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                                                                   EXHIBIT 4.2


THE REPRESENTATIVE'S WARRANTS EVIDENCED AND REPRESENTED BY THIS CERTIFICATE (THE
"REPRESENTATIVE'S WARRANTS") AND THE SECURITIES ISSUABLE UPON EXERCISE HEREOF
(THE "WARRANT SHARES") HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, PURSUANT TO A REGISTRATION STATEMENT FILED WITH THE SECURITIES AND
EXCHANGE COMMISSION AND WITH THE SECURITIES ADMINISTRATORS OF CERTAIN STATES
UNDER THE SECURITIES ("BLUE SKY") LAWS OF SUCH STATES. HOWEVER, NEITHER THE
REPRESENTATIVE'S WARRANTS NOR SUCH WARRANT SHARES MAY BE SOLD, TRANSFERRED,
PLEDGED, OR HYPOTHECATED EXCEPT PURSUANT TO (I) A POST-EFFECTIVE AMENDMENT TO
SUCH REGISTRATION STATEMENT, (II) A SEPARATE REGISTRATION STATEMENT UNDER SUCH
ACT, OR (III) AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND UNDER THE
APPLICABLE BLUE SKY LAWS , AS ESTABLISHED TO THE REASONABLE SATISFACTION OF THE
COMPANY.

THIS REPRESENTATIVE'S WARRANT AND THE WARRANT SHARES MAY NOT BE SOLD,
TRANSFERRED OR ASSIGNED EXCEPT AS OTHERWISE PROVIDED HEREIN AND THE HOLDER OF
THIS REPRESENTATIVE'S WARRANT, BY ITS ACCEPTANCE HEREOF, AGREES THAT IT WILL NOT
SELL, TRANSFER OR ASSIGN THIS REPRESENTATIVE'S WARRANT OR THE WARRANT SHARES
EXCEPT AS OTHERWISE PROVIDED HEREIN.


                         PENTASTAR COMMUNICATIONS, INC.

            Representative's Warrant for the Purchase of Common Stock

No. UW-001                                    125,000 Representative's Warrants

     THIS CERTIFIES that, for receipt in hand of $10 and other value received,
SCHNEIDER SECURITIES, INC. (the "Holder"), is entitled to subscribe for and
purchase from PENTASTAR COMMUNICATIONS, INC., a Delaware corporation (the
"Company"), upon the terms and conditions set forth herein, at any time, or from
time to time, after October 26,1999, and before 5:00 p.m. Mountain time on
October 26, 2004 (the "Exercise Period"), 125,000 shares of Common Stock (the
"Warrant Shares"), at a price of $12.00 per Warrant Share (the "Exercise
Price"), or 120% of the offering price of Common Stock to be sold by the Company
in a public offering (the "Public Offering") at or prior to the date hereof.

     The term the "Holder" as used herein shall include any transferee to whom
this Representative's Warrant has been transferred in accordance with the above.
As used herein the term "this Representative's Warrant" shall mean and include
this Representative's Warrant and any Representative's Warrant or
Representative's Warrants hereafter issued as a consequence of the exercise or
transfer of this Representative's Warrant in whole or in part, and the term
"Common Stock" shall mean and include the Company's Common Stock with ordinary
voting power, which class at the date hereof is publicly traded.

     1. This Representative's Warrant may not be sold, transferred, assigned,
pledged or hypothecated until October 26, 2000 (12 months from the Effective
Date of the Registration Statement on which it is initially registered) except
that it may be transferred, in whole or in part, (i) to one or more officers or
partners of the Holder (or the officers or partners of any such partner); (ii)
to a member of the underwriting syndicate and/or its officers or partners; or
(iii) by operation of law. After October 26, 2000, this Representative's Warrant
may be sold, transferred, assigned or hypothecated in accordance with applicable
law and the terms of this Representative's Warrant.



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     2.   a. This Representative's Warrant may be exercised during the Exercise
     Period as to the whole or any lesser number of Warrant Shares, by the
     surrender of this Representative's Warrant (with the election attached
     hereto duly executed) to the Company at its office at 1522 Blake Street,
     Denver, Colorado, or such other place as is designated in writing by the
     Company, together with a certified or bank cashier's check payable to the
     order of the Company in an amount equal to the Exercise Price multiplied by
     the number of Warrant Shares for which this Representative's Warrant is
     being exercised.


          b. Upon written request of the Holder, and in lieu of payment for the
     Warrant Shares by check in accordance with paragraph 2(a) hereof, the
     Holder may exercise the Representative's Warrant (or any portion thereof)
     for and receive the number of Warrant Shares equal to a fraction, the
     numerator of which equals (i) the amount by which the Current Market Price
     of the Common Stock for the ten (10) trading days preceding the date of
     exercise exceeds the Exercise Price per Share, multiplied by (ii) the
     number of Warrant Shares to be purchased; the denominator of which equals
     the Current Market Price.

          c. For the purposes of any computation under this Representative's
     Warrant, the "Current Market Price" at any date shall be the closing price
     of the Common Stock on the business day next preceding the event requiring
     an adjustment hereunder. If the principal trading market for such
     securities is an exchange, the closing price shall be the reported last
     sale price on such exchange on such day provided if trading of such Common
     Stock is listed on any consolidated tape, the closing price shall be the
     reported last sale price set forth on such consolidated tape. If the
     principal trading market for such securities is the over-the-counter
     market, the closing price shall be the last reported sale price on such
     date as set forth by The Nasdaq Stock Market, Inc., or, if the security is
     not quoted on such market, the average of the closing bid and asked prices
     as set forth in the National Quotation Bureau pink sheets or the Electronic
     Bulletin Board System for such day. Notwithstanding the foregoing, if there
     is no reported last sale price or average closing bid and asked prices, as
     the case may be, on a date prior to the event requiring an adjustment
     hereunder, then the current market price shall be determined as of the
     latest date prior to such day for which such last sale price or average
     closing bid and asked prices are available.


     3. Upon each exercise of this Representative's Warrant, the Holder shall be
deemed to be the holder of record of the Warrant Shares issuable upon such
exercise, notwithstanding that the transfer books of the Company shall then be
closed or certificates representing such Warrant Shares shall not then have been
actually delivered to the Holder. As soon as practicable after each such
exercise of this Representative's Warrant, the Company shall issue and deliver
to the Holder a certificate or certificates for the Warrant Shares

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issuable upon such exercise, registered in the name of the Holder or its
designee. If this Representative's Warrant should be exercised in part only, the
Company shall, upon surrender of this Representative's Warrant for cancellation,
execute and deliver a new Representative's Warrant evidencing the right of the
Holder to purchase the balance of the Warrant Shares (or portions thereof)
subject to purchase hereunder.



     4. The Representative's Warrants shall be registered in a Representative's
Warrant Register as they are issued. The Company shall be entitled to treat the
registered holder of any Representative's Warrant on the Representative's
Warrant Register as the owner in fact thereof for all purposes and shall not be
bound to recognize any equitable or other claim to or interest in such
Representative's Warrant on the part of any other person. The Representative's
Warrants shall be transferable only on the books of the Company upon delivery
thereof duly endorsed by the Holder or by its duly authorized attorney or
representative, or accompanied by proper evidence of succession, assignment or
authority to transfer. In all cases of transfer by an attorney, executor,
administrator, guardian or other legal representative, duly authenticated
evidence of his or its authority shall be produced. Upon any registration of
transfer, the Company shall deliver a new Representative's Warrant or
Representative's Warrants to the person entitled thereto. The Representative's
Warrants may be exchanged, at the option of the Holder thereof, for another
Representative's Warrant, or other Representative's Warrants of different
denominations, of like tenor and representing in the aggregate the right to
purchase a like number of Warrant Shares (or portions thereof) upon surrender to
the Company or its duly authorized agent. Notwithstanding the foregoing, the
Company shall have no obligation to cause the Representative's Warrants to be
transferred on its books to any person if, in the opinion of counsel to the
Company, such transfer does not comply with the provisions of the Securities Act
of 1933, as amended (the "Act"), or applicable state blue sky laws and the rules
and regulations thereunder.


     5. The Company shall at all times reserve and keep available out of its
authorized and unissued Common Stock, solely for the purpose of providing for
the exercise of this Representative's Warrant, such number of shares of Common
Stock as shall, from time to time, be sufficient therefor. The Company covenants
that all Warrant Shares issuable upon exercise of this Representative's Warrant
shall be validly issued, fully paid, nonassessable, and free of preemptive
rights.


     6.   a. If the Company shall at any time subdivide its outstanding Common
     Stock by recapitalization, reclassification or split-up thereof, the number
     of Warrant Shares subject to this Representative's Warrant immediately
     prior to such subdivision shall be proportionately increased, and if the
     Company shall at any time combine the outstanding Common Stock by
     recapitalization, reclassification or combination thereof, the number of
     Warrant Shares subject to this Representative's Warrant immediately prior
     to such combination shall be proportionately decreased.


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     Any corresponding adjustment to the Exercise Price shall become effective
     at the close of business on the record date for such subdivision or
     combination.

          b. If the Company after the date hereof shall distribute to the
     holders of its Common Stock any securities or other assets (other than a
     distribution of Common Stock or a cash distribution made as a dividend
     payable out of earnings or out of any earned surplus legally available for
     dividends under the laws of the jurisdiction of incorporation of the
     Company), the Board of Directors shall be required to make such equitable
     adjustment in the Exercise Price in effect immediately prior to the record
     date of such distribution as may be necessary to preserve the rights
     substantially proportionate to those enjoyed hereunder by the Holder
     immediately prior to such distribution. Any such adjustment made in good
     faith by the Board of Directors shall be final and binding upon the Holder
     and shall become effective as of the record date for such distribution.

          c. No adjustment in the number of Warrant Shares subject to this
     Representative's Warrant shall be required unless such adjustment would
     require an increase or decrease in such number of Warrant Shares of at
     least 1% of the then adjusted number of Warrant Shares issuable upon
     exercise of this Representative's Warrant, provided, however, that any
     adjustments which by reason of the foregoing are not required at the time
     to be made shall be carried forward and taken into account and included in
     determining the amount of any subsequent adjustment; and provided further,
     however, that in case the Company shall at any time subdivide or combine
     the outstanding Common Stock or issue any additional Common Stock as a
     dividend, said percentage shall forthwith be proportionately increased in
     the case of a combination or decreased in the case of a subdivision or
     dividend of Common Stock so as to appropriately reflect the same. If the
     Company shall make a record of the holders of its Common Stock for the
     purpose of entitling them to receive any dividend or distribution and
     legally abandon its plan to pay or deliver such dividend or distribution
     then no adjustment in the number of Warrant Shares subject to this
     Representative's Warrant shall be required by reason of the making of such
     record.

          d. Whenever the number of Warrant Shares purchasable upon the exercise
     of this Representative's Warrant is adjusted as provided herein, the
     Exercise Price shall be adjusted (to the nearest one tenth of a cent) by
     respectively multiplying such Exercise Price immediately prior to such
     adjustment by a fraction, the numerator of which shall be the number of
     Warrant Shares purchasable upon the exercise of this Representative's
     Warrant immediately prior to such adjustment, and the denominator of which
     shall be the number of Warrant Shares purchasable immediately thereafter.


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          e. In case of any reclassification of the outstanding Common Stock
     (other than a change covered by (a) hereof or which solely affects the par
     value of such Common Stock) or in the case of any merger or consolidation
     of the Company with or into another corporation (other than a consolidation
     or merger in which the Company is the continuing corporation and which does
     not result in any reclassification or capital reorganization of the
     outstanding Common Stock), or in the case of any sale or conveyance to
     another corporation of the property of the Company as an entirety or
     substantially as an entirety in connection with which the Company is
     dissolved, the Holder of this Representative's Warrant shall have the right
     thereafter (until the expiration of the right of exercise of this
     Representative's Warrant) to receive upon the exercise hereof, for the same
     aggregate Exercise Price payable hereunder immediately prior to such event,
     the kind and amount of shares of stock or other securities or property
     receivable upon such reclassification, capital reorganization, merger or
     consolidation, or upon the dissolution following any sale or other
     transfer, by a holder of the number of Warrant Shares obtainable upon the
     exercise of this Representative's Warrant immediately prior to such event;
     and if any reclassification also results in a change in Common Stock
     covered by (a) above, then such adjustment shall be made pursuant to both
     this paragraph (e) and paragraph (a). The provisions of this paragraph (e)
     shall similarly apply to successive re- classifications, or capital
     reorganizations, mergers or consolidations, sales or other transfers.


          f. i. Upon occurrence of each event requiring an adjustment of the
          Exercise Price and of the number of Warrant Shares purchasable upon
          exercise of this Representative's Warrant in accordance with, and as
          required by, the terms hereof, the Company shall forthwith compute the
          adjusted Exercise Price and the adjusted number of Warrant Shares
          purchasable at such adjusted Exercise Price by reason of such event in
          accordance herewith. The Company shall give to each Holder of the
          Representative's Warrants a copy of such computation which shall be
          conclusive and shall be binding upon such Holders unless contested by
          Holders by written notice to the Company within thirty (30) days after
          receipt thereof.

               ii. In case the Company after the date hereof shall propose to
          take any action requiring adjustment of the number of Warrant Shares
          pursuant to paragraph 6(a), (b) or (e), or the liquidation,
          dissolution or winding up of the Company, then in each such case, the
          Company shall make the computation described above and if an
          adjustment to the Exercise Price is required, the Company shall notify
          the Holders of the Representative's Warrants of such proposed action,
          which shall specify the record date for any such action or if no
          record date is established with respect thereto, the date on which
          such action shall occur or


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          commence, or the date of participation therein by the holders of
          Common Stock if any such date is to be fixed, and shall also set forth
          such facts with respect thereto as shall be reasonably necessary to
          indicate the effect of such action on the Exercise Price and the
          number, or kind, or class of shares or other securities or property
          obtainable upon exercise of this Representative's Warrant after giving
          effect to any adjustment which will be required as a result of such
          action. Such notice shall be given at least fifteen (15) days prior to
          the record date for determining holders of the Common Stock for
          purposes of any such action, and in the case of any action for which a
          record date is not established then such notice shall be mailed at
          least fifteen (15) days prior to the taking of such proposed action.

               iii. Failure to file any certificate or notice or to give any
          notice, or any defect in any certificate or notice, shall not effect
          the legality or validity of the adjustment in the Exercise Price or in
          the number, or kind, or class of shares or other securities or
          property obtainable upon exercise of the Representative's Warrants or
          of any transaction giving rise thereto.


          g. The Company shall not be required to issue fractional Warrant
     Shares upon any exercise of the Representative's Warrants. As to any final
     fraction of a Share which the Holder of a Representative's Warrant would
     otherwise be entitled to purchase upon such exercise, the Company shall pay
     a cash adjustment in respect of such final fraction in an amount equal to
     the same fraction of the market price of a share of such stock on the
     business day preceding the day of exercise. The Holder of a
     Representative's Warrant, by his acceptance of a Representative's Warrant,
     expressly waives any right to receive any fractional Warrant Shares.

          h. Regardless of any adjustments pursuant to this section in the
     Exercise Price or in the number, or kind, or class of shares or other
     securities or other property obtainable upon exercise of a Representative's
     Warrant, a Representative's Warrant may continue to express the Exercise
     Price and the number of Warrant Shares obtainable upon exercise at the same
     price and number of Warrant Shares as are stated herein.

          i. The number of Warrant Shares, the Exercise Price and all other
     terms and provisions of the Company's agreement with the Holder of this
     Representative's Warrant shall be determined exclusively pursuant to the
     provisions hereof.

          j. The above provisions of this section 6 shall similarly apply to
     successive transactions which require adjustments.

          k. Notwithstanding any other language to the contrary herein, (i) the
     anti-dilution terms of this Representative's Warrant will not be enforced
     so as to provide the Holder the right to


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     receive, or for the accrual of, cash dividends prior to the exercise of
     this Representative's Warrant, and (ii) the anti-dilution terms of this
     Representative's Warrant will not be enforced in such a manner as to
     provide the Holder with disproportionate rights, privileges and economic
     benefits not provided to purchasers of the Common Stock in the Public
     Offering.


     7. The issuance of any Warrant Shares or other securities upon the exercise
of this Representative's Warrant and the delivery of certificates or other
instruments representing such securities, or other securities, shall be made
without charge to the Holder for any tax or other charge in respect of such
issuance. The Company shall not, however, be required to pay any tax which may
be payable in respect of any transfer involved in the issue and delivery of any
certificate in a name other than that of the Holder and the Company shall not be
required to issue or deliver any such certificate unless and until the person or
persons requesting the issue thereof shall have paid to the Company the amount
of such tax or shall have established to the satisfaction of the Company that
such tax has been paid.


     8. a. If, at any time after October 26, 1999 (the Effective Date of the
     Registration Statement), and ending October 26, 2006 (seven years after the
     Effective Date of the Registration Statement), the Company shall file a
     registration statement (other than on Form S-4, Form S-8, or any successor
     form) with the Securities and Exchange Commission (the "Commission") while
     Warrant Shares are available for purchase upon exercise of this
     Representative's Warrant or while any Warrant Shares (collectively, the
     Representative's Warrants and the underlying Warrant Shares, the
     "Representative's Securities") are outstanding, the Company shall, on two
     occasions only, give the Holder and all the then holders of such
     Representative's Securities at least 30 days prior written notice of the
     filing of such registration statement. If requested by the Holder or by any
     such holder in writing within 10 days after receipt of any such notice, the
     Company shall, at the Company's sole expense (other than the fees and
     disbursements of counsel for the Holder or such holder and the underwriting
     discounts, if any, payable in respect of the securities sold by the Holder
     or any such holder), register or qualify the Representative's Securities of
     the Holder or any such holders who shall have made such request
     concurrently with the registration of such other securities, all to the
     extent requisite to permit the public offering and sale of the
     Representative's Securities requested to be registered. Notwithstanding the
     foregoing, if the managing underwriter of any such offering shall advise
     the Company in writing that, in its opinion, the distribution of all or a
     portion of the Representative's Securities requested to be included in the
     registration concurrently with the securities being registered by the
     Company would materially adversely affect the distribution of such
     securities by the Company for its own account, then the Holder or any such
     holder who shall have requested registration of his or its Representative's
     Securities shall delay the offering and sale of


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     such Representative's Securities (or the portions thereof so designated by
     such managing underwriter) for such period, not to exceed 90 days, as the
     managing underwriter shall request, provided that no such delay shall be
     required as to any Representative's Securities if any securities of the
     Company are included in such registration statement for the account of any
     person other than the Company and the Holder unless the securities included
     in such registration statement for such other person shall have been
     reduced pro rata to the reduction of the Representative's Securities which
     were requested to be included in such registration. The Company shall not
     be required to complete any registration commenced under this paragraph
     8(a) if it determines for any reason not to proceed with the offering of
     securities it proposed to register.


          b. If at any time after October 26, 1999 (the Effective Date of the
     Registration Statement), and before October 26, 2004 (five years after the
     Effective Date of the Registration Statement), the Company shall receive a
     written request from holders of Representative's Securities who, in the
     aggregate, own (or upon exercise of all Representatives Warrants will own)
     a majority of the total number of Warrant Shares, the Company shall, as
     promptly as practicable, prepare and file with the Commission a
     registration statement sufficient to permit the public offering and sale of
     the Representative's Securities, and will use its best efforts through its
     officers, directors, auditors and counsel to cause such registration
     statement to become effective as promptly as practicable; provided,
     however, that the Company shall only be obligated to file and obtain
     effectiveness of one such registration statement. All expenses incurred in
     connection with such registration (other than the fees and disbursements of
     counsel for the Holder or such holders and underwriting discounts, if any,
     payable in respect of the Representative's Securities sold by the Holder or
     any such holder) shall be borne by the Company. Notwithstanding the
     foregoing, if the Company shall furnish to each of the Holders a
     certificated signed by the Chief Executive Officer of the Company stating
     that in the good faith judgment of the Board of Director of the Company it
     would be significantly disadvantageous to the Company and its shareholders
     for such a registration statement to be filed, the Company shall have the
     right to defer such filing for a period of not more than 90 days after
     receipt of the request to effect such a registration; provided, however,
     that the Company may not utilize this right more than once; and provided,
     further, that the holders who made such written request to effect such
     registration, may, at any time in writing during this 90-day deferral,
     withdraw such request for such registration and thereby preserve the right
     provided in this paragraph 6b to again request such registration; and
     provided further, however, that during such 90-day period and for a period
     of 30 days after the effectiveness of such registration statement, the
     Company will not file any registration statement(s) relating to an offering
     or sale of shares of its Common Stock by the Company or any selling
     shareholder other than the Holders.

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          c. In the event of a registration pursuant to the provisions of this
     paragraph 8, the Company shall use its best efforts to cause the
     Representative's Securities so registered to be registered or qualified for
     sale under the securities or blue sky laws of such jurisdictions as the
     Holder or such holders may reasonably request; provided, however, that the
     Company shall not be required to qualify to do business in any state by
     reason of this paragraph 8(c) in which it is not otherwise required to
     qualify to do business and provided further, that the Company has no
     obligation to qualify the Representative's Securities where such
     qualification would cause any unreasonable delay or expenditure by the
     Company.

          d. The Holders agree not to effect any public sale or public
     distribution of equity securities of the Company or any securities
     exercisable for such securities, during the seven days prior to and the
     60-day period beginning on the effective date of any underwritten
     registration in which Representative's Securities are included (except as
     part of such underwritten registration) unless the managers managing the
     registered public offering otherwise agree.

          e. The Company shall keep effective any registration or qualification
     contemplated by this paragraph 8 and shall from time to time amend or
     supplement each applicable registration statement, preliminary prospectus,
     final prospectus, application, document and communication for such period
     of time as shall be required to permit the Holder or such holders to
     complete the offer and sale of the Representative's Securities covered
     thereby. The Company shall in no event be required to keep any such
     registration or qualification in effect for a period in excess of nine
     months from the date on which the Holder and such holders are first free to
     sell such Representative's Securities; provided, however, that if the
     Company is required to keep any such registration or qualification in
     effect beyond such period with respect to securities other than the
     Representative's Securities, the Company shall keep such registration or
     qualification in effect as it relates to the Representative's Securities
     for so long as such registration or qualification remains or is required to
     remain in effect in respect of such other securities.

          f. In the event of a registration pursuant to the provisions of this
     paragraph 8, the Company shall furnish to the Holder and to each such
     holder such reasonable number of copies of the registration statement and
     of each amendment and supplement thereto (in each case, including all
     exhibits), such reasonable number of copies of each prospectus contained in
     such registration statement and each supplement or amendment thereto
     (including each preliminary prospectus), all of which shall conform to the
     requirements of the Act and the rules and regulations thereunder, and


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     such other documents as the Holder or such holders may reasonably request
     in order to facilitate the disposition of the Representative's Securities
     included in such registration.

          g. In the event of a registration pursuant to the provisions of this
     paragraph 8, the Company shall furnish the Holder and each holder of any
     Representative's Securities so registered with an opinion of its counsel to
     the effect that (i) the registration statement has become effective under
     the Act and no order suspending the effectiveness of the registration
     statement, preventing or suspending the use of the registration statement,
     any preliminary prospectus, any final prospectus, or any amendment or
     supplement thereto has been issued, nor to such counsel's actual knowledge
     has the Securities and Exchange Commission or any securities or blue sky
     authority of any jurisdiction instituted or threatened to institute any
     proceedings with respect to such an order and (ii) the registration
     statement and each prospectus forming a part thereof (including each
     preliminary prospectus), and any amendment or supplement thereto, complies
     as to form with the Act and the rules and regulations thereunder. Such
     counsel shall also provide a Blue Sky Memorandum setting forth the
     jurisdictions in which the Representative's Securities have been registered
     or qualified for sale pursuant to the provisions of paragraph 8(c).

          h. The Company agrees that until all the Representative's Securities
     have been sold under a registration statement or pursuant to Rule 144 under
     the Act, it shall keep current in filing all reports, statements and other
     materials required to be filed with the Commission to permit holders of the
     Representative's Securities to sell such securities under Rule 144.

          i. The Holder and any holders who propose to register their
     Representative's Securities under the Act shall execute and deliver to the
     Company a selling stockholder questionnaire on a form to be provided by the
     Company. Prior to filing any registration statement, or any amendments or
     supplements thereto, which includes any Representative's Securities, the
     Company will furnish to counsel for each Holder or other holder who has
     included Representative's Securities in such registration statement copies
     of all documents proposed to be filed, which documents will be subject to
     the timely review of such counsel. Each Holder or other holder shall be
     responsible for all fees and expenses of its own counsel. The Company shall
     allow each such Holder or other holder to conduct any desired due diligence
     in connection with such review. Each Holder and such other holders agree to
     provide all such information and materials and take all such action as may
     be reasonably required in order to permit the Company to comply with all
     applicable requirements of the Commission and to obtain any desired
     acceleration of the effective date of such registration statement.


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          j. The Company shall not be required by the terms hereof to file a
     Registration Statement if, in the opinion of counsel to the holders of the
     Representative's Warrants and Warrant Shares and counsel for the Company
     (or, should they not agree, in the opinion of another counsel experienced
     in securities law matters acceptable to counsel for the holders of
     Representative's Warrants and Warrant Shares and the Company), the proposed
     public offering or other transfer as to which such Registration Statement
     is requested to be filed is exempt from applicable federal and state
     securities laws, rules, regulations and would result in unaffiliated
     purchasers or transferees obtaining securities that are not "restricted
     securities" as that term is defined in Rule 144 under the Act.

     9. a. Subject to the conditions set forth below, the Company agrees to
     indemnify and hold harmless the Holder, any holder of any of the
     Representative's Securities, their officers, directors, partners,
     employees, agents and counsel, and each person, if any, who controls any
     such person within the meaning of Section 15 of the Act or Section 20(a) of
     the Securities Exchange Act of 1934, as amended (the "Exchange Act"), from
     and against any and all loss, liability, charge, claim, damage and expense
     whatsoever (which shall include, for all purposes of this Section 9, but
     not be limited to, attorneys' fees and any and all expense whatsoever
     incurred in investigating, preparing or defending against any litigation,
     commenced or threatened, or any claim whatsoever, and any and all amounts
     paid in settlement of any claim or litigation), as and when incurred,
     arising out of, based upon, or in connection with (i) any untrue statement
     or alleged untrue statement of a material fact contained (A) in any
     registration statement, preliminary prospectus or final prospectus (as from
     time to time amended and supplemented), or any amendment or supplement
     thereto, or (B) in any application or other document or communication (in
     this Section 9 collectively called an "application") executed by or on
     behalf of the Company or based upon written information furnished by or on
     behalf of the Company filed in any jurisdiction in order to register or
     qualify any of the Representative's Securities under the securities or blue
     sky laws thereof or filed with the Commission or any securities exchange;
     or any omission or alleged omission to state a material fact required to be
     stated therein or necessary to make the statements therein not misleading,
     unless such statement or omission was made in reliance upon and in
     conformity with written information furnished to the Company with respect
     to the Holder or any holder of any of the Representative's Securities by or
     on behalf of such person expressly for inclusion in any registration
     statement, preliminary prospectus, or final prospectus, or any amendment or
     supplement thereto, or in any application, as the case may be, or (ii) any
     breach of any representation, warranty, covenant or agreement of the
     Company


                                       11
<PAGE>   12
contained in this Representative's Warrant. The foregoing agreement to indemnify
shall be in addition to any liability the Company may otherwise have, including
liabilities arising under this Representative's Warrant.

          If any action is brought against the Holder or any holder of any of
the Representative's Securities or any of its officers, directors, partners,
employees, agents or counsel, or any controlling persons of such person (an
"indemnified party") in respect of which indemnity may be sought against the
Company pursuant to the foregoing paragraph, such indemnified party or parties
shall promptly notify the Company in writing of the institution of such action
(but the failure so to notify shall not relieve the Company from any liability
it may otherwise have to Holder or any holder of any of the Representative's
Securities) and the Company shall promptly assume the defense of such action,
including the employment of counsel (reasonably satisfactory to such indemnified
party or parties) and payment of expenses. Such indemnified party or parties
shall have the right to employ its or their own counsel in any such case, but
the fees and expenses of such counsel shall be at the expense of such
indemnified party or parties unless the employment of such counsel shall have
been authorized in writing by the Company in connection with the defense of such
action or the Company shall not have promptly employed counsel reasonably
satisfactory to such indemnified party or parties to have charge of the defense
of such action or such indemnified party or parties shall have reasonably
concluded that there may be one or more legal defenses available to it or them
or to other indemnified parties which are different from or additional to those
available to the Company, in any of which events such fees and expenses shall be
borne by the Company and the Company shall not have the right to direct the
defense of such action on behalf of the indemnified party or parties. Anything
in this paragraph to the contrary notwithstanding, the Company shall not be
liable for any settlement of any such claim or action effected without its
written consent.

          b. The Holder and each holder agrees to indemnify and hold harmless
     the Company, each director of the Company, each officer of the Company who
     shall have signed any registration statement covering the Representative's
     Securities held by the Holder and each holder and each other person, if
     any, who controls the Company within the meaning of Section 15 of the Act
     or Section 20(a) of the Exchange Act, and each underwriter of an
     underwritten offering, to the same extent as the foregoing indemnity from
     the Company to the Holder and each holder in paragraph 9(a), but only with
     respect to statements or omissions, if any, made in any registration
     statement, preliminary prospectus, or final prospectus (as from time to
     time amended and supplemented), or any amendment or supplement thereto, or
     in any application, in reliance upon and in conformity with written
     information furnished to the Company with respect to the Holder and each
     holder by or on


                                       12
<PAGE>   13

     behalf of the Holder and each holder expressly for inclusion in any such
     registration statement, preliminary prospectus, or final prospectus, or any
     amendment or supplement thereto, or in any application, as the case may be.
     If any action shall be brought against the Company or any other person so
     indemnified based on any such registration statement, preliminary
     prospectus, or final prospectus, or any amendment or supplement thereto, or
     in any application, and in respect of which indemnity may be sought against
     the Holder and each holder pursuant to this paragraph 9(b), the Holder and
     each holder shall have the rights and duties given to the Company, and the
     Company and each other person so indemnified shall have the rights and
     duties given to the indemnified parties, by the provisions of paragraph
     9(a).

          c. To provide for just and equitable contribution, if (i) an
     indemnified party makes a claim for indemnification pursuant to paragraph
     9(a) or 9(b) (subject to the limitations thereof) but it is found in a
     final judicial determination, not subject to further appeal, that such
     indemnification may not be enforced in such case, even though this
     Agreement expressly provides for indemnification in such case, or (ii) any
     indemnified or indemnifying party seeks contribution under the Act, the
     Exchange Act or otherwise because the indemnification provided for in this
     Section 9 is for any reason held to be unenforceable by the Company and the
     Holder and any holder, then the Company (including for this purpose any
     contribution made by or on behalf of (i) any director of the Company, (ii)
     any officer of the Company who signed any such registration statement and
     (iii) any controlling person of the Company), as one entity, and the Holder
     and any holder of any of the Representative's Securities included in such
     registration in the aggregate (including for this purpose any contribution
     by or on behalf of the Holder or any holder), as a second entity, shall
     contribute to the losses, liabilities, claims, damages and expenses
     whatsoever to which any of them may be subject, on the basis of relevant
     equitable considerations such as the relative fault of the Company and the
     Holder or any such holder in connection with the facts which resulted in
     such losses, liabilities, claims, damages and expenses. The relative fault,
     in the case of an untrue statement, alleged untrue statement, omission or
     alleged omission, shall be determined by, among other things, whether such
     statement, alleged statement, omission or alleged omission relates to
     information supplied by the Company, by the Holder or by any holder of
     Representative's Securities included in such registration, and the parties'
     relative intent, knowledge, access to information and opportunity to
     correct or prevent such statement, alleged statement, omission or alleged
     omission. The Company and the Holder agree that it would be unjust and
     inequitable if the respective obligations of the Company and the Holder for
     contribution were determined by pro rata or per


                                       13
<PAGE>   14

     capita allocation of the aggregate losses, liabilities, claims, damages and
     expenses (even if the Holder and the other indemnified parties were treated
     as one entity for such purpose) or by any other method of allocation that
     does not reflect the equitable considerations referred to in this paragraph
     9(c). No person guilty of a fraudulent misrepresentation (within the
     meaning of Section 11(f) of the Act) shall be entitled to contribution from
     any person who is not guilty of such fraudulent misrepresentation. For
     purposes of this paragraph 9(c), each person, if any, who controls the
     Holder or any holder of any of the Representative's Securities within the
     meaning of Section 15 of the Act or Section 20(a) of the Exchange Act and
     each officer, director, partner, employee, agent and counsel of each such
     person, shall have the same rights to contribution as such person and each
     person, if any, who controls the Company within the meaning of Section 15
     of the Act or Section 20(a) of the Exchange Act, each officer of the
     Company who shall have signed any such registration statement, and each
     director of the Company shall have the same rights to contribution as the
     Company, subject in each case to the provisions of this paragraph 9(c).
     Anything in this paragraph 9(c) to the contrary notwithstanding, no party
     shall be liable for contribution with respect to the settlement of any
     claim or action effected without its written consent. This paragraph 9(c)
     is intended to supersede any right to contribution under the Act, the
     Exchange Act or otherwise.


     10. Unless the Representative's Securities have been registered or an
exemption from such registration is available, the Warrant Shares issued upon
exercise of the Representative's Warrants shall be subject to a stop transfer
order and the certificate or certificates evidencing any such Warrant Shares
shall bear the following legend:

     THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
     NOR HAVE THEY BEEN REGISTERED UNDER THE SECURITIES ("BLUE SKY") LAWS OF ANY
     STATE. THESE SECURITIES MAY NOT BE SOLD, TRANSFERRED, PLEDGED, OR
     HYPOTHECATED UNLESS THEY HAVE FIRST BEEN REGISTERED UNDER THE SECURITIES
     ACT OF 1933 AND UNDER THE APPLICABLE STATE SECURITIES ("BLUE SKY") LAWS OR
     UNLESS THE AVAILABILITY OF AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT
     AND LAWS IS ESTABLISHED TO THE SATISFACTION OF THE COMPANY, WHICH MAY
     NECESSITATE A WRITTEN OPINION OF SELLER'S COUNSEL SATISFACTORY TO COMPANY
     COUNSEL.

     11. Upon receipt of evidence satisfactory to the Company of the loss,
theft, destruction or mutilation of any Representative's Warrant (and upon
surrender of any Representative's Warrant if mutilated), and upon reimbursement
of the Company's reasonable incidental expenses, the Company shall execute and
deliver to the Holder thereof a new Representative's Warrant of like date, tenor
and denomination.

     12. The Holder of any Representative's Warrant shall not have, solely on
account of such status, any rights of a stockholder of the Company, either at
law or in equity, or to any notice of meetings of stockholders or of any other
proceedings of the Company, except as provided in this Representative's Warrant.



                                       14
<PAGE>   15

     13. This Representative's Warrant shall be construed in accordance with the
laws of the State of Colorado, without giving effect to conflict of laws.


Dated: October 29, 1999

                                          PENTASTAR COMMUNICATIONS, INC.


                                          By: /s/ Craig J. Zoellner
                                             ----------------------------------
[SEAL]                                        Craig J. Zoellner, Vice President























                                       15
<PAGE>   16










                               FORM OF ASSIGNMENT


(To be executed by the registered holder if such holder desires to transfer the
attached Representative's Warrant.)

     FOR VALUE RECEIVED, ___________________________________ hereby sells,
assigns and transfers unto ________________________ Representative's Warrants to
purchase __________ shares of Common Stock of PentaStar Communications, Inc.
(the "Company"), together with all right, title and interest therein, and does
hereby irrevocably constitute and appoint ____________________________ attorney
to transfer such Representative's Warrants on the books of the Company, with
full power of substitution.

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



Signature:
          ---------------------------------------

Signature Guaranteed:








                                     NOTICE

     The signature on the foregoing Assignment must correspond to the name as
written upon the face of this Representative's Warrant in every particular,
without alteration or enlargement or any change whatsoever. Signature(s) must be
guaranteed by an eligible guarantor institution which is a participant in a
Securities Transfer Association recognized program.








                                       16
<PAGE>   17



                              ELECTION TO EXERCISE

             (To be executed by the holder if such holder desires to
                 exercise the attached Representative's Warrant)

     The undersigned hereby exercises his or its rights to subscribe for
__________ shares of Common Stock covered by the within Representative's Warrant
(each as defined in the within Representative's Warrant) and tenders payment
herewith in the amount of $__________ in accordance with the terms thereof, and
requests that certificates for such Warrants be issued in the name of, and
delivered to:


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

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

--------------------------------------------------------------------------------
                   (Print Name, Address and Social Security or
                           Tax Identification Number)

and, if such number of Warrants (or portions thereof) shall not be all the
Warrants covered by the within Representative's Warrant, that a new
Representative's Warrant for the balance of the Representative's Warrants (or
portions thereof) covered by the within Representative's Warrant be registered
in the name of, and delivered to, the undersigned at the address stated below.

Name:
    ----------------------------------------------------------------------------
                                     (Print)

Address:
       -------------------------------------------------------------------------


         (Signature)

Dated:                                               Signature Guaranteed:



                                     NOTICE

         The signature on the foregoing Assignment must correspond to the name
as written upon the face of this Representative's Warrant in every particular,
without alteration or enlargement or any change whatsoever. Signature(s) must be
guaranteed by an eligible guarantor institution which is a participant in a
Securities Transfer Association recognized program.






                                       17