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                                                                 EXHIBIT 10.37

                   AMENDED AND RESTATED UNCONDITIONAL GUARANTY

      THIS AMENDED AND RESTATED UNCONDITIONAL GUARANTY (the "Guaranty") is made
as of April 23, 2004, by BRIGHTSTAR CORP., a Delaware corporation (the
"Guarantor"), in favor of MOTOROLA , INC., a Delaware corporation, in its
capacity as agent for itself and the other Motorola Parties (in such capacity,
"Motorola").

                             Preliminary Statements

      (a)   The Guarantor entered into an unconditional guaranty dated June 18,
2001 (the "Original Guaranty"), in favor of Motorola, Inc.

      (b)   The Original Guaranty was amended by an Omnibus Amendment made as of
May 24, 2002, by and among Motorola, Inc., the Guarantor and the other parties
thereto.

      (c)   The Guarantor desires to further amend the Original Guaranty and to
restate it in its entirety as so further amended and Motorola is willing to
allow such further amendment and restatement.

      NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Guarantor agrees to amend and restate the Original Guaranty in
its entirety as follows:

      1.    Definitions. All capitalized terms used but not defined in this
Guaranty have the meanings given in the Amended and Restated Payment Terms
Agreement, dated as of April 23, 2004, by and among Motorola, Inc. (in its
capacity as agent for itself and the other Motorola Parties), Brightstar Corp.
and the other persons and entities that are parties thereto (as the same may be
amended, restated, supplemented or otherwise modified from time to time, the
"Payment Terms Agreement").

      2.    Amendment and Restatement; Guaranties and Liens Unimpaired. This
Guaranty amends, restates and replaces the Original Guaranty in its entirety. It
is the intention and understanding of the parties that (a) this Guaranty shall
continue the obligations under the Original Guaranty (and any Brightstar
Obligations represented, guarantied or secured thereby) and shall not act as a
novation of the Original Guaranty (or any Brightstar Obligations represented,
guarantied or secured thereby), (b) all guaranties and all security interests,
pledges and other liens guarantying or securing the Original Guaranty (or any
Brightstar Obligations represented, guarantied or secured thereby) shall remain
in full force and effect and shall guarantee and secure this Guaranty (and all
Brightstar Obligations represented, guarantied or secured thereby), and (c) the
priority of all guaranties and all security interests, pledges and other liens
guarantying or securing any obligations under the Original Guaranty (or any
Brightstar Obligations represented, guarantied or secured thereby) shall not be
impaired by the execution, delivery or performance of this Guaranty.

      3.    Guaranty. The Guarantor hereby unconditionally guarantees the
punctual payment and performance when due, whether at stated maturity, by
acceleration or otherwise, of all of the Brightstar Obligations. The amount that
the Guarantor is obligated to pay hereunder is

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unlimited. Further, whether or not suit is brought by Motorola to acquire
possession of any collateral of the Guarantor or any Brightstar Party or to
enforce collection of any unpaid balance(s) under any of the Brightstar
Documents, the Guarantor expressly hereby agrees to pay all legal expenses and
the reasonable attorney's fees (including those relative to appellate
proceedings, if any) actually incurred by Motorola in enforcement of any of the
Brightstar Obligations or any of the Brightstar Documents against any of the
Brightstar Parties.

      4.    Other Documents. The Guarantor has made other representations and
warranties to Motorola and has entered into various other agreements with
Motorola including but not limited to those set forth in the Brightstar
Documents. The Guarantor acknowledges that the provisions of the Brightstar
Security Agreement under the heading "Bankruptcy" are incorporated herein by
reference and that each reference to the "Agreement" (either directly or as a
part of the Brightstar Documents) in the provisions of the Brightstar Security
Agreement under the heading "Bankruptcy" shall also be deemed to be a reference
to this Guaranty.

      5.    Unconditional Nature of Guaranty. This Guaranty is and shall remain
an unconditional and continuing guaranty of payment and not of collection, shall
remain in full force and effect irrespective of any interruption(s) in the
business or other dealings and relations of any of the Brightstar Parties with
any of the Motorola Parties and shall apply to and guarantee the due and
punctual payment of all Brightstar Obligations. To that end, the Guarantor
hereby expressly waives any right to require Motorola to bring any action
against any of the Brightstar Parties or any other person(s) or to require that
resort be had to any security or to any balance(s) of any deposit or other
account(s) or debt(s) or credit(s) on the books of any of the Motorola Parties
in favor of any of the Brightstar Parties or any other person(s). The Guarantor
acknowledges that its liabilities and obligations hereunder are primary rather
than secondary. To that end and without limiting the generality of the
foregoing, the Guarantor herewith expressly waives any rights it otherwise might
have had under provisions of the law of the State of Florida to require Motorola
to attempt to recover against any of the Brightstar Parties and/or to realize
upon any securities or collateral security which Motorola or any of the Motorola
Parties holds for the Brightstar Obligations. Notwithstanding the satisfaction
or performance of the Brightstar Obligations, the Guarantor's liability shall
continue to exist for so long as the satisfaction of the Brightstar Obligations
could be set aside or such Brightstar Obligations otherwise be reinstated under
bankruptcy, insolvency, fraudulent conveyance, debtor relief, or other similar
laws of any Federal, State of other competent jurisdiction.

      6.    Timeliness. TIME IS OF THE ESSENCE HEREOF.

      7.    Set-off. If any process is issued or ordered to be served upon any
of the Motorola Parties, seeking to seize any right and/or interest of the
Guarantor or any of the Brightstar Parties in any amounts owed by any of the
Motorola Parties, if any, the balance(s) owed shall immediately be deemed to
have been and shall be set-off against any and all Brightstar Obligations and/or
all obligations and liabilities of the Guarantor hereunder, as of the time of
the issuance of any such writ or process; whether or not the Guarantor, the
Brightstar Parties and/or any of the Motorola Parties shall then have been
served therewith.

      8.    Application of Payments. All moneys available to and/or received by
Motorola for application toward payment of (or reduction of) the Brightstar
Obligations may be applied by

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Motorola in such manner, and apportioned in such amount(s) and at such time(s),
as Motorola, in its sole discretion, may deem suitable or desirable.

      9.    Security Interest. As security for any and all liabilities of the
Guarantor hereunder now existing or hereinafter arising, or otherwise, the
Guarantor hereby grants Motorola a security interest in any and all moneys or
other property, i.e. goods and merchandise, as well as all documents relative
thereto; also, funds, investment securities, chooses in action and any and all
other forms of property, whether real, personal or mixed, and any right, title,
or interest of the Guarantor therein or thereto and/or the proceeds thereof,
which have been or may hereafter be left with any of the Motorola Parties (or
with any agent or other third party acting on behalf of any of the Motorola
Parties) by or for the account or credit of the Guarantor, including (without
limitation of the foregoing), any property in which the Guarantor may have any
interest. The Guarantor represents and warrants that all such property shall at
all times be free and clear of all Liens, other than Permitted Liens.

      10.   Perfection Irrelevant. The Guarantor agrees that its liability
hereunder shall not be diminished by any failure on the part of Motorola to
perfect (by filing, recording, or otherwise) any security interest(s) it may
have in any property securing this Guaranty and/or the Brightstar Obligations
secured hereby and hereunder.

      11.   Consents and Waivers. The Guarantor further hereby consents and
agrees that Motorola may at any time, or from time to time, in its sole
discretion: (i) extend or change the time of payment, and/or the manner, place
or terms of payment of any or all of the Brightstar Obligations; (ii) exchange,
release and/or surrender all or any of the collateral security, or any part(s)
thereof, by whomsoever deposited, which is or may hereafter be held by it in
connection with all or any of the Brightstar Obligations and/or any liabilities
or obligations of the Guarantor hereunder; (iii) sell or otherwise dispose of
an/or purchase all or any of such collateral at public or private sale, or to or
through any Investment Securities Broker, and after deducting all costs and
expenses of every kind for collection, preparation for sale, sale or delivery,
the net proceeds of any such sale(s) or other disposition may be applied by
Motorola upon all or any of the Brightstar Obligations; (iv) release any
endorser of the Brightstar Obligations or any guarantor thereof, with or without
consideration and without notice to or further consent from the Guarantor and
such release shall not in any way affect the liability of the undersigned; (v)
settle or compromise with any of the Brightstar Parties (and/or any other
person(s) liable thereon) any and all of the Brightstar Obligations (including
but not limited to, any insurance applicable to the Brightstar Obligations)
and/or subordinate the payment of all or any part of same, to the payment of any
other debts or claims, which may at any time(s) be due or owing to Motorola, any
of the Motorola Parties and/or any other person(s); (vi) alter, extend, change,
modify, release, waive or cancel any covenant, agreement, condition, obligation
or provision contained in any or all Brightstar Documents; all in such manner
and upon such terms as Motorola may deem proper and/or desirable, and without
notice to or further assent from the Guarantor, it being agreed that the
Guarantor shall be and remain bound upon this Guaranty, irrespective of the
existence, value or condition of any collateral; and notwithstanding any such
change, exchange, settlement, compromise, surrender, release, foreclosure, sale
or other disposition, application, renewal or extension and notwithstanding also
that the Brightstar Obligations may at any time(s) exceed the aggregate
principal sum hereinabove prescribed (if any such limiting sum appears).
Further, this Guaranty shall not be construed to impose any obligations on
Motorola or any of the Motorola

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Parties to extend or continue to permit extended payment terms or otherwise deal
with any of the Brightstar Parties at any time.

      12.   Deemed Authority. This Guaranty covers all Brightstar Obligations
purporting to be created or undertaken on behalf of any of the Brightstar
Parties by any officer, partner, manager or agent of such organizations, without
regard to the actual authority of any such officer, partner, manager or agent,
whether or not corporate resolutions, proper or otherwise, are given by any
Brightstar Party to Motorola or any Motorola Party, and/or whether or not such
purported organizations are legally chartered or organized.

      13.   Subrogation and Subordination. In consideration of Motorola's
permitting extended payment terms by the Brightstar Parties, which continued
right is subject to Motorola's sole discretion and subject to the terms of the
Payment Terms Agreement and the other Brightstar Documents, the Guarantor hereby
agrees:

            (a)   To subordinate, and by this Guaranty does subordinate, all
debts and other obligations now or hereafter owed by any of the Brightstar
Parties to the Guarantor to any and all debts of any of the Brightstar Parties
to any Motorola Party now or hereafter existing while this Guaranty is in
effect.

            (b)   Every note evidencing any part of the subordinated debt and
other obligations and every ledger page relating thereto will bear a legend,
which will indicate this subordination.

            (c)   Except to the extent permitted by the Payment Terms Agreement,
the Guarantor will not request or accept payment of any principal of, interest
on or security for, any part of the subordinated debt or other obligations (and
will not claim any offset or other reduction of the Guarantor's obligations
hereunder because of any such subordinated debt or other obligation), and if all
or part of it should be paid to the Guarantor, through error or otherwise, the
Guarantor will immediately forward every such payment to Motorola in the form
received, properly endorsed to the order of Motorola, to apply on any debt or
other obligations then owing to any of the Motorola Parties by any of the
Brightstar Parties. This subordination shall continue in full force and effect
as long as this Guaranty is in effect.

            (d)   The Guarantor further agrees that it will not assert any right
to which it may be or become entitled, whether by subrogation, contribution or
otherwise against any of the Brightstar Parties or any of their respective
properties, by reason of the performance of the undersigned of its obligations
under this Guaranty, except after payment in full of all amounts (including cost
and expenses) which may become payable in respect of or under the Brightstar
Obligations.

      14.   Successors and Assigns. This Guaranty shall be binding upon the
Guarantor and the successors and assigns of the Guarantor, and it shall inure to
the benefit of, and be enforceable by, Motorola and its successors, transferees
and assigns.

      15.   Additional Definitions. Further all terms or expressions contained
herein that are defined in the Uniform Commercial Code of the State of Florida
shall be the same meaning herein as in said Code.

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      16.   No Waiver. No waiver by Motorola of any default(s) by the Guarantor
or any of the Brightstar Parties shall operate as a waiver of any other default
or of the same default on a future occasion. Further, use of the masculine or
neuter pronoun herein shall include the masculine, feminine and neuter, and also
the plural. The term "the Guarantor" as used herein, shall mean the "the
Guarantors and each of them." Motorola, or any other holder hereof, may correct
patent errors in this Guaranty.

      17.   Waiver of Formalities. The Guarantor hereby waives (i) notice of
acceptance of this Guaranty; (ii) notice(s) of extensions of credit and/or
continuations of credit extensions to any of the Brightstar Parties by any
Motorola Party; (iii) notice(s) of entering into and engaging in business
transactions and/or contractual relationships and any other dealings between any
of the Brightstar Parties and any Motorola Party, (iv) presentment and/or demand
for payment of any of the Brightstar Obligations; (v) protest or notice of
dishonor or default to the Guarantor or to any other person with respect to any
of the Brightstar Obligations; (vi) any demand for payment under this Guaranty;
and (vii) to the extent such benefit can be waived, the benefit of other laws
purporting to limit the enforcement of an obligation of the Guarantor.

      18.   Usury. Anything contained herein to the contrary notwithstanding, if
for any reason the effective rate of interest on any of the Brightstar
Obligations should exceed the maximum lawful rate, the effective rate of such
Brightstar Obligations shall be deemed reduced to and shall be such maximum
lawful rate, and any sums of interest which have been collected in excess of
such maximum lawful rate shall be applied as credit against the unpaid principal
balance due hereunder.

      19.   Independent Counsel. The Guarantor hereby acknowledges that Motorola
has suggested that the Guarantor and the Brightstar Parties obtain independent
legal counsel to represent their interests in the transaction evidenced hereby
and the Brightstar Documents, and the Guarantor and the Brightstar Parties have
elected to retain independent counsel to represent them in those transactions.

      20.   Marshalling. The Guarantor waives any right or claim of right to
cause a marshalling of any assets of any of the Brightstar Parties or the assets
of any other party now or hereafter held as security for the Brightstar
Obligations, and waives the benefit of any statute of limitations affecting the
liability of the Guarantor hereunder, to the extent permitted by law.

      21.   Remedies on Default. Upon the occurrence of any Default or Event of
Default, all of the Brightstar Obligations shall immediately be due and payable
without notice. Further, Motorola shall then have all of the rights and remedies
granted hereunder, all of the rights and remedies of a secured party and/or
holder-in-due-course under the Uniform Commercial Code as adopted and other
Laws of the State of Florida.

      22.   Receipt of Brightstar Documents. The Guarantor hereby acknowledges
and agrees to having received and reviewed a copy of all of the Brightstar
Documents executed to date and is familiar with the various representations,
warranties, covenants and obligations with respect to the Guarantor contained in
the Brightstar Documents. The Guarantor hereby acknowledges that failure to
timely comply with each and every of the covenants and obligations contained in
the Brightstar Documents that pertain or relate to the Guarantor, including with

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limitation, the covenants regarding delivery of financial statements of the
Guarantor to Motorola, will result in an event of default thereunder entitling
Motorola to the rights and remedies contained therein, including without
limitation, acceleration of the Brightstar Obligations.

      23.   Preservation and Limitation of Remedies. Motorola shall have the
right to proceed in any court of proper jurisdiction or by self-help to
exercise or prosecute the following remedies, as applicable: (i) all rights to
foreclose against any real or personal property or other security by exercising
a power of sale granted under the Brightstar Documents or under applicable law
or by judicial foreclosure and sale, including a proceeding to confirm the sale;
(ii) all rights of self-help including peaceful occupation of real property and
collection of rents, set-off, and peaceful possession of personal property;
(iii) obtaining provisional or ancillary remedies including injunctive relief,
sequestration, garnishment, attachment, appointment of receiver and filing an
involuntary bankruptcy proceeding; and (iv) when applicable, a judgment by
confession of judgment.

      24.   Limits on Damages. The Guarantor and Motorola agree that they shall
not have a remedy of punitive or exemplary damages against the other in any
dispute and hereby waive any right or claim to punitive or exemplary damages
they have now or which may arise in the future in connection with any dispute.

      25.   Notices. Any notice, demand or other communications required to or
permitted to be given or made hereunder in writing, shall be deemed given or
made when (a) delivered in person; (b) five (5) days after such communication is
posted in the mails; or (c) one (1) day after such communication is sent by a
nationally recognized overnight courier service. Such communications shall be
addressed as follows:

            If to Motorola to:       Motorola, Inc
                                     798 International Parkway
                                     Sunrise, Florida 33325
                                     Attn: PCS Latin America Director of Finance

            With a copy to:          Shook, Hardy & Bacon L.L.P.
                                     Miami Center, Suite 2400
                                     201 South Biscayne Boulevard
                                     Miami, Florida 33131-4332
                                     Attn:  John M. Barkett, Esq.

            If to the Guarantor to:  Brightstar Corp.
                                     2010 N. W. 84th Avenue
                                     Miami, Florida 33122
                                     Attn:  Raul M. Claure

            With a copy to:          Kirkpatrick & Lockhart LLP
                                     Miami Center, 20th Floor
                                     201 South Biscayne Boulevard
                                     Miami, Florida 33131
                                     Attn:  Clayton E. Parker, Esq.

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      or at such other address or addresses as the party addressed may from time
to time designate in writing.

      26.   Governing Law. This Guaranty will be deemed made in and governed by
the laws of the State of Florida, without regard to laws regarding conflicts of
law.

      27.   Severability. If any term or provision of this Guaranty should be
declared invalid by a court of competent jurisdiction, the remaining terms and
provisions will be unimpaired and the invalid term or provision will be replaced
by such valid term or provision as comes closest to the intention underlying
the invalid term or provision.

      28.   WAIVER OF JURY TRIAL. THE GUARANTOR AND MOTOROLA HEREBY KNOWINGLY,
VOLUNTARILY AND INTENTIONALLY WAIVE THE RIGHT EACH MAY HAVE TO A TRIAL BY JURY
IN RESPECT OF ANY LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER OR IN
CONNECTION WITH THIS GUARANTY OR ANY OTHER AGREEMENT BETWEEN ANY OF THE
BRIGHTSTAR PARTIES, ON ONE HAND, AND ANY MOTOROLA PARTY ON THE OTHER HAND, OR
ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER VERBAL OR
WRITTEN) OR ACTIONS OF EACH PARTY. THIS PROVISION IS A MATERIAL INDUCEMENT FOR
THE GUARANTOR AND MOTOROLA ENTERING INTO THIS AGREEMENT. THE PROVISIONS OF THIS
ARTICLE HAVE BEEN FULLY NEGOTIATED BY THE PARTIES HERETO AND THESE PROVISIONS
SHALL BE SUBJECT TO NO EXCEPTIONS. NEITHER THE GUARANTOR NOR MOTOROLA HAS IN ANY
WAY AGREED WITH OR REPRESENTED TO ANY OTHER PARTY THAT THE PROVISIONS OF THIS
ARTICLE WILL NOT BE ENFORCED IN ALL INSTANCES. NEITHER THE GUARANTY NOR MOTOROLA
SHALL SEEK TO CONSOLIDATE ANY SUCH ACTION, IN WHICH A JURY TRIAL HAS BEEN
WAIVED, WITH ANY OTHER ACTION IN WHICH A JURY TRIAL HAS NOT BEEN OR CANNOT BE
WAIVED.

      29.   Waiver of Plea or Jurisdictions or Venue. Because the Guarantor and
Motorola each have significant interest in consistent interpretation of this
Guaranty, the Guarantor designates Miami, Florida as the sole forum for
resolution of any dispute arising hereunder. The Guarantor hereby waives any
plea of jurisdiction or venue as not having a place of business in Miami-Dade
County, Florida, and hereby specifically authorizes any action brought upon the
enforcement of this Guaranty by Motorola to be instituted and prosecuted in
either the Circuit Court of Miami-Dade County, Florida, or in the United States
District Court for the Southern District of Florida, at the election of
Motorola. The Guarantor further agrees that a final judgment in any action or
proceeding will be conclusive and may be enforced against it in any other
jurisdiction or in any other manner provided by law.

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      30.   Miscellaneous. This Guaranty may be validly executed and delivered
by fax or other electronic transmission and in one or more counterpart signature
pages. This Guaranty shall be construed without presumption for or against the
drafter of all or any part hereof. Section headings are for convenience of
reference only and shall not limit the scope of any Section. All factual
recitals and other matters set forth in the Preliminary Statements to this
Guaranty shall constitute a part of this Guaranty.

                          [Signature page(s) to follow]

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      IN WITNESS WHEREOF, the Guarantor has executed and delivered this Guaranty
as of the date first above written.

                                     BRIGHTSTAR CORP.

                                     BY: /s/ R. Marcelo Claure
                                        ----------------------------------------
                                     NAME: R. Marcelo Claure
                                     TITLE: President

                                     ACCEPTED:

                                     MOTOROLA, INC.

State of New York   )                By: /s/ Dennis J. Strand
                      SS.                ---------------------------------------
County of New York  )                Name: DENNIS J. STRAND
                                     Title: CFO - PCS

      The foregoing instrument was acknowledged before me this 23 day of April,
2004, by Marcelo Claure, who in his capacity as President of BRIGHTSTAR CORP., a
Delaware Corporation, and who is personally known to me or has produced driver's
license as identification.

                                     /s/ Delores Taylor
                                     ------------------------------------------
                                     NOTARY PUBLIC
                                     NAME OF NOTARY PRINTED: ___________________
                                                    (NOTARY SEAL)

My Commission Expires:

______________________                       [DELORES TAYLOR STAMP]

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