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                                                                 EXHIBIT 10.19.4

                                AMENDMENT # 6 TO
                       SYSTEM EQUIPMENT PURCHASE AGREEMENT


        THIS AMENDMENT #6 TO SYSTEM EQUIPMENT PURCHASE AGREEMENT (this
"Amendment") is made effective as of February 5, 2001, by and between CRICKET
COMMUNICATIONS, INC., a Delaware corporation ("Owner"), and ERICSSON WIRELESS
COMMUNICATIONS INC., a Delaware corporation ("Vendor").


                                    RECITALS

        WHEREAS, Owner and Vendor entered into that certain System Equipment
Purchase Agreement dated as of September 20, 1999, as modified by Amendment #1
and Amendment #2 thereto, both of which are dated November 28, 2000, Amendment
#3 thereto, dated December 18, 2000, and Amendment #4 and Amendment #5 thereto,
both of which are dated December 27, 2000 (the "Contract"); and

        WHEREAS, Owner entered into that certain Credit Agreement dated as of
October 20, 2000, by and among Cricket Communications Holdings, Inc., Owner, the
lenders party thereto and Ericsson Credit AB, as administrative agent, as
modified by Amendment No. 1 thereto, dated as of the date hereof; and

        WHEREAS, Owner and Vendor wish to enter into this Amendment to provide
for the issuance of certain Purchase Orders by Owner to Vendor under the
Contract;

        NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, and intending to be legally bound, the parties
hereto agree as follows:


                                    AGREEMENT

1.      Interpretation.

        1.1 Capitalized terms not otherwise defined herein shall have the same
meanings as set forth in the Contract.

        1.2 The words "hereof", "herein", and "hereunder" and words of similar
import when used in this Amendment, refer to this Amendment as a whole and not
to any particular provision of the Amendment, and section and exhibit references
(if any) are to this Amendment unless otherwise specified or the context
otherwise requires.

        1.3 The meanings given to terms defined in this Amendment are equally
applicable to both the singular and plural forms of such terms.



[*] 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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2.      Amendment of Contract.

        2.1 Section 1.1 of the Contract is amended by adding the following
additional definition thereto in appropriate alphabetical order:

                        "Credit Agreement" shall mean that certain Credit
                Agreement dated as of October 20, 2000, by and among Cricket
                Communications Holdings, Inc., Owner, the lender parties thereto
                and Ericsson Credit AB, as administrative agent, as amended,
                modified or supplemented from time to time.

        2.2     Section 2.10 of the Contract is redesignated as Section 2.10(a)
                thereof.

        2.3     A new subsection 2.10(b) is added to the Contract to read as
                follows:

                        (b) The Credit Agreement originally provided for Loans
                to Owner in an aggregate principal amount at any date not to
                exceed [*] of the price of Products and Services purchased and
                paid on or before such date under this Contract, plus [*] (the
                "Initial Cap" with respect to such date), provided that at no
                given time could the maximum principal amount committed therein
                exceed $495,000,000. The Credit Agreement is now being amended
                so that, until December 31, 2001, Owner may borrow Loans in an
                aggregate principal amount at any date not to exceed [*] of the
                price of Products and Services purchased and paid on or before
                such date under this Contract, plus [*], up to the maximum
                principal amount of $495,000,000. In consideration of Ericsson
                Credit AB agreeing to that amendment, the Parties agree that, on
                or before any date on which Owner shall borrow any amount under
                the Credit Agreement, Owner shall have provided Vendor with
                irrevocable, unconditional purchase orders under this Contract
                for Specification compliant Products manufactured by Vendor, or
                manufactured by third parties for Vendor's offerings to
                customers generally and/or Services provided by Vendor (and not
                by third parties) that: (i) are delivered to Vendor between
                January 11, 2001 and the date of such borrowing, (ii) are for
                Products and/or Services to be deployed in markets other than
                Spokane, WA, Reno, NV, Boise, ID, and Salem, OR, and (iii) have
                an aggregate Purchase Price equal to a minimum of [***]. The
                delivery dates for all said Products and Services being ordered
                under said purchase orders shall be subject to the lead times
                provided for under this Contract and said delivery dates shall
                be for no later than [***]. (As used in this Section 2.10(b),
                the terms "Loans" and "Purchase Price" shall have the meanings
                set forth in the Credit Agreement.).



[*] 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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3.      Execution.

        3.1 This Amendment may be executed in any number of counterparts and by
different parties hereto in separate counterparts, each of which when so
executed shall be deemed to be an original and all of them taken together shall
constitute one and the same amendment.

        3.2 Delivery of an executed counterpart of a signature page to this
Amendment by telecopier shall be as effective as delivery of a manually executed
counterpart of this Amendment.

4. Full Force and Effect. Except as expressly modified in this Amendment, the
Contract shall remain unmodified and in full force and effect.

5. Interpretation. In the event of any conflict between the terms of this
Amendment and the Contract, the terms of this Amendment shall prevail with
respect to the subject matter herein.

6. Entirety of Amendment. This Amendment to the Contract together with Amendment
No.1 to the Credit Agreement shall supercede in its entirety that certain letter
agreement by and among the parties, Cricket Communications Holdings, Inc.,
Vendor and Ericsson Credit AB, dated January 11, 2001, regarding "Ericsson
Vendor Financing."

        IN WITNESS HEREOF, the parties hereto have caused this Amendment to be
executed by their duly authorized representatives effective as of the date first
set forth above.

                                            "OWNER"
                                            CRICKET COMMUNICATIONS, INC.,
                                            a Delaware corporation

                                            By: /s/ GLENN UMETSU
                                               ---------------------------------
                                            Name: Glenn Umetsu
                                                 -------------------------------
                                            Title: VP -- Engineering and Market
                                                   Launches
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                                            "VENDOR"
                                            ERICSSON WIRELESS COMMUNICATIONS
                                            INC., a Delaware corporation

                                            By: /s/ AKE PERSSON
                                               ---------------------------------
                                            Name: AKE PERSSON
                                                 -------------------------------
                                            Title: President
                                                  ------------------------------