided in Section 3.3(a)
               above, shall be binding on Owner notwithstanding the absence of a
               signature.

                      (c) Changes made by Owner to a Purchase Order accepted by
               Vendor as provided in Section 3.3(a) above shall be treated as a
               separate Purchase Order subject to Vendor's acceptance unless the
               parties expressly agree otherwise in writing. If any such change
               affects Vendor's ability to meet its obligations under the
               original Purchase Order, any price, shipment date, or completion
               date quoted by Vendor with respect to such original order is
               subject to change and shall be addressed pursuant to the Change
               Order provisions below in Section 11.

                      3.4 Forecasts. Owner shall provide to Vendor regular
               forecasts of Owner's annual Product and Services needs. If the
               quantities ordered are more than 25% greater


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               than forecast quantities, Vendor shall be permitted a reasonable
               extension of time to fulfill such orders and achieve the
               Milestones required of Vendor hereunder.

                      3.5 Deployment Plans and Milestones. The deployment plans
               and intervals, together with the key Milestones, order intervals,
               in respect of each System, are set forth in Exhibit L and in
               Exhibit S.

                      3.6 Inventory Control and Bar-coding. Vendor shall, at no
               additional charge, pack and mark shipping containers in
               accordance with its standard practices for domestic shipments.
               Where in order to meet Owner's requests, Vendor packs and/or is
               required to mark shipping cartons in accordance with Owner's
               specifications, Vendor shall invoice Owner additional charges for
               such packing and/or marking. Vendor shall (a) enclose a packing
               memorandum with each shipment and, if the shipment contains more
               than one package, identify the package containing the memorandum,
               and (b) mark Products as applicable for identification in
               accordance with Vendor's marking specifications (for example,
               model/serial number and month, year of manufacture).

        2.     Section 5.3 of the Contract, titled "Invoicing and Payment," is
deleted in its entirety and replaced by the following:

                      5.3 Invoicing and Payment: (a) Vendor may invoice Owner
               the applicable price(s), charge(s) and fee(s) for any of the
               Products, Services, Software or Work which cannot be determined
               at the time that Owner submits its Purchase Order to Vendor, or
               at the time Vendor accepts such Purchase Order, according to the
               following schedules or as otherwise mutually agreed to in writing
               by Owner and Vendor:

                      (a) one hundred percent (100%) of the applicable price(s),
                      charge(s) and fee(s) for engineering Services which cannot
                      be determined in advance may be invoiced upon completion
                      of such Services;

                      (b) one hundred percent (100%) of the applicable price(s),
                      charge(s) and fee(s) for other Services which cannot be
                      determined in advance may be invoiced monthly in respect
                      of Services rendered during the prior month; and

                      (c) one hundred percent (100%) of the applicable Price(s),
                      charge(s) and fee(s) for any other charges which cannot be
                      determined in advance may be invoiced following the time
                      that they are determined.

                      (b) Vendor invoices shall be issued on a line item basis
               to approximate Owner's Purchase Orders. Such Vendor invoices
               shall also indicate the relevant Owner Purchase Order number.
               Owner shall pay Vendor all invoiced amounts, plus taxes, less any
               disputed items, within thirty (30) days from the date of Vendor's
               invoice. Delinquent payments are subject to a late payment charge
               at an annual rate of [***] per year, or portion thereof, of the
               amount due. However, such late payment charge shall not exceed
               any maximum lawful charges.


[*] CERTAIN MATERIAL (INDICATED BY AN ASTERISK) HAS BEEN OMITTED FROM THIS
DOCUMENT PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL
HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.


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                      (c) Owner shall notify Vendor of any disputed invoice
               amounts in writing within thirty (30) days from the date of the
               invoice. Any disputed amounts which are subsequently determined
               to be valid are due for payment based upon the original invoice
               date and shall be subject to a retroactive late payment charge
               based upon such original invoice due date.

        3.     The unnumbered paragraph which follows Section 24.7(d) of the
Contract (which is the subject of Section 4 of Amendment No. 1) is deleted in
its entirety and replaced by the following new subparagraph 24.7(e):

                      (e) Notwithstanding the existence or absence of any one or
               more of the events described in subsections 24.7(a) through (d)
               above, Vendor, at its sole option, may at any time during the
               Contract Term, take any or all of the following actions with
               respect to any and all Purchase Orders or other contracts for
               Products, Services, Software or Work which have not been
               submitted by Owner and thereafter accepted by Vendor as provided
               by Section 3 (as amended by Amendment No. 4) of this Contract:
               (i) suspend all performance upon any pending Purchase Order; (ii)
               suspend shipment of all Products and Software; (iii) suspend
               performance of all Services and Work; (iv) require revised
               payment terms for the continued provision by Vendor of Products,
               Services, Software and Work; and (v) cancel any outstanding
               Purchase Orders for Products, Services, Software and Work.
               Nothing in this subparagraph (e) shall allow Vendor to suspend
               its performance obligations under Sections 2.8, 12, 13, 14, 15,
               16.3, 18, 19, 20, 23, 24 or 26 of this Contract.

B.      GENERAL TERMS GOVERNING THIS AMENDMENT

        1.     Interpretation: Capitalized terms not otherwise defined herein,
including those used in any attachments hereto, shall have the same meanings as
set forth in the Contract. In the event of any conflict between the terms of
this Amendment and the Contract or any other written agreements between the
parties, the terms of this Amendment shall prevail.

        2.     Full Force and Effect: This Amendment shall become effective as
of the Effective Date, and except as expressly modified in this Amendment, the
Contract, shall remain unmodified and in full force and effect.

        3.     Entire Agreement: This Amendment, together with the Contract,
constitutes the entire agreement between the parties with respect to the subject
matter thereof. No modifications, alterations or waivers of any provision
contained herein shall be binding on the parties hereto unless executed after
the date hereof and evidenced in writing signed by duly authorized
representatives of both parties.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 4
to be executed by their duly authorized representatives effective as of the date
first set forth above.


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"VENDOR" OR "LUCENT"                          "OWNER" OR "CRICKET"
LUCENT TECHNOLOGIES INC.,                     CRICKET COMMUNICATIONS, INC.,
a Delaware corporation                        a Delaware corporation

By: /s/ FRANK A. DELCORE                      By: /s/ S.D. HUTCHESON
    ----------------------------------            -----------------------------

Name: Frank A. DelCore                        Name: S.D. Hutcheson
      --------------------------------

Title: Director                               Title: Senior Vice President and
       -------------------------------                Chief Financial Officer

Date: 9/13/02                                 Date: September 13, 2002
      --------------------------------



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