Document:

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                                 EXHIBIT 10.3

                             AMENDMENT TO GUARANTY

     The Guaranty Agreement (the "Agreement") entered into as of the 20th day of
May, 1994, by and between DWAIN A. NEWMAN ("Guarantor") and NATIONAL HOME
CENTERS, INC., an Arkansas corporation (the "Company"), is hereby amended as
follows:

1.   As of September 24, 1999, the two Split Dollar Life Insurance Agreements
     are superseded by a single Split Dollar Life Insurance Agreement, and the
     Plans involving Metropolitan Life Insurance Policy No. 940450248A and John
     Hancock Mutual Life Insurance Company Policy No. 80081383 are both
     superseded by a single Plan involving Conseco Life Insurance Company Policy
     No. 1090545711.

2.   All other provisions of the original Guaranty Agreement remain in full
     force and effect.

     EXECUTED as of the 24th day of September, 1999, but signed the ____ day of
September, 1999.

                                   -----------------------------------
                                   DWAIN A. NEWMAN, Guarantor

                                       1<PAGE>

                                                                    EXHIBIT 4.1

THIS COMMON STOCK PURCHASE WARRANT HAS NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") OR UNDER ANY APPLICABLE LAW OR
REGULATION OF ANY STATE.  THIS COMMON STOCK WARRANT MAY NOT BE SOLD, OFFERED,
ASSIGNED OR TRANSFERRED UNLESS THE WARRANT IS REGISTERED UNDER THE SECURITIES
ACT AND APPLICABLE STATE SECURITIES LAWS, OR UNLESS SUCH OFFERS, SALES,
ASSIGNMENTS AND TRANSFERS ARE MADE PURSUANT TO THE AVAILABLE EXEMPTIONS FROM THE
REGISTRATION REQUIREMENTS OF THOSE LAWS.

                      ARDIS Telecom & Technologies, Inc.

                         COMMON STOCK PURCHASE WARRANT

                                                         DATED:  April 26, 1999

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Number of Common Shares:      20,000              Holder:   W. Thomas Rinehart
Purchase Price:               $0.45 per share               700 Freeling Drive
Expiration Date:              May 1, 2001                   Sarasota, FL  34242

             For identification only. The governing terms of this
                         Warrant are set forth below.
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     ARDIS Telecom & Technologies, Inc., a Delaware corporation (the "Company"),
hereby certifies that, for value received, W. Thomas Rinehart (the "Holder"), is
entitled, subject to the terms set forth below, to purchase from the Company at
any time or from time to time prior to May 1, 2001 (the "Exercise Period"), at
the Purchase Price hereinafter set forth, Twenty Thousand (20,000) fully paid
and nonassessable shares of Common Stock (as hereinafter defined) of the
Company.  The number and character of such shares of Common Stock and the
Purchase Price are subject to adjustment as provided herein.  This Warrant has
been delivered by the Company pursuant to the terms of the Consulting Agreement
between the Holder, the Company and RDST, Inc., a Texas corporation and wholly-
owned subsidiary of the Company.

     The purchase price per share of Common Stock issuable upon exercise of this
Warrant (the "Purchase Price") shall initially be $0.45; provided, however, that
the Purchase Price shall be adjusted from time to time as provided herein.

     As used herein the following terms, unless the context otherwise requires,
have the following respective meanings:

           (a)   The term "Company" shall mean ARDIS Telecom & Technologies,
     Inc. and any entity that shall succeed or assume the obligations of such
     corporation hereunder.

           (b)   The term "Common Stock" means the Company's common stock, .001
     par value per share.

           (c)   The term "Warrant Shares" means as of any date during the
     Exercise Period, that number of shares of Common Stock which shall be
     exercisable by the Holder hereof pursuant to the terms of this Warrant.

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COMMON STOCK PURCHASE WARRANT - Page 1
(ARDIS Telecom & Technologies, Inc.)
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     1.    Exercise of Warrant.

           1.1.  Method of Exercise. This Warrant may be exercised in whole or
     in part (but not as to a fractional share of Common Stock), at any time and
     from time to time during the Exercise Period for up to, but not more than,
     the number of Warrant Shares at such time, by the Holder hereof by delivery
     to the Company at its principal office of (i) a notice of exercise (a
     "Notice of Exercise") substantially in the form attached hereto as
     Exhibit A, (ii) evidence satisfactory to the Company of the authority of
     the person executing such Notice of Exercise, (iii) this Warrant, and (iv)
     payment of the Purchase Price multiplied by the number of shares of Common
     Stock for which this Warrant is being exercised (the "Exercise Price").
     Payment of the Exercise Price shall be made by check or bank draft payable
     to the order of the Company or by wire transfer to the account of the
     Company. The shares so purchased shall be deemed to be issued as of the
     close of business on the date on which the Company shall have received from
     the Holder payment in full of the Exercise Price and the other documents
     referred to herein (the "Exercise Date").

           1.2.  Regulation D Restrictions. The Holder hereof represents and
     warrants to the Company that it has acquired this Warrant and anticipates
     acquiring the shares of Common Stock issuable upon exercise of the Warrant
     solely for its own account for investment purposes and not with a view to
     or for distributing such securities unless such distribution has been
     registered with the Securities and Exchange Commission or an applicable
     exemption is available therefor. At the time this Warrant is exercised, the
     Company may require the Holder to state in the Notice of Exercise such
     representations concerning the Holder as are necessary or appropriate to
     assure compliance by the Holder with the Securities Act.

     2.    Delivery of Stock Certificates, etc., on Exercise. As soon as
practicable after the exercise of this Warrant, the Company will cause to be
issued in the name of and delivered to the Holder a certificate for the number
of fully paid and nonassessable shares of Common Stock to which the Holder shall
be entitled on such exercise, plus, in lieu of any fractional share to which the
Holder would otherwise be entitled, cash equal to such fraction multiplied by
the then applicable Purchase Price, together with any other stock or other
securities and property (including cash, where applicable) to which the Holder
is entitled upon such exercise pursuant to Section 1 or otherwise.

     3.    Adjustments on Certain Capital Transactions. On the occurrence of any
of the following events, the following adjustments to the rights granted under
this Warrant shall be made:

           3.1.  In case the number of outstanding shares of Common Stock of the
     Company shall be increased by way of a stock dividend, stock split,
     recapitalization, or other similar means, the number of unexercised shares
     of Common Stock covered by this Warrant shall be increased by the amount
     that a like number of shares of outstanding Common Stock shall have been
     increased as a result of such stock increase and the Purchase Price shall
     be adjusted by multiplying the Purchase Price in effect immediately prior
     to such stock increase by a fraction, the numerator of which shall be the
     number of unexercised shares covered by this Warrant immediately prior to
     such stock increase and

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COMMON STOCK PURCHASE WARRANT - Page 2
(ARDIS Telecom & Technologies, Inc.)
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     the denominator of which shall be the number of unexercised shares of
     Common Stock covered by this Warrant as adjusted for such stock increase.

           3.2.  In case the number of outstanding shares of Common Stock of the
     Company shall be reduced by recapitalization, reverse stock split or
     otherwise, the number of unexercised shares covered by this Warrant shall
     be reduced by the amount that a like number of shares of outstanding Common
     Stock shall have been reduced as a result of such stock reduction and the
     Purchase Price shall be adjusted by multiplying the Purchase Price in
     effect immediately prior to such stock reduction by a fraction, the
     numerator of which shall be the number of unexercised shares covered by
     this Warrant immediately prior to such stock reduction and the denominator
     of which shall be the number of unexercised shares covered by this Warrant
     as adjusted for such stock reduction.

           3.3.  In case the Company shall consolidate with or merge into
     another corporation, the holder of this Warrant will thereafter receive,
     upon the exercise thereof in accordance with the terms of this Warrant, the
     securities or property to which the holder of the number of shares of
     Common Stock then deliverable upon the exercise of this Warrant would have
     been entitled upon such consolidation or merger ("Other Securities") and
     the Company shall take such steps in connection with such consolidation or
     merger as may be necessary to assure that the provisions hereof shall
     thereafter be applicable, as nearly as reasonably may be, in relation to
     any securities or property thereafter deliverable upon the exercise of this
     Warrant.

     4.    Rights as a Shareholder. Holder shall not have any rights as a
shareholder of the Company with respect to the shares subject to this Warrant.

     5.    Securities Law Requirements. Neither this Warrant nor the Warrant
Shares have been registered under the Securities Act or any state securities or
blue sky laws. Accordingly, upon (a) any transfer of this Warrant, any
transferee of this Warrant or (b) the exercise of this Warrant in whole or in
part, and if the Warrant Shares have not been registered under the Securities
Act, Holder or any other person exercising this Warrant shall, as applicable,
represent and agree in writing satisfactory to the Company that Holder or such
other person (a) is acquiring the shares for the purpose of investment and not
with a view to distribution thereof, (b) knows the shares have not been
registered under the Securities Act or any state securities or blue sky laws,
(c) understands that he must bear the economic risk of said investment for an
indefinite period of time until the shares are registered under the Securities
Act and applicable state securities or blue sky laws or an exemption from such
registration is available, and (d) will not solicit any offer to sell or sell
all or any portion of the shares other than pursuant to an opinion of counsel
reasonably satisfactory to the Company.

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COMMON STOCK PURCHASE WARRANT - Page 3
(ARDIS Telecom & Technologies, Inc.)
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     6.    Reservation of Stock, etc. Issuable on Exercise of Warrant. The
Company will at all times reserve and keep available, solely for issuance and
delivery on the exercise of this Warrant, all shares of Common Stock (or Other
Securities) from time to time issuable on the exercise of this Warrant.

     7.    Replacement of Warrant. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of any such loss, theft or destruction of this
Warrant, on delivery of an indemnity agreement or security satisfactory in form
and amount to the Company or, in the case of any such mutilation, on surrender
and cancellation of this Warrant, the Company at its expense will execute and
deliver, in lieu thereof, a new warrant of like tenor.

     8.    Notices, etc. All notices and other communications hereunder shall be
personally delivered, telecopied or mailed by first class registered or
certified mail, postage prepaid, at such address of facsimile numbers as may
have been furnished to each party by the other in writing.

     9.    Miscellaneous. This Warrant and any term hereof may be changed,
waived, discharged or terminated only by an instrument in writing signed by the
party against which enforcement of such change, waiver, discharge or termination
is sought. This Warrant shall be construed and enforced in accordance with and
governed by the internal laws of the State of Texas. The headings in this
Warrant are for purposes of reference only, and shall not limit or otherwise
affect any of the terms hereof. The invalidity or unenforceability of any
provision hereof shall in no way affect the validity or enforceability of any
other provision.

                           [SIGNATURE PAGE FOLLOWS]

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COMMON STOCK PURCHASE WARRANT - Page 4
(ARDIS Telecom & Technologies, Inc.)
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     DATED as of April 26, 1999.

                                        ARDIS Telecom & Technologies, Inc.

                                        By:       /s/ Roger D. Bryant
                                            -----------------------------------
                                        Name:     Roger D. Bryant
                                              ---------------------------------
                                        Title:    President
                                               --------------------------------

                                        Address:  8100 Jetstar Drive, Suite 100
                                                  Irving, Texas  75063
                                                  Fax: (972) 929-1616

                                        HOLDER:
                                        ------

                                        /s/ W. Thomas Rinehart
                                        ---------------------------------------
                                        W. Thomas Rinehart

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COMMON STOCK PURCHASE WARRANT - Page 5
(ARDIS Telecom & Technologies, Inc.)
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                                   EXHIBIT A

                     FORM OF NOTICE OF EXERCISE - WARRANT
                     ------------------------------------

               (To be executed only upon exercise or conversion
                      of the Warrant in whole or in part)

To ARDIS Telecom & Technologies, Inc.

     The undersigned registered holder of the accompanying Warrant hereby
exercises such Warrant or portion thereof for, and purchases thereunder,
___________/1/ shares of Common Stock (as defined in such Warrant) and herewith
makes payment therefor of $__________ as of the date written below. The
undersigned requests that the certificates for such shares of Common Stock be
issued in the name of, and delivered to, _________________________________ whose
address is ___________________________________________________________________.

Dated:
        ----------------------------

                                        ---------------------------------------
                                        (Name must conform to name of holder as
                                        specified on the face of the Warrant)

                                        By:
                                           ------------------------------------
                                        Name:
                                             ----------------------------------
                                        Title:
                                              ---------------------------------

                                        Address of holder:

                                        ---------------------------------------
                                        ---------------------------------------
                                        ---------------------------------------

Date of exercise:
                 --------------------

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/1/  Insert the number of shares of Common Stock as to which the accompanying
Warrant is being exercised. In the case of a partial exercise, a new Warrant or
Warrants will be issued and delivered, representing the unexercised portion of
the accompanying Warrant, to the holder surrendering the same.

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