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                                                                     EXHIBIT 4.3

                               IWC SERVICES, INC.
                         COMMON STOCK PURCHASE WARRANT
                              DATED MARCH 19, 1997
                     EXERCISABLE AT ANY TIME AT OR PRIOR TO
              3:30 P.M. CENTRAL STANDARD TIME ON DECEMBER 31, 2000
            TO PURCHASE THE NUMBER OF SHARES DETERMINED IN SECTION 1

THESE SECURITIES (THE "SECURITIES") HAVE BEEN (1) ACQUIRED FOR INVESTMENT; (II)
ISSUED AND SOLD IN RELIANCE UPON THE EXEMPTION FROM REGISTRATION UNDER THE
SECURITIES LAWS OF VARIOUS STATES; AND (III) ISSUED AND SOLD IN RELIANCE UPON
THE EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933 (THE "ACT")
PROVIDED BY SECTION 4(2) OF THE 1933 ACT.  THE SECURITIES CANNOT BE OFFERED FOR
SALE, SOLD OR TRANSFERRED OTHER THAN PURSUANT TO (A) AN EFFECTIVE REGISTRATION
UNDER THE ACT OR ANY TRANSACTION WHICH IS OTHERWISE IN COMPLIANCE WITH THE ACT;
AND (B) EVIDENCE SATISFACTORY TO THE ISSUER OF COMPLIANCE WITH THE APPLICABLE
SECURITIES LAWS OF ANY OTHER JURISDICTION.  THE ISSUER SHALL BE ENTITLED TO RELY
UPON AN OPINION OF COUNSEL SATISFACTORY TO IT WITH RESPECT TO COMPLIANCE WITH
THE ABOVE LAWS.

     This Common Stock Warrant ("Warrant") is issued as of the date set forth
above by IWC Services, Inc., a Texas corporation (the "Company"), to           
        or registered assigns (the "Holder").  This Warrant is part of a series
of Common Stock Warrants ("Warrants") issued in connection with the offer and
sale by the Company of up to 5,000 investment units ("Units") each of which
consists of a Warrant and a 12% Senior Subordinated Note (individually a "Note"
and collectively the "Notes") in the principal amount of $1,000 ($5,000,000 in
the aggregate) to the purchasers thereof (collectively the "Holders").

                                  WITNESSETH:

     1.    ISSUANCE OF WARRANT: TERM.  In consideration for the purchase
contemporaneously herewith of one or more 12% Senior Subordinated Note (the
"Notes") and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company hereby grants to the
Holder, subject to the provisions hereinafter set forth, the right to purchase
that number of shares of common stock, $.0l per share ("Common Stock"), of the
Company (the shares of Common Stock issuable upon exercise of this Warrant are
hereinafter referred to as the "Shares") determined by dividing the principal
amount of the Notes purchased by the Holder by the Exercise Price, as defined in
Section 2 hereof.  If the maturity date of the Notes is extended as provided in
Section 2 thereof, the Holder shall be granted an additional Warrant to purchase
that number of shares of Common Stock equal to 50% of the number of shares of
Common Stock purchasable under this Warrant.  This Warrant shall be exercisable
by the Holder at any time during the period ending at 3:30 p.m. Central Standard
Time on December 31, 2000 (the "Expiration Date").

     2.  EXERCISE PRICE. The exercise price (the "Exercise Price") per share for
the Shares that may be purchased pursuant to the terms of this Warrant shall be
either (i) one-half of the per share offering price for Common Stock sold by the
Company in an underwritten initial public offering, or (ii) one-half of the
average closing bid price of the Common Stock of the Company during the 90-day
period commencing 60 days after the closing of a business combination
transaction involving the Company and a publicly-held corporation whose shares
are traded in the over-the-counter market or on an established securities
exchange.  If the Company does not complete an initial public offering or
business combination transaction prior to the Expiration Date, the Exercise
Price per share for the Shares that may be purchased pursuant to the terms of
this Warrant shall be $2.00, which has been arbitrarily determined by the
Company and is not based on any established criteria for determining the value
of common stock.

     3.  EXERCISE OF WARRANTS.

          (A) EXERCISE PROCEDURES. Prior to the Expiration Date, this Warrant
          may be exercised at any time,

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          from time to time, by the Holder hereof, subject to the conditions set
          forth herein, by (i) delivering to the Company the written notice on
          the Form of Election to purchase attached hereto as Exhibit "A,"
          specifying the number of Shares that the Holder has elected to
          purchase, at the following address: 2800 Post Oak Boulevard, Suite
          6300, Houston, Texas, 77056 ("Company Office"), or such other address
          as the Company shall designate by written notice to the Holder, (ii)
          surrendering this Warrant to the Company, and (iii) delivering to the
          Company payment (in the manner set forth in Section 3(b) hereof) of
          the aggregate Exercise Price for the Shares to be purchased.  The date
          of the exercise of the purchase of any Shares to be purchased pursuant
          to this Warrant shall be deemed to be the date of receipt by the
          Company of the Form of Exercise duly completed and signed by the
          Holder, this Warrant and the appropriate aggregate Exercise Price.

          (B) PAYMENT OF EXERCISE PRICE; EXPENSES. The aggregate Exercise Price
          for the Shares to be purchased pursuant to the exercise of this
          Warrant shall be paid to the Company at the Company Office in cash, by
          wire transfer or by certified or official bank check.  The Company
          shall pay all expenses, taxes and other charges payable in connection
          with the preparation, execution and delivery of stock certificates
          pursuant to this Section 3, except that, in the case of stock
          certificates that have been registered in a name or names other than
          the names of the registered holder of this Warrant, funds sufficient
          to pay all stock transfer taxes which shall be payable upon the
          execution and delivery of such stock certificate or certificates,
          shall be paid by the registered holder hereto to the Company at the
          time of delivering this Warrant to the Company as mentioned above.

          (C) EXERCISE OF FEWER THAN ALL WARRANTS. If the Holder exercises this
          Warrant with respect to fewer than all of the Shares that may be
          purchased hereunder, then upon surrender of this Warrant at the
          Company Office by the registered Holder hereof in person or by
          attorney and the Form of Exercise duly authorized in writing, this
          Warrant will be exchanged for a similar Warrant, representing the
          right to purchase the remaining number of Shares subject to purchase
          hereunder.

          (D) DENOMINATIONS OF WARRANTS. This Warrant may be exchanged for new
          Warrants in different denominations at the option of the Holder by the
          surrender of this Warrant to the Company at the Company Office
          accompanied by written instructions setting forth the denominations of
          the new Warrants.

          (E) FRACTIONAL SHARES. No fractional shares of Common Stock will be
          issued upon the exercise of this Warrant, but in lieu thereof, a cash
          payment will be made to the Holder in an amount equal to any
          fractional share resulting from the calculation of the number of
          Shares to be purchased in accordance with the provisions in Section 1
          hereof multiplied by the Exercise Price determined in Section 2
          hereof.

     4.  ANTI-DILUTION PROTECTION.  The applicable Exercise Price per share
determined in Section 2 hereof and the number of Shares issuable upon exercise
of this Warrant determined in Section I hereof are subject to weighted average
adjustment from time to time upon the occurrence hereafter of certain
transactions by the Company, including dividends of stock or other securities or
property, stock splits, reverse stock splits, subdivisions, combinations,
recapitalizations, reorganizations, reclassifications, consolidations, mergers
or sales of properties and assets and dissolution (collectively,
"Reorganization").  In the event that the outstanding Common Stock of the
Company is at any time increased or decreased solely by reason of a
Reorganization, appropriate adjustments in the number and kind of such
securities then subject to this Warrant shall be made effective as of the date
of such occurrence so that the interest of the Holder upon exercise will be the
same as it would have been had such Holder owned the underlying securities
immediately prior to the occurrence of such event.  Such adjustment shall be
made successively whenever any Reorganization shall occur.  Not withstanding the
foregoing, no adjustment shall be required under this Section 4 until the
cumulative adjustments result in a dilution to the Holder of 5% or more.

     5.  TRANSFERABILITY.  The Warrants are separate and detachable securities,
transferable on the books of the Company at the Company Office by the registered
Holder hereof in person or by attorney duly authorized in writing, upon

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surrender of this Warrant to the Company for transfer.  Upon any such transfer,
a new Warrant to purchase a like number of Shares will be issued to the
transferee or transferees in exchange for this Warrant.  Upon receipt by the
Company of evidence reasonably satisfactory to it of the loss, theft,
destruction or mutilation of this Warrant, and, in case of loss, theft or
destruction, of an agreement of indemnity (without security therefor, and upon
surrender and cancellation of this Warrant, if mutilated), the Company will make
and deliver a new Warrant of like tenor, in lieu of this Warrant.  This Warrant
shall be promptly canceled by the Company upon the surrender hereof in
connection with any exchange, transfer or replacement. The Company shall pay all
expenses, taxes (other than stock transfer taxes) and other charges payable in
connection with the preparation, execution and delivery of this Warrant pursuant
to this Section.

     6.  HOLDER NOT A SHAREHOLDER.  No Holder of this Warrant shall, solely by
reason of being a Holder hereof, possess any right or privilege as a shareholder
of the Company, including without limitation, the right to vote or receive
dividends or be deemed for any purpose the holder of Common Stock or of any
other securities of the Company which may at any time be issuable on the
exercise hereof, until the Holder shall have exercised all or any  part of this
Warrant in accordance with the provisions set forth in Section 3 hereof.
Nothing contained herein shall be construed to confer upon the Holder, as such,
any of the rights of a shareholder of the Company or any right to vote upon any
matter submitted to shareholders at any meeting thereof, or to give or withhold
consent to any corporate action (whether upon any recapitalization, issue of
stock, reclassification of stock, change of par value, consolidation, merger,
conveyance, or otherwise) or, to receive notice of the meetings, until the
Warrant shall have been exercised as provided in Section 3 hereof.

     7.  COVENANTS AND CONDITIONS.  The provisions of this Warrant are subject
to the following covenants and conditions:

          (A) RESTRICTED SHARES. Neither this Warrant nor the Shares have been
          registered under the Act or the securities laws of any state (the
          "Blue Sky Laws").  By purchasing a Note and receiving this Warrant,
          the Holder hereof acknowledges that the Holder is acquiring this
          Warrant for investment purposes only, for his own account and not with
          a view to the distribution or resale of this Warrant without an
          effective registration for this Warrant under the Act and applicable
          Blue Sky Laws or an opinion of counsel reasonably satisfactory to the
          Company and its counsel that registration is not required under the
          Act or any applicable Blue Sky Laws.  The Shares issued upon exercise
          of this Warrant shall be restricted securities under the Act and
          applicable Blue Sky Laws, and the certificates representing the Shares
          shall bear a restrictive legend in substantially the same form as set
          forth on the cover page of this Warrant.

          Other legends as required under federal or state laws may be placed on
          the certificates evidencing any Shares purchased hereunder.  The
          Holder hereof agrees to execute such other documents and instruments
          as counsel for the Company reasonably deems necessary to effect the
          compliance of the issuance of this Warrant and any Shares issued upon
          exercise hereof with applicable federal and state securities laws.

          (B) RESERVATION OF SHARES. The Company covenants and agrees that the
          Shares to be issued upon the exercise of this Warrant shall, upon
          issuance and payment therefor in accordance with the terms hereof be
          legally and validly authorized, issued and outstanding, fully paid and
          nonassessable and free from preemptive rights.  The Company shall at
          all times reserve and keep available for issuance upon the exercise of
          this Warrant such number of authorized but unissued shares of Common
          Stock as will be sufficient to permit the exercise in full of  this
          Warrant and all other outstanding Warrants, taking into account for
          this purpose, any adjustments to the Shares purchasable under this
          Warrant as provided under Section 4 hereof.

          (C) AFFIRMATIVE AND RESTRICTED COVENANTS. The Company will at all
          times take such action in good faith asmay be necessary or appropriate
          in order to preserve the rights of the Holder.  The Company will not,
          by amendment of its certificate of incorporation, enter into any
          reorganization, transfer of assets, consolidation, merger, issue or
          sale of securities or otherwise avoid or take any action which would
          have the effect of avoiding the observance or performance of any of
          the terms to be observed or performed hereunder by the Company, but
          will at all times in good faith assist in carrying out all of the
          provisions

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          of this Warrant and in taking all such action as may be necessary or
          appropriate in order to protect the rights of the holders of this
          Warrant against dilution or other impairment.

          (D) FINANCIAL INFORMATION. So long as this Warrant or any part hereof
          remains outstanding, the Company shall furnish to the Holder: (i)
          unaudited, quarterly financial statements of the Company within forty-
          five (45) days after the end of each fiscal quarter; (ii) financial
          statements of the Company for each fiscal year within ninety (90) days
          after the end of the fiscal year, audited by a national accounting
          firm; and (iii) such other financial information of the Company as the
          Holder may reasonably request in writing, provided that such other
          financial information is prepared by the Company in the ordinary
          course.

     8.   REGISTRATION RIGHTS.

          (A) DEMAND REGISTRATION. The Company hereby agrees that upon the
          written request of a Holder or Holders of 50% or more of the aggregate
          number of Shares, which have been or could be issued or are issuable
          upon exercise of the Warrants, it will use its best efforts in
          accordance with the terms of this Section 8 to effect the registration
          under the Act of any Shares purchased pursuant to the terms of this
          Warrant; provided, however, that such request shall not be made until
          180 days after (i) the effective date of the Company's initial public
          offering, or (ii) the closing of a business combination transaction
          involving the Company and a publicly-held corporation whose shares are
          traded in the over-the-counter market or on an established securities
          exchange.  Such registration is herein sometimes referred to as the
          "Demand Registration." In connection with such Demand Registration,
          the Company will give written notice (a "Notice of Registration") to
          all of the Holders, of its intent to effect the Demand Registration
          under the Act of the Shares.  The Holders shall then provide the
          Company, within 15 days after the giving of the Notice of
          Registration, a written response which shall specify the number of
          Shares to be registered and the intended method of disposition
          thereof.  The Company shall not be required to effect more than one
          Demand Registration under this Section 8. It is understood and agreed
          that the Company's obligation to register the Shares hereunder may be
          fulfilled by either a Company-sponsored "shelf" registration or
          through an underwritten public offering and that if participation in
          either one of such types of registration is offered to the Holders,
          and that if a Holder shall be offered the ability to, and shall
          decline to participate in such Demand Registration, such offer and
          declination shall be deemed to constitute the registration rights
          granted hereunder with respect to the Shares subject thereto.

          (B) REGISTRATION STATEMENT FORM. The Demand Registration shall be on
          such appropriate registration form promulgated by the Commission as
          shall be selected by the Company, and shall permit the disposition of
          the Shares covered thereby in accordance with the intended method or
          methods specified by the Holders in their request for such
          registration.

          (C) REGISTRATION EXPENSES. The Company will pay all Registration
          Expenses incurred in connection with the Demand Registration.

          (D) RIGHT TO INCLUDE SHARES IN REGISTRATION.  The Company may include
          in the registration statement related to the Demand Registration
          securities on its own behalf The amount of securities that the Company
          may include in the registration statement relating to such Demand
          Registration on its own behalf shall be determined at the Company's
          sole discretion, taking into consideration all contractual
          registration rights then outstanding to all parties.

          (E) DELAY OF COMPANY'S REGISTRATION OBLIGATIONS. Notwithstanding the
          foregoing, the Company may postpone taking action with respect to the
          Demand Registration for a reasonable period if, in the good faith
          opinion of the Company's Board of Directors, effecting the
          registration would adversely affect a material financing, acquisition,
          disposition of assets or stock, merger or other comparable transaction
          or would require the Company to make public disclosure of information,
          the public disclosure of which would have a materially  adverse effect
          upon the Company, provided that the Company shall not delay

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          such action pursuant to this sentence more than once in any 6- month
          period.

          (F) TERMINATION OF RIGHTS. The registration rights granted hereunder
          shall terminate with respect to Shares that become eligible for resale
          under Rule 144, as in effect at the time, or any other applicable
          exemption for the registration requirements of the Act.

     9.  REGISTRATION PROCEDURES.  If and whenever the Company is required to
use its best efforts to effect the Demand Registration of any Shares under the
Act pursuant to Section 8, the Company will use its best efforts to effect the
Demand Registration and sale of such Shares in accordance with the intended
methods of disposition thereof specified by the Holders.  Without limiting the
foregoing, the Company will, as expeditiously as possible:

          (a) prepare and file with the Commission as soon as practicable,
          unless delayed pursuant to Section 8(e), the requisite registration
          statement to effect such Demand Registration and use its best efforts
          to cause such registration statement to become effective, provided
          that as far in advance as practical before filing such registration
          statement or any amendment thereto, the Company will furnish to the
          Holders who have elected to participate in such Demand Registration.
          copies of reasonably complete drafts of all such documents proposed to
          be fled (including exhibits), and any such Holder shall have the
          opportunity to object to any information pertaining solely to such
          Holder that is contained therein, and the Company will make the
          corrections reasonably requested by such Holder with respect to such
          information prior to filing any such registration statement or
          amendment;

          (b) prepare and file with the Commission such amendments and
          supplements to such registration statements, financial statements and
          any prospectus used in connection therewith as may be necessary to
          maintain the effectiveness of such registration statement and to
          comply with the provisions of the Act with respect to the disposition
          of all Shares covered by such registration statement, in accordance
          with the intended methods of disposition thereof, until the earlier of
          (i) such time as all of such Shares have been disposed of in
          accordance with the intended methods of disposition by the Holder or
          Holders thereof set forth in such registration statement and (ii) 180
          days after such registration  statement becomes effective;

          (c) promptly notify each Holder of Shares who has elected to
          participate in such Demand Registration and the underwriter or
          underwriters, if any:

               (i)  when such registration statement or any prospectus used in
               connection therewith, or any amendment or supplement thereto, has
               been filed and, with respect to such registration statement or
               any post-effective amendment thereto. when the same has become
               effective;

               (ii)  of the notification to the Company by the Commission of its
               initiation of any proceeding with respect to the issuance by the
               Commission of, or of the issuance by the Commission of, any stop
               order suspending the effectiveness of such registration
               statement; and

               (ii)  of the receipt by the Company of any notification with
               respect to the suspension of the qualification of any Shares for
               sale under the applicable Blue Sky Laws of any jurisdiction;

          (d) furnish to each Holder of Shares covered by such registration
          statement such number of conformed copies of such registration
          statement and of each amendment and supplement thereto (in each case
          including all exhibits and documents incorporated by reference), such
          number of copies of the prospectus contained in such registration
          statement (including each preliminary prospectus and any summary
          prospectus) and any other prospectus fled under Rule 424 promulgated
          under the Act relating to such Holder's Shares, and such other
          documents, as such Holder may reasonably request to facilitate the
          disposition of its Shares;

          (e) use its best efforts to register or qualify all Shares covered by
          such registration statement under

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          the Blue Sky Laws of such jurisdictions as each Holder thereof shall
          reasonably request, to keep such registration or qualification in
          effect for so long as such registration statement remains in effect,
          and take any other action which may be reasonably necessary or
          advisable to enable such Holder to consummate the disposition in such
          jurisdictions of the Shares owned by such Holder, except that the
          Company shall not for any such purpose be required (i) to qualify
          generally to do business as a foreign corporation in any jurisdiction
          wherein it would not but for the requirements of this Section 9(e) be
          obligated to be so qualified, or (ii) to subject itself to taxation in
          any such jurisdiction;

          (f) use its best efforts to cause all Shares covered by such
          registration statement to be registered with or approved by such other
          governmental agencies or authorities as may be necessary to enable
          each h older thereof to consummate the disposition of such Shares;

          (g) notify each Holder of Shares covered by such registration
          statement, at any time when a prospectus relating thereto is required
          to be delivered under the Act, of the happening of any event as a
          result of which any prospectus included in such registration
          statement, as then in effect, includes an untrue statement of a
          material fact or omits to state any material fact required to be
          stated therein or necessary to make the statements therein, in the
          light of the circumstances under which they were made, not misleading,
          and at the request of any such holder promptly prepare and furnish to
          such Holder a reasonable number of copies of a supplement to or an
          amendment of such prospectus as may be necessary so that, as
          thereafter delivered to the purchasers of such securities, such
          prospectus shall not include an untrue statement of a material fact or
          omit to state a material fact required to be stated therein or
          necessary to make the statements therein, in the light of the
          circumstances under which they were made, not misleading;

          (h) otherwise use its best efforts to comply with all applicable rules
          and regulations of the Commission, and make available to its security
          holders, as soon as reasonably practicable, an earnings statement
          covering the period of at least 12 months, but not more than 18
          months, beginning with the first full calendar month after the
          effective date of such registration statement, which earnings
          statement shall satisfy the provisions of Section 11 (a) of the Act
          and Rule 158 promulgated thereunder;

          (i) make available for inspection by any Holder who has elected to
          participate in such registration statement, any underwriter
          participating in any disposition pursuant to such registration
          statement and any attorney, accountant or other agent retained by any
          such Holder or underwriter (collectively, the "Inspectors"), all
          financial and other records, pertinent corporate documents and
          properties of the Company (collectively, the "Records") as shall be
          reasonably necessary to enable them to exercise their due diligence
          responsibility, and cause the Company's officers, directors and
          employees to supply all information reasonably requested by any such
          inspector in connection with such registration statement, and permit
          the inspectors to participate in the preparation of such registration
          statement and any prospectus contained therein and any amendment or
          supplement thereto.  Records which the Company determines, in good
          faith, to be confidential and which it notifies the inspectors are
          confidential shall not be disclosed by the inspectors unless (i) the
          disclosure of such Records is necessary to avoid or correct a
          misstatement or omission in the registration statement, (ii) the
          release of such Records is ordered pursuant to a subpoena or other
          order from a court of competent jurisdiction or (iii) the information
          in such Records has been made generally available to the public.  The
          Holder of Shares agrees by acquisition of such Shares that it will,
          upon learning that disclosure of such Records is sought in a court of
          competent jurisdiction, give notice to the Company and allow the
          Company, at the Company's expense, to undertake appropriate action to
          prevent disclosure of the Records deemed confidential;

          (j) provide a transfer agent and registrar for all Shares covered by
          such registration statement not later than the effective date of such
          registration statement; and

          (k) use its best efforts to cause all Shares covered by such
          registration statement to be listed, upon

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          official notice of issuance, on any securities exchange on which any
          of the securities of the same class as the Shares are then listed.

     The Company may require each Holder of Shares as to which any registration
is being effected to, and each such Holder, as a condition to including Shares
in such Demand Registration, shall, furnish the Company with such information
and affidavits regarding such Holder and the distribution of such securities as
the Company may from time to time reasonably request in writing in connection
with such Demand Registration.

     Each Holder of Shares agrees by acquisition of such Shares that upon
receipt of any notice from the Company of the happening of any event of the kind
described in Section 9(g), such Holder will forthwith discontinue such Holder's
disposition of Shares pursuant to the registration statement relating to such
Shares until such Holder's receipt of the copies of the supplemented or amended
prospectus contemplated by Section 9(g) and, if so directed by the Company, will
deliver to the Company (at the Company's expense) all copies, other than
permanent file copies, then in such Holder's possession of the prospectus
relating to such Shares current at the time of receipt of such notice.

     10.  UNDERWRITTEN OFFERINGS.  In the case of an underwritten Public
Offering, the Lead Underwriter, if any, shall be any underwriter or underwriters
as shall be selected by the Company, in its sole discretion.  The Company shall
enter into an underwriting agreement in customary form with such underwriter or
underwriters, which shall include, among other provisions, indemnities to the
effect and to the extent provided in Section 12 unless otherwise agreed to by
the Lead Underwriter and a Holder or Holders of Shares to be distributed by such
underwriters.  The Holders of Shares to be distributed by such underwriters
shall be parties to such underwriting agreement and may, at their option,
require that any or all of the representations and warranties by, and the other
agreements on the part of, the Company to and for the benefit of such
underwriters also be made to and for their benefit and that any or all of the
conditions precedent to the obligations of such underwriters under such
underwriting agreement also be conditions precedent to their obligations.
Unless otherwise agreed to by the Lead Underwriter and a Holder or Holders of
Shares to be distributed by such underwriters, no Holder of Shares shall be
required to make any representations or warranties to or agreements with the
Company or the underwriters other than representations, warranties or agreements
regarding such Holder and its ownership of the securities being registered on
its behalf and such Holder's intended method of distribution and any other
representation required by law.  No Holder may participate in such underwritten
offering unless such Holder agrees to sell its Shares on the basis provided in
such underwriting agreement and completes and executes all questionnaires,
powers of attorney, indemnities and other documents reasonably and customarily
required under the terms of such underwriting agreement.  If any Holder
disapproves of the terms of an underwriting prior to the effectiveness of the
registration statement, such Holder may elect to withdraw therefrom and from
such registration by notice to the Company and the Lead Underwriter.

     11.  INCIDENTAL REGISTRATION.  If the Company at any time (other than
pursuant to Section 10) proposes to register any of its Common Stock under the
Act for sale to the public, whether for its own account or for the account of
other security holders or both (except with respect to registration statements
on Forms S-4, S-8 or another form not available for registering the Shares for
sale to the public), each such time it will give written notice to the Holders
of its intention so to do.  Upon the written request of any such Holder,
received by the Company within 30 days after the giving of any such notice by
the Company, to register any of its Shares, the Company will use its best
efforts to cause the Shares as to which registration shall have been so
requested to be included in the securities to be covered by the registration
statement proposed to be filed by the Company, all to the extent requisite to
permit the sale or other disposition by the Holder of such Shares. In the event
that any Registration pursuant to this Section I I shall be, in whole or in
part, an underwritten public offering of Common Stock, the number of Shares to
be included in such an underwriting may be reduced (pro rata among the
requesting Holders based upon the number of Shares owned by such Holders and the
Company) if and to the extent that the managing underwriter shall be of the
opinion that such inclusion would adversely affect the marketing of the
securities to be sold by the Company.  Notwithstanding the foregoing provisions,
the Company may withdraw any registration statement referred to in this Section
11 without thereby incurring any liability to the Holders.

     12.  INDEMNIFICATION.

          (A) INDEMNIFICATION BY THE COMPANY. The Company shall, to the full
          extent permitted by law,

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          indemnify and hold harmless each Holder of Shares included in any
          registration statement fled in connection with a registration under
          Sections 8, 9 or 10 hereof, its directors and officers, and each other
          Person, if any, who controls any such Holder within the meaning of the
          Act, against any losses, claims, damages, expenses or liabilities,
          joint or several (together, "Losses"), to which such Holder or any
          such director or officer or controlling Person may become subject
          under the Act or otherwise, insofar as such Losses (or actions or
          proceedings, whether commenced or threatened, in respect thereof)
          arise out of or are based upon any untrue statement or alleged untrue
          statement of any material fact contained in any such registration
          statement, any preliminary prospectus, final prospectus or summary
          prospectus contained therein, or any amendment or supplement thereto,
          or any omission or alleged omission to state therein a material fact
          required to be stated therein or necessary to make the statements
          therein (in the case of a prospectus, in the light of the
          circumstances under which they were made) not misleading, and the
          Company will reimburse such Holder and each such director, officer and
          controlling Person for any legal or any other expenses reasonably
          incurred by them in connection with investigating or defending any
          such Loss (or action or proceeding in respect thereof); provided that
          the Company shall not be liable in any such case to the extent that
          any such Loss (or action or proceeding in respect thereof) arises out
          of or is based upon an untrue statement or alleged untrue statement or
          omission or alleged omission made in any such registration statement,
          preliminary prospectus, final prospectus, summary prospectus,
          amendment or supplement in reliance upon and in conformity with
          written information furnished to the Company through an instrument
          duly executed by such Holder specifically stating that it is for use
          in the preparation thereof.  Such indemnity shall remain in full force
          and effect regardless of any investigation made by or on behalf of
          such Holder or any such director, officer or controlling Person, and
          shall survive the transfer of Shares by such Holder.  The Company
          shall also indemnify each other Person who participates (including as
          an underwriter) in the offering or sale of Registrable Securities,
          their officers and directors and each other Person, if any, who
          controls any such participating Person within the meaning of the Act
          to the same extent as provided above with respect to Holders of
          Shares.

          (B) INDEMNIFICATION BY THE HOLDERS. Each Holder of Shares which are
          included or are to be included in any registration statement filed in
          connection with any registration under Sections 8, 9 or 10 hereof, as
          a condition to including Shares in such registration statement, shall,
          to the full extent permitted by law, indemnify and hold harmless the
          Company, its directors and officers, and each other Person, if any,
          who controls the Company within the meaning of the Act, against any
          Losses to which the Company or any such director or officer or
          controlling Person may become subject under the Act or otherwise,
          insofar as such Losses (or actions or proceedings, whether commenced
          or threatened, in respect thereof) arise out of or are based upon any
          untrue statement or alleged untrue statement of any material fact
          contained in any such registration statement, any preliminary
          prospectus, final prospectus or summary prospectus contained therein,
          or any amendment or supplement thereto, or any omission or alleged
          omission to state therein a material fact required to be stated
          therein or necessary to make the statements therein (in the case of a
          prospectus, in the light of the circumstances under which they were
          made) not misleading, if such untrue statement or alleged untrue
          statement or omission or alleged omission was made in reliance upon
          and in conformity with written information furnished to the Company
          through an instrument duly executed by such Holder specifically
          stating that it is for use in the preparation of such registration
          statement, preliminary prospectus, final prospectus, summary
          prospectus, amendment or supplement; provided, however, that the
          obligation to provide indemnification pursuant to this Section 12(b)
          shall be several, and not joint and several, among such indemnifying
          Parties on the basis of the number of Shares included in such
          registration statement and the aggregate amount which may be recovered
          from any Holder of Shares pursuant to the indemnification provided for
          in this Section 12(b) in connection with any registration and sale of
          Shares shall be limited to the total proceeds (including commissions
          and underwriting discounts) received by such Holder from the sale of
          such Shares.  Such indemnity shall remain in full force and effect
          regardless of any investigation made by or on behalf of the Company or
          any such director, officer or controlling Person and shall survive the
          transfer of such Shares by such Holder.  Such Holders shall also
          indemnify each other Person who participates (including as an
          underwriter) in the offering or sale of Registrable Securities, their
          officers and directors and each other

                                    Warrant
                                    Page 8
<PAGE>
 
          Person, if any, who controls any such participating Person within the
          meaning of the Act to the same ex-tent as provided above with respect
          to the Company.

          (C) NOTICES OF CLAIMS, ETC.  Promptly after receipt by an Indemnified
          Party of notice of the commencement of any action or proceeding
          involving a claim referred to in Section 12(a) or 12(b), such
          Indemnified Party will, if a claim in respect thereof is to be made
          against an indemnifying Party pursuant to such subsections, give
          written notice to the latter of the commencement of such action,
          provided that the failure of any Indemnified Party to give notice as
          provided herein shall not relieve the indemnifying Party of its
          obligations under the preceding paragraphs of this Section 12, except
          to the extent that the indemnifying Party is actually prejudiced by
          such failure to give notice.  In case any such action is brought
          against an Indemnified Party, the indemnifying Party shall be entitled
          to participate in and, unless, in the reasonable judgment of any
          Indemnified Party, a conflict of interest between such Indemnified
          Party and any indemnifying Party exists with respect to such claim, to
          assume the defense thereof, jointly with any other indemnifying Party
          similarly notified to the extent that it may wish, with counsel
          reasonably satisfactory to such Indemnified Party, and after notice
          from the Indemnifying Party to such Indemnified Party of its election
          so to assume the defense thereof, the indemnifying Party shall not be
          liable to such Indemnified Party for any legal or other expenses
          subsequently incurred by the latter in connection with the defense
          thereof other than reasonable costs of investigation; provided that
          the indemnified Party or Indemnified Parties shall have the right to
          employ one counsel to represent it or them if, in the reasonable
          judgment of the Indemnified Party or Indemnified Parties, it is
          advisable for it or them to be represented by separate counsel by
          reason of having legal defenses which are different from or in
          addition to those available to the indemnifying Party, and in that
          event the reasonable fees and expenses of such one counsel shall be
          paid by the indemnifying Party.  If the indemnifying Party is not
          entitled to, or elects not to, assume the defense of a claim, it will
          not be obligated to pay the fees and expenses of more than one counsel
          for the Indemnified Parties with respect to such claim, unless in the
          reasonable judgment of any Indemnified Party a conflict of interest
          may exist between such Indemnified Party and any other indemnified
          Parties with respect to such claim, in which event the indemnifying
          Party shall be obligated to pay the fees and expenses of such
          additional counsel for the Indemnified Parties or counsels.  No
          indemnifying Party shall consent to entry of any judgment or enter
          into any settlement without the consent of the Indemnified Party which
          does not include as an unconditional term thereof the giving by the
          claimant or plaintiff to such Indemnified Party of a release from all
          liability in respect to such claim or litigation.  No indemnifying
          Party shall be subject to any liability for any settlement made
          without its consent, which consent shall not be unreasonably withheld.

          (D) CONTRIBUTION.  If the indemnity and reimbursement obligation
          provided for in any subsection of this Section 12 is unavailable or
          insufficient to hold harmless an Indemnified Party in respect of any
          Losses (or actions or proceedings in respect thereof) referred to
          therein, then the indemnifying Party shall contribute to the amount
          paid or payable by the Indemnified Party as a result of such Losses
          (or actions or proceedings in respect thereof) in such proportion as
          is appropriate to reflect the relative fault of the indemnifying
          Party, on the one hand, and the Indemnified Party, on the other hand,
          in connection with statements or omissions which resulted in such
          Losses, as well as any other relevant equitable considerations.  The
          relative fault shall be determined by reference to, among other
          things, whether the untrue or alleged untrue statement of a material
          fact or the omission or alleged omission to state a material fact
          relates to information supplied by the indemnifying Party or the
          Indemnified Party and the parties' relative intent, knowledge, access
          to information and opportunity to correct or prevent such untrue
          statement or omission.  The parties hereto agree that it would not be
          just and equitable if contributions pursuant to this paragraph were to
          be determined by pro rata allocation or by any other method of
          allocation which does not take account of the equitable considerations
          referred to in the first sentence of this paragraph.  The amount paid
          by an Indemnified Party as a result of the Losses referred to in the
          first sentence of this Section 12(d) shall be deemed to include any
          legal and other expenses reasonably incurred by such Indemnified Party
          in connection with investigating or defending any Loss which is the
          subject of this Section 12(d).

                                    Warrant
                                    Page 9
<PAGE>
 
          No Indemnified Party guilty of fraudulent misrepresentation (within
          the meaning of Section 1 l(f) of the Act) shall be entitled to
          contribution from the Indemnifying Party if the indemnifying Party was
          not guilty of such fraudulent misrepresentation.

          (E) OTHER INDEMNIFICATION. Indemnification similar to that specified
          in the preceding paragraphs of this Section 12 (with appropriate
          modifications) shall be given by the Company and each Holder of Shares
          with respect to any required registration or other qualification of
          securities under any federal or state law or regulation of any
          governmental authority other than the Act reasonable and customary in
          scope and effect.  The provisions of this Section 12 shall be in
          addition to any other rights to indemnification or contribution which
          an Indemnified Party may have pursuant to law, equity, contract or
          otherwise.

          (F) INDEMNIFICATION PAYMENTS. The indemnification required by this
          Section 12 shall be made by periodic payments of the amount thereof
          during the course of the investigation or defense, as and when bills
          are received or Losses are incurred.

     13.  COVENANTS RELATING TO RULE 144.  The Company will file reports in
compliance with the Exchange Act, will comply with all rules and regulations of
the Commission applicable in connection with the use of Rule 144 and take such
other actions and furnish any Holder with such other information as such Holder
may request in order to avail itself of such rule or any other rule or
regulation of the Commission allowing such Holder to sell any Shares without
registration, and will, at its expense, forthwith upon the request of any
Holder, deliver to such Holder a certificate, signed by the Company's principal
financial officer, stating (a) the Company's name, address and telephone number
(including area code), (b) the Company's Internal Revenue Service identification
number, (c) the Company's Commission file number, (d) the number of shares of
each class of stock outstanding as shown by the most recent report or statement
published by the Company, and (e) whether the Company has filed the reports
required to be filed under the Exchange Act for a period of at least 90 days
prior to the date of such certificate and in addition has filed the most recent
annual report required to be filed thereunder. If at any time the Company is not
required to file reports in compliance with either Section 13 or Section 15(d)
of the Exchange Act, the Company at its expense will, forthwith upon the written
request of the Holder of any Shares, make available adequate current public
information with respect to the Company within the meaning of paragraph (c)(2)
of Rule 144.

     14.  DEFINITIONS.  Unless the context otherwise requires, (i) words of any
gender include each other gender; (ii) words using the singular or plural number
also include the plural or singular number, respectively; (iii) the terms
"hereof," "herein," "hereby" and derivative or similar words refer to this
entire Warrant; and (iv) the term "Section" refers to the specified Section of
this Warrant. Whenever this Warrant refers to a number of days, such number
shall refer to calendar days unless Business Days are specified. Except as
otherwise specifically indicated, the following terms will have the following
meanings for all purposes of this Warrant:

          (A) "BUSINESS DAY" means a day other than Saturday, Sunday or any
          other day on which banks located in the State of New York are
          authorized or obligated to close.

          (B) "COMMON STOCK" means shares of the Company's common stock, par
          value $.01 per share, as constituted on the date of this Warrant, and
          any stock into which such Common Stock shall have been changed or any
          stock resulting from any reclassification of such Common Stock.

          (C) "COMMISSION" means the United States Securities and Exchange
          Commission, or any successor governmental agency or authority.

          (D) "COMPANY" means IWC Services, Inc.

          (E) "EXCHANGE ACT " means the Securities Exchange Act of 1934, as
          amended, and the rules and regulations promulgated thereunder.

                                    Warrant
                                    Page 10
<PAGE>
 
          (F) "HOLDER" means the initial Holder of this Warrant and any
          transferee, successors or assigns.

          (G) "HOLDERS" means the initial Holders of the Warrants and any
          transferee. successors or assigns.

          (H) "INDEMNIFIED PARTY" means a party entitled to indemnity in
          accordance with Section 12.

          (I) "INDEMNIFYING PARTY" means a party obligated to provide indemnity
          in accordance with Section 12.

          (J) "INSPECTORS" has the meaning ascribed to it in Section 9(I).

          (K) "LEAD UNDERWRITER" means, with respect to any Public Offering, the
          underwriter managing such Public Offering.

          (L) "LOSSES" has the meaning ascribed to it in Section 12(a).

          (M) "NASD" means the National Association of Securities Dealers, inc.

          (N) "NOTES" means the $5,000,000 principal amount of 12% Senior
          Subordinated Notes being offered and sold by the Company pursuant to a
          Private Placement Memorandum dated December 12, 1997.

          (O) "PERSON" means any natural person, corporation, general
          partnership, limited partnership, proprietorship, other business
          organization, trust, union or association.

          (P) "PUBLIC OFFERING" means any offering of Common Stock to the
          public, either on behalf of the Company or any of its security
          Holders, pursuant to an effective registration statement under the
          Act.

          (Q) "REGISTRATION EXPENSES" means all expenses incident to the
          Company's performance of or compliance with its obligations under this
          Warrant to effect the registration of Shares in a registration under
          Sections 8, 9 or 10 hereof, including, without limitation, all
          registration, filing, securities exchange listing and NASD fees, all
          registration, filing, qualification and other fees and expenses of
          complying with state securities laws, all word processing, duplicating
          and printing expenses, messenger and delivery expenses, the fees and
          disbursements of counsel for the Company and of its independent public
          accountants, premiums and other costs of policies of insurance against
          liabilities arising out of the Public Offering of the Shares being
          registered and any fees and disbursements of underwriters customarily
          paid by issuers or Holders of securities, but excluding underwriting
          discounts and commissions or brokerage fees and transfer taxes, if
          any, in respect of Shares, which shall be payable by each Holder
          thereof.

          (R) "RULE 144" means Rule 144 promulgated by the Commission under the
          Act, and any successor provision thereto.

          (S) "ACT" means the Act of 1933, as amended. and the rules and
          regulations promulgated thereunder.

          (T) "SHARES" means the shares of Common Stock issuable to the Holders
          of the Warrants upon the exercise thereof, and any additional shares
          of Common Stock issued or distributed by way of a dividend, stock
          split or other distribution in respect of the Shares.

          (U) "WARRANT" means this Warrant.

          (V) "WARRANTS" means the series of Warrants being granted by the
          Company in connection with the

                                    Warrant
                                    Page 11
<PAGE>
 
          offering and sale of the Notes.

     15.  MISCELLANEOUS.

          (A) NOTICES. All notices, requests and other communications hereunder
          must be in writing and will be deemed to have been duly given only if
          delivered personally or by facsimile transmission or mailed (first
          class postage prepaid) to the parties at the following addresses or
          facsimile numbers: (i) if to the Holder, to the name, address and
          facsimile number set forth in the Subscription and Suitability
          Agreement executed in connection with the purchase of the Notes and
          this Warrant or any other address or facsimile number delivered to the
          Company in writing or to the name, address and facsimile number of any
          transferee of this Warrant as set forth on the form of Assignment
          attached hereto; and (ii) if to the Company, to IWC Services, Inc.,
          2800 Post Oak Boulevard, Suite 6300, Houston, Texas, 77056

          With respect to any other Holder of Shares, such notices, requests and
          other communications shall be sent to the addresses set forth in the
          stock transfer records regularly maintained by the Company.  All such
          notices, requests and other communications will (i) if delivered
          personally to the address as provided in this Section, be deemed given
          upon delivery, (ii) if delivered by facsimile transmission to the
          facsimile number as provided in this Section, be deemed given upon
          receipt, and (iii) if delivered by mail in the manner described above
          to the address as provided in this Section, be deemed given upon
          receipt (in each case regardless of whether such notice, request or
          other communication is received by any other Person to whom a copy of
          such notice is to be delivered pursuant to this Section 15(b)).  Any
          party from time to time may change its address, facsimile number or
          other information for the purpose of notices to that party by giving
          notice specifying such change to the other parties hereto.

          (B) WAIVER.  Any term or condition of this Warrant may be waived at
          any time by the Holder, but no such waiver shall be effective unless
          set forth in a written instrument duly executed by or on behalf of the
          Holder.  No waiver by the Holder of any term or condition of this
          Warrant, in any one or more instances, shall be deemed to be or
          construed as a waiver of the same term or condition of this Warrant on
          any future occasion.

          (C) SUCCESSORS AND ASSIGNS. This Warrant inures to the benefit of and
          is enforceable by the Holder hereof and the Holder's respective
          successors and assigns.

          (D) HEADINGS. The headings used in this Warrant have been inserted for
          convenience of reference only and do not define or limit the
          provisions hereof.

          (E) INVALID PROVISIONS. If any provision of this Warrant is held to be
          illegal, invalid or unenforceable under any present or future law, and
          if the rights or obligations of the Holder hereof will not be
          materially and adversely affected thereby, (i) such provision will be
          fully severable, (ii) this Warrant will be construed and enforced as
          if such illegal, invalid or unenforceable provision had never
          comprised a part hereof, (iii) the remaining provisions of this
          Warrant will remain in full force and effect and will not be affected
          by the illegal, invalid or unenforceable provision or by its severance
          herefrom and (iv) in lieu of such illegal, invalid or unenforceable
          provision, there will be added automatically as a part of this Warrant
          a legal, valid and enforceable provision as similar in terms to such
          illegal, invalid or unenforceable provision as may be possible.

          (F) GOVERNING LAW. This Warrant shall be governed by and construed in
          accordance with the laws of the State of Texas, without giving effect
          to the conflicts of laws principles thereof.

     IN WITNESS WHEREOF, this Warrant has been duly executed and delivered by
the duly authorized officer of

                                    Warrant
                                    Page 12
<PAGE>
 
the Company as of the date first above written.

Attest:                              IWC SERVICES, INC.



_____________________________        __________________________________ 
Secretary                            By: Its:

                                    [SEAL]





                                    Warrant
                                    Page 13
<PAGE>
 
                               IWC SERVICES, INC.
                             WARRANT EXERCISE FORM

               Number of Warrants Exercised _____________________

    The undersigned hereby irrevocably elects to exercise the right to purchase
represented by the within Warrant for, and to purchase thereunder,
_______________shares of the stock provided for therein, and requests that
certificates for such shares be issued in the name of:

_______________________________________
(Name and Social Security Number)

_______________________________________
(Street Address)

_______________________________________
(City, State, Zip Code)

and if said number of shares shall not be all the shares purchasable thereunder,
that a new Warrant for the balance remaining of the shares purchasable under the
within Warrant be registered in the name of the undersigned Warrantholder or his
Assignee as below indicated and delivered to the address stated below.

Dated:______________, 19____

_______________________________________
(Name of Warrantholder or Assignee)

_______________________________________
(Street Address)

_______________________________________
(City, State, Zip Code)

_______________________________________
(Signature of Warrantholder)

_______________________________________
(Signature of Warrantholder)


                                    Warrant
                                    Page 14
<PAGE>
 
                                   ASSIGNMENT
            (To Be Executed Only Upon the Assignment of the Warrant)
    For Value Received, the undersigned hereby sells assigns and transfers unto:

________________________________________
(Name and Social Security Number of Assignee)
________________________________________
(Street Address)
________________________________________
(City, State, Zip Code)

the within Warrant, hereby irrevocably constituting and appointing
________________________________ as his true and lawful attorney in fact to
transfer said Warrant on the books of the Company, with full power of
substitution in the premises.

Dated: __________________, 19____

________________________________________
(Signature of Warrantholder)

________________________________________
(Signature of Warrantholder)


Note:  The above signature must correspond with the name written upon the face
of this Warrant in every particular, without alteration or enlargement or any
change whatever unless this Warrant has been assigned.



                                    Warrant
                                    Page 15