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                                                                Exhibit 3.18

                              AMENDED AND RESTATED

                                     BYLAWS

                                       OF

                                    300, INC.

                               A TEXAS CORPORATION


                                DATE OF ADOPTION

                                 APRIL 23, 1997

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                                TABLE OF CONTENTS

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                                                                               Page
                                                                               
                                     ARTICLE 1
                                      OFFICES

Section 1.1.  Registered Office ..................................................1
Section 1.2.  Other Offices ......................................................1

                                     ARTICLE 2
                                    SHAREHOLDERS

Section 2.1.  Place of Meetings ..................................................1
Section 2.2.  Quorum; Adjournment of Meetings ....................................1
Section 2.3.  Annual Meetings ....................................................2
Section 2.4.  Special Meetings ...................................................2
Section 2.5.  Record Date ........................................................2
Section 2.6.  Notice of Meetings .................................................3
Section 2.7.  Shareholder List ...................................................4
Section 2.8.  Proxies ............................................................4
Section 2.9.  Voting; Election; Inspectors .......................................4
Section 2.10. Conduct of Meetings ................................................5
Section 2.11. Treasury Stock .....................................................6
Section 2.12. Action Without Meeting .............................................6

                                     ARTICLE 3
                                 BOARD OF DIRECTORS

Section 3.1.  Power; Number; Term of Office ......................................6
Section 3.2.  Quorum; Voting .....................................................7
Section 3.3.  Place of Meetings; Order of Business ...............................7
Section 3.4.  First Meeting ......................................................7
Section 3.5.  Regular Meetings ...................................................7
Section 3.6.  Special Meetings ...................................................8
Section 3.7.  Removal ............................................................8
Section 3.8.  Vacancies; Increases in the Number of Directors ....................8
Section 3.9.  Compensation .......................................................8
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<Table>
                                                                              
Section 3.10. Action Without a Meeting; Telephone Conference Meeting .............8
Section 3.11. Approval or Ratification of Acts or Contracts by Shareholders ......9

                                     ARTICLE 4
                                     COMMITTEES

Section 4.1.  Designation; Powers ................................................9
Section 4.2.  Procedure; Meetings; Quorum ........................................9
Section 4.3.  Substitution and Removal of Members; Vacancies ....................10

                                     ARTICLES 5
                                      OFFICERS

Section 5.1.  Number, Titles and Term of Office .................................10
Section 5.2.  Powers and Duties of the Chairman of the Board ....................10
Section 5.3.  Powers and Duties of the President ................................11
Section 5.4.  Powers and Duties of the Vice Chairman of the Board ...............11
Section 5.5.  Vice Presidents ...................................................11
Section 5.6.  Secretary .........................................................11
Section 5.7.  Assistant Secretaries .............................................12
Section 5.8.  Treasurer .........................................................12
Section 5.9.  Assistant Treasurers ..............................................12
Section 5.10. Action with Respect to Securities of Other Corporations ...........12
Section 5.11. Delegation ........................................................13

                                     ARTICLE 6
                                   CAPITAL STOCK

Section 6.1.  Certificates of Stock .............................................13
Section 6.2.  Transfer of Shares ................................................13
Section 6.3.  Ownership of Shares ...............................................13
Section 6.4.  Regulations Regarding Certificates ................................14
Section 6.5.  Lost or Destroyed Certificates.....................................14

                                     ARTICLE 7
                              MISCELLANEOUS PROVISIONS

Section 7.1.  Fiscal Year .......................................................14
Section 7.2.  Corporate Seal.....................................................14
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<Table>
                                                                              
Section 7.3.  Notice and Waiver of Notice .......................................14
Section 7.4.  Facsimile Signatures ..............................................15
Section 7.5.  Reliance upon Books, Reports and Records ..........................15
Section 7.6.  Application of Bylaws .............................................15

                                     ARTICLE 8
                     INDEMNIFICATION OF OFFICERS AND DIRECTORS

Section 8.1.  Indemnification ...................................................15
Section 8.2.  Nonexclusivity ....................................................16
Section 8.3.  Insurance .........................................................16
Section 8.4.  Witnesses .........................................................16

                                     ARTICLE 9
                                     AMENDMENTS

Section 9.1.  Amendments ........................................................17
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                                    * * * * *

                              AMENDED AND RESTATED

                                     BYLAWS

                                       OF

                                    300, INC.

                                    * * * * *

                                    ARTICLE 1
                                     OFFICES

     SECTION 1.1.  REGISTERED OFFICE. The registered office of the Corporation
required by the state of incorporation of the Corporation to be maintained in
the state of incorporation of the Corporation shall be the registered office
named in the charter documents of the Corporation, or such other office as may
be designated from time to time by the Board of Directors in the manner provided
by law.

     SECTION 1.2.  OTHER OFFICES. The Corporation may also have offices at such
other places both within and without the state of incorporation of the
Corporation as the Board of Directors may from time to time determine or the
business of the Corporation may require.

                                    ARTICLE 2
                                  SHAREHOLDERS

     SECTION 2.1.  PLACE OF MEETINGS. All meetings of the shareholders shall be
held at the principal office of the Corporation, or at such other place within
or without the state of incorporation of the Corporation as shall be specified
or fixed in the notices or waivers of notice thereof.

     SECTION 2.2.  QUORUMS; ADJOURNMENT OF MEETINGS. Unless otherwise required
by law or provided in the charter documents of the Corporation or these Bylaws,
(i) the holders of a majority of the stock issued and outstanding and entitled
to vote thereat, present in person or represented by proxy, shall constitute a
quorum at any meeting of shareholders for the transaction of business, (ii) in
all matters other than election of directors, the affirmative vote of the
holders of a majority of such stock so present or represented at any meeting of
shareholders at which a quorum is present shall constitute the act of the
shareholders, and (iii) where a separate vote by a class or classes is required,
a majority of the outstanding shares of such class or classes, present in person
or represented by

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proxy shall constitute a quorum entitled to take action with respect to that
vote on that matter and the affirmative vote of the majority of the shares of
such class or classes present in person or represented by proxy at the meeting
shall be the act of such class. The shareholders present at a duly organized
meeting may continue to transact business until adjournment, notwithstanding the
withdrawal of enough shareholders to leave less than a quorum, subject to the
provisions of clauses (ii) and (iii) above.

     Directors shall be elected by a plurality of the votes of the shares
present in person or represented by proxy at the meeting and entitled to vote on
the election of directors.

     Notwithstanding the other provisions of the charter documents of the
Corporation or these Bylaws, the chairman of the meeting or the holders of a
majority of the issued and outstanding stock, present in person or represented
by proxy and entitled to vote thereat, at any meeting of shareholders, whether
or not a quorum is present, shall have the power to adjourn such meeting from
time to time, without any notice other than announcement at the meeting of the
time and place of the holding of the adjourned meeting. If the adjournment is
for more than thirty (30) days, or if after the adjournment a new record date is
fixed for the adjourned meeting, a notice of the adjourned meeting shall be
given to each shareholder of record entitled to vote at such meeting. At such
adjourned meeting at which a quorum shall be present or represented any business
may be transacted which might have been transacted at the meeting as originally
called.

     SECTION 2.3.  ANNUAL MEETINGS. An annual meeting of the shareholders, for
the election of directors to succeed those whose terms expire and for the
transaction of such other business as may properly come before the meeting,
shall be held at such place (within or without the state of incorporation of the
Corporation), on such date, and at such time as the Board of Directors shall fix
and set forth in the notice of the meeting, which date shall be within thirteen
(13) months subsequent to the last annual meeting of shareholders.

     SECTION 2.4.  SPECIAL MEETINGS. Unless otherwise provided in the charter
documents of the Corporation, special meetings of the shareholders for any
purpose or purposes may be called at any time by the Chairman of the Board, by
the Vice Chairman of the Board or by the President, or by a majority of the
Board of Directors, or by a majority of the executive committee (if any), at
such time and at such place as may be stated in the notice of the meeting.
Business transacted at a special meeting shall be confined to the purpose(s)
stated in the notice of such meeting.

     SECTION 2.5.  RECORD DATE. For the purpose of determining shareholders
entitled to notice of or to vote at any meeting of shareholders, or any
adjournment thereof, or entitled to receive payment of any dividend or other
distribution or allotment of any rights, or entitled to exercise any rights in
respect of any change, conversion or exchange of stock or for the purpose of any
other

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lawful action, the Board of Directors of the Corporation may fix a date as the
record date for any such determination of shareholders, which record date shall
not precede the date on which the resolutions fixing the record date are adopted
and which record date shall not be more than sixty (60) days nor less than ten
(10) days before the date of such meeting of shareholders, nor more than sixty
(60) days prior to any other action to which such record date relates.

     If the Board of Directors does not fix a record date for any meeting of the
shareholders, the record date for determining shareholders entitled to notice of
or to vote at such meeting shall be at the close of business on the day next
preceding the day on which notice is given, or, if in accordance with Article 7,
Section 7.3 of these Bylaws notice is waived, at the close of business on the
day next preceding the day on which the meeting is held. The record date for
determining shareholders for any other purpose (other than the consenting to
corporate action in writing without a meeting) shall be at the close of business
on the day on which the Board of Directors adopts the resolution relating
thereto. A determination of shareholders of record entitled to notice of or to
vote at a meeting of shareholders shall apply to any adjournment of the meeting;
provided, however, that the Board of Directors may fix a new record date for the
adjourned meeting.

     For the purpose of determining the shareholders entitled to consent to
corporate action in writing without a meeting, the Board of Directors may fix a
record date, which record date shall not precede the date upon which the
resolution fixing the record date is adopted by the Board of Directors, and
which date shall not be more than ten (10) days after the date upon which the
resolution fixing the record date is adopted by the Board of Directors. If the
Board of Directors does not fix the record date, the record date for determining
shareholders entitled to consent to corporate action in writing without a
meeting, when no prior action by the Board of Directors is necessary, shall be
the first date on which a signed written consent setting forth the action taken
or proposed to be taken is delivered to the Corporation at its registered office
in the state of incorporation of the Corporation or at its principal place of
business. If the Board of Directors does not fix the record date, and prior
action by the Board of Directors is necessary, the record date for determining
shareholders entitled to consent to corporate action in writing without a
meeting shall be at the close of business on the day on which the Board of
Directors adopts the resolution taking such prior action.

     SECTION 2.6.  NOTICE OF MEETINGS. Written notice of the place, date and
hour of all meetings, and, in case of a special meeting, the purpose or purposes
for which the meeting is called, shall be given by or at the direction of the
Chairman of the Board, the President, the Vice Chairman of the Board, or the
President, the Secretary or the other person(s) calling the meeting to each
shareholder entitled to vote thereat not less than ten (10) nor more than sixty
(60) days before the date of the meeting. Such notice may be delivered either
personally or by mail. If mailed, notice is given when

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deposited in the United States mail, postage prepaid, directed to the
shareholder at such shareholder's address as it appears on the records of the
Corporation.

     SECTION 2.7.  SHAREHOLDER LIST. A complete list of shareholders entitled
to vote at any meeting of shareholders, arranged in alphabetical order for each
class of stock and showing the address of each such shareholder and the number
of shares registered in the name of such shareholder, shall be open to the
examination of any shareholder, for any purpose germane to the meeting, during
ordinary business hours, for a period of at least ten (10) days prior to the
meeting, either at a place within the city where the meeting is to be held,
which place shall be specified in the notice of the meeting, or, if not so
specified, at the place where the meeting is to be held. The shareholder list
shall also be produced and kept at the time and place of the meeting during the
whole time thereof, and may be inspected by any shareholder who is present.

     SECTION 2.8.  PROXIES. Each shareholder entitled to vote at a meeting of
shareholders or to express consent or dissent to a corporate action in writing
without a meeting may authorize another person or persons to act for him by
proxy. Proxies for use at any meeting of shareholders shall be filed with the
Secretary, or such other officer as the Board of Directors may from time to time
determine by resolution, before or at the time of the meeting. All proxies shall
be received and taken charge of and all ballots shall be received and canvassed
by the secretary of the meeting, who shall decide all questions touching upon
the qualification of voters, the validity of the proxies, and the acceptance or
rejection of votes, unless an inspector or inspectors shall have been appointed
by the chairman of the meeting, in which event such inspector or inspectors
shall decide all such questions.

     No proxy shall be valid after eleven (11) months from its date, unless the
proxy provides for a longer period. Each proxy shall be revocable unless
expressly provided therein to be irrevocable and coupled with an interest
sufficient in law to support an irrevocable power.

     Should a proxy designate two or more persons to act as proxies, unless such
instrument shall provide the contrary, a majority of such persons present at any
meeting at which their powers thereunder are to be exercised shall have and may
exercise all the powers of voting or giving consents thereby conferred, or if
only one be present, then such powers may be exercised by that one; or, if an
even number attend and a majority do not agree on any particular issue, each
proxy so attending shall be entitled to exercise such powers in respect of such
portion of the shares as is equal to the reciprocal of the fraction equal to the
number of proxies representing such shares divided by the total number of shares
represented by such proxies.

     SECTION 2.9.  VOTING; ELECTION; INSPECTORS. Unless otherwise required by
law or provided in the charter documents of the Corporation, each shareholder
shall on each matter submitted to a vote at a meeting of shareholders have one
vote for each share of the stock entitled to vote which is

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registered in his name on the record date for the meeting. For the purposes
hereof, each election to fill a directorship shall constitute a separate matter.
Shares registered in the name of another corporation, domestic or foreign, may
be voted by such officer, agent or proxy as the bylaws (or comparable body) of
such corporation may determine. Shares registered in the name of a deceased
person may be voted by the executor or administrator of such person's estate,
either in person or by proxy.

     All voting, except as required by the charter documents of the Corporation
or where otherwise required by law, may be by a voice vote; provided, however,
upon request of the chairman of the meeting or upon demand therefor by
shareholders holding a majority of the issued and outstanding stock present in
person or by proxy at any meeting a stock vote shall be taken. Every stock vote
shall be taken by written ballots, each of which shall state the name of the
shareholder or proxy voting and such other information as may be required under
the procedure established for the meeting. All elections of directors shall be
by written ballots, unless otherwise provided in the charter documents of the
Corporation.

     At any meeting at which a vote is taken by written ballots, the chairman of
the meeting may appoint one or more inspectors, each of whom shall subscribe an
oath or affirmation to execute faithfully the duties of inspector at such
meeting with strict impartiality and according to the best of such inspector's
ability. Such inspector shall receive the written ballots, count the votes, and
make and sign a certificate of the result thereof. The chairman of the meeting
may appoint any person to serve as inspector, except no candidate for the office
of director shall be appointed as an inspector.

     Unless otherwise provided in the charter documents of the Corporation,
cumulative voting for the election of directors shall be prohibited.

     SECTION 2.10. CONDUCT OF MEETINGS. The meetings of the shareholders shall
be presided over by the Chairman of the Board, or, if the Chairman of the Board
is not present, by the President, or, if the President is not present, by the
Vice Chairman of the Board, or, if neither the Chairman of the Board, the
President nor the Vice Chairman of the Board is present, by a chairman elected
at the meeting. The Secretary of the Corporation, if present, shall act as
secretary of such meetings, or, if the Secretary is not present, an Assistant
Secretary shall so act; if neither the Secretary or an Assistant Secretary is
present, then a secretary shall be appointed by the chairman of the meeting.

     The chairman of any meeting of shareholders shall determine the order of
business and the procedure at the meeting, including such regulation of the
manner of voting and the conduct of discussion as seem to the chairman in order.

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     SECTION 2.11. TREASURY STOCK. The Corporation shall not vote, directly or
indirectly, shares of its own stock owned by it and such shares shall not be
counted for quorum purposes. Nothing in this Section 2.11 shall be construed as
limiting the right of the Corporation to vote stock, including but not limited
to its own stock, held by it in a fiduciary capacity.

     SECTION 2.12. ACTION WITHOUT MEETING. Unless otherwise provided in the
charter documents of the Corporation, any action permitted or required by law,
the charter documents of the Corporation or these Bylaws to be taken at a
meeting of shareholders, may be taken without a meeting, without prior notice
and without a vote, if a consent or consents in writing, setting forth the
action so taken, shall be signed by the holders of all the outstanding shares
entitled to vote on such action and shall be delivered to the Corporation by
delivery to its registered office in the state of incorporation, its principal
place of business, or an officer or agent of the Corporation having custody of
the book in which proceedings of meetings of shareholders are recorded. Delivery
made to the Corporation's registered office shall be by hand or by certified or
registered mail, return receipt requested.

     Every written consent shall bear the date of signature of each shareholder
who signs the consent, and no written consent shall be effective to take the
corporate action referred to therein unless, within sixty (60) days of the
earliest dated consent delivered in the manner required by this Section to the
Corporation, written consents signed by a sufficient number of holders to take
action are delivered to the Corporation by delivery to its registered office in
the state of incorporation, its principal place of business, or an officer or
agent of the Corporation having custody of the book in which proceedings of
meetings of shareholders are recorded. Delivery made to the Corporation's
registered office shall be by hand or by certified or registered mail, return
receipt requested.

                                    ARTICLE 3
                               BOARD OF DIRECTORS

     SECTION 3.1.  POWER; NUMBER; TERM OF OFFICE. The business and affairs of
the Corporation shall be managed by or under the direction of the Board of
Directors, and, subject to the restrictions imposed by law or the charter
documents of the Corporation, the Board of Directors may exercise all the powers
of the Corporation.

     The number of directors which shall constitute the whole Board of Directors
shall be determined from time to time by the Board of Directors (provided that
no decrease in the number of directors which would have the effect of shortening
the term of an incumbent director may be made by the Board of Directors). If the
Board of Directors makes no such determination, the number of directors shall be
one. Each director shall hold office for the term for which such director is

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elected, and until such director's successor shall have been elected and
qualified or until such director's earlier death, resignation or removal.

     Unless otherwise provided in the charter documents of the Corporation,
directors need not be shareholders nor residents of the state of incorporation
of the Corporation.

     SECTION 3.2.  QUORUM; VOTING. Unless otherwise provided in the charter
documents of the Corporation, a majority of the number of directors fixed in
accordance with Section 3.1 shall constitute a quorum for the transaction of
business of the Board of Directors and the vote of a majority of the directors
present at a meeting at which a quorum is present shall be the act of the Board
of Directors.

     SECTION 3.3.  PLACE OF MEETINGS; ORDER OF BUSINESS. The directors may hold
their meetings and may have an office and keep the books of the Corporation,
except as otherwise provided by law, in such place or places, within or without
the state of incorporation of the Corporation, as the Board of Directors may
from time to time determine. At all meetings of the Board of Directors business
shall be transacted in such order as shall from time to time be determined by
the Chairman of the Board, or in the Chairman of the Board's absence by the
President, or in the President's absence by the Vice Chairman of the Board.

     SECTION 3.4.  FIRST MEETING. Each newly elected Board of Directors may hold
its first meeting for the purpose of organization and the transaction of
business, if a quorum is present, immediately after and at the same place as the
annual meeting of the shareholders. Notice of such meeting shall not be
required. At the first meeting of the Board of Directors in each year at which a
quorum shall be present, held after the annual meeting of shareholders, the
Board of Directors shall elect the officers of the Corporation.

     SECTION 3.5.  REGULAR MEETINGS. Regular meetings of the Board of Directors
shall be held at such times and places as shall be designated from time to time
by the Chairman of the Board, or in the absence of the Chairman of the Board, by
the President, or in the President's absence, by the Vice Chairman of the Board,
or in the absence of the Vice Chairman of the Board, by another officer of the
Corporation. Notice of such regular meetings shall not be required.

     SECTION 3.6.  SPECIAL MEETINGS. Special meetings of the Board of Directors
may be called by the Chairman of the Board, the President or the Vice Chairman
of the Board or, on the written request of any director, by the Secretary, in
each case on at least twenty-four (24) hours' personal, written, telegraphic,
cable or wireless notice to each director. Such notice, or any waiver thereof
pursuant to Article 7, Section 7.3 hereof, need not state the purpose or
purposes of such meeting, except as may otherwise be required by law or
provided for in the charter documents of the

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Corporation or these Bylaws. Meetings may be held at any time without notice if
all the directors are present or if those not present waive notice of the
meeting in writing.

     SECTION 3.7.  REMOVAL. Any director or the entire Board of Directors may be
removed with or without cause, by the holders of a majority of the shares then
entitled to vote at an election of directors.

     SECTION 3.8.  VACANCIES; INCREASES IN THE NUMBER OF DIRECTORS. Unless
otherwise provided in the charter documents of the Corporation, vacancies
existing on the Board of Directors for any reason may be filled by the
affirmative vote of a majority of the directors then in office, although less
than a quorum, or by a sole remaining director; and any director so chosen shall
hold office until the next annual election and until such director's successor
shall have been elected and qualified, or until such director's earlier death,
resignation or removal.

     SECTION 3.9.  COMPENSATION. No compensation shall be paid to directors and
members of standing committees, if any, for their services in such capacities,
provided, however, that they shall be reimbursed for all reasonable expenses
incurred in attending and returning from meetings of the Board of Directors.

     SECTION 3.10. ACTION WITHOUT A MEETING; TELEPHONE CONFERENCE MEETING.
Unless otherwise restricted by the charter documents of the Corporation, any
action required or permitted to be taken at any meeting of the Board of
Directors or any committee designated by the Board of Directors may be taken
without a meeting if all members of the Board of Directors or committee, as the
case may be, consent thereto in writing, and the writing or writings are filed
with the minutes of proceedings of the Board of Directors or committee. Such
consent shall have the same force and effect as a unanimous vote at a meeting,
and may be stated as such in any document or instrument filed with the Secretary
of State of the state of incorporation of the Corporation.

     Unless otherwise restricted by the charter documents of the Corporation,
subject to the requirement for notice of meetings, members of the Board of
Directors, or members of any committee designated by the Board of Directors, may
participate in a meeting of such Board of Directors or committee, as the case
may be, by means of a conference telephone connection or similar communications
equipment by means of which all persons participating in the meeting can hear
each other, and participation in such a meeting shall constitute presence in
person at such meeting, except where a person participates in the meeting for
the express purpose of objecting to the transaction of any business on the
ground that the meeting is not lawfully called or convened.

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     SECTION 3.11. APPROVAL OR RATIFICATION OF ACTS OR CONTRACTS BY
SHAREHOLDERS. The Board of Directors in its discretion may submit any act or
contract for approval or ratification at any annual meeting of the shareholders,
or at any special meeting of the shareholders called for the purpose of
considering any such act or contract; and any act or contract that shall be
approved or be ratified by the vote of the shareholders holding a majority of
the issued and outstanding shares of stock of the Corporation entitled to vote
and present in person or by proxy at such meeting (provided that a quorum is
present) shall be as valid and as binding upon the Corporation and upon all the
shareholders as if it has been approved or ratified by every shareholder of the
Corporation. In addition, any such act or contract may be approved or ratified
by the written consent of shareholders holding a majority of the issued and
outstanding shares of capital stock of the Corporation entitled to vote, and
such consent shall be as valid and binding upon the Corporation and upon all the
shareholders as if it had been approved or ratified by every shareholder of the
Corporation.

                                    ARTICLE 4
                                   COMMITTEES

     SECTION 4.1.  DESIGNATION; POWERS. The Board of Directors may, by
resolution passed by a majority of the whole board, designate one or more
committees, including, if they shall so determine, an executive committee, with
each such committee to consist of one or more of the directors of the
Corporation. Any such designated committee shall have and may exercise such of
the powers and authority of the Board of Directors in the management of the
business and affairs of the Corporation as may be provided in such resolution,
except that no such committee shall have the power or authority of the Board of
Directors in reference to amending the charter documents of the Corporation,
adopting an agreement of merger or consolidation, recommending to the
shareholders the sale, lease or exchange of all or substantially all of the
Corporation's property and assets, recommending to the shareholders a
dissolution of the Corporation or a revocation of a dissolution of the
Corporation, or amending, altering or repealing these Bylaws or adopting new
bylaws for the Corporation. Any such designated committee may authorize the seal
of the Corporation to be affixed to all papers which may require it. In addition
to the above, such committee or committees shall have such other powers and
limitations of authority as may be determined from time to time by the Board of
Directors.

     SECTION 4.2.  PROCEDURE; MEETINGS; QUORUM. Any committee designated
pursuant to this Article 4 shall keep regular minutes of its actions and
proceedings in a book provided for that purpose and report the same to the Board
of Directors at its meeting next succeeding such action, shall fix its own rules
or procedures, and shall meet at such times and at such place or places as may
be provided by such rules, or by such committee or the Board of Directors.
Should a committee fail to fix its own rules, the provisions of these Bylaws,
pertaining to the calling of meetings and conduct of business by the Board of
Directors, shall apply as nearly as may be possible. At every meeting

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of any such committee, the presence of a majority of all the members thereof
shall constitute a quorum, except as provided in Section 4.3 of this Article 4,
and the affirmative vote of a majority of the members present shall be necessary
for the adoption by it of any resolution.

     SECTION 4.3.  SUBSTITUTION AND REMOVAL OF MEMBERS; VACANCIES. The Board of
Directors may designate one or more directors as alternate members of any
committee, who may replace any absent or disqualified member at any meeting of
such committee. In the absence or disqualification of a member of a committee,
the member or members present at any meeting and not disqualified from voting,
whether or not constituting a quorum, may unanimously appoint another member of
the Board of Directors to act at the meeting in the place of the absent or
disqualified member. The Board of Directors shall have the power at any time to
remove any member(s) of a committee and to appoint other directors in lien of
the person(s) so removed and shall also have the power to fill vacancies in a
committee.

                                    ARTICLE 5
                                    OFFICERS

     SECTION 5.1.  NUMBER; TITLES AND TERM OF OFFICE. The officers of the
Corporation shall be a Chairman of the Board, President, one or more Vice
Presidents (any one or more of whom may be designated Executive Vice President
or Senior Vice President), a Treasurer, a Secretary, and such other officers as
the Board of Directors may from time to time elect or appoint (including, but
not limited to, a Vice Chairman of the Board, one or more Assistant Secretaries
and one or more Assistant Treasurers). Each officer shall hold office until such
officer's successor shall be duly elected and shall qualify or until such
officer's death or until such officer shall resign or shall have been removed.
Any number of offices may be held by the same person, unless the charter
documents of the Corporation provide otherwise. Except for the Chairman of the
Board and the Vice Chairman of the Board, no officer need be a director.

     SECTION 5.2.  POWERS AND DUTIES OF THE CHAIRMAN OF THE BOARD. The Chairman
of the Board shall be the chief executive officer of the Corporation. Subject to
the control of the Board of Directors and the Executive Committee (if any), the
Chairman of the Board shall have general executive charge, management and
control of the properties, business and operations of the Corporation with all
such powers as may be reasonably incident to such responsibilities; may agree
upon and execute all leases, contracts, evidences of indebtedness and other
obligations in the name of the Corporation and may sign all certificates for
shares of capital stock of the Corporation; and shall have such other powers and
duties as designated in accordance with these Bylaws and as from time to time
may be assigned to the Chairman of the Board by the Board of Directors. The
Chairman of the Board shall preside at all meetings of the shareholders and of
the Board of Directors.

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     SECTION 5.3.  POWERS AND DUTIES OF THE PRESIDENT. Unless the Board of
Directors otherwise determines, the President shall have the authority to agree
upon and execute all leases, contracts, evidences of indebtedness and other
obligations in the name of the Corporation; and unless the Board of Directors
otherwise determines, the President shall, in the absence of the Chairman of the
Board or if there be no Chairman of the Board (should the President be a
director) preside at all meetings of the shareholders and of the Board of
Directors; and the President shall have such other powers and duties as
designated in accordance with these Bylaws and as from time to time may be
assigned to the President by the Board of Directors or the Chairman of the
Board.

     SECTION 5.4.  POWERS AND DUTIES OF THE VICE CHAIRMAN OF THE BOARD. The
Board of Directors may assign areas of responsibility to the Vice Chairman of
the Board, and, in such event, and subject to the overall direction of the
Chairman of the Board and the Board of Directors, the Vice Chairman of the Board
shall be responsible for supervising the management of the affairs of the
Corporation and its subsidiaries within the area or areas assigned and shall
monitor and review on behalf of the Board of Directors all functions within such
corresponding area or areas of the Corporation and each such subsidiary of the
Corporation. In the absence of the President, or in the event of the President's
inability or refusal to act, the Vice Chairman of the Board shall perform the
duties of the President, and when so acting shall have all the powers of and be
subject to all the restrictions upon the President. Further, the Vice Chairman
of the Board shall have such other powers and duties as designated in
accordance with these Bylaws and as from time to time may be assigned to the
Vice Chairman of the Board by the Board of Directors or the Chairman of the
Board.

     SECTION 5.5.  VICE PRESIDENTS. Each Vice President shall at all times
possess power to sign all certificates, contracts and other instruments of the
Corporation, except as otherwise limited in writing by the Chairman of the
Board, the President or the Vice Chairman of the Board of the Corporation. Each
Vice President shall have such other powers and duties as from time to time may
be assigned to such Vice President by the Board of Directors, the Chairman of
the Board, the President or the Vice Chairman of the Board.

     SECTION 5.6.  SECRETARY. The Secretary shall keep the minutes of all
meetings of the Board of Directors, committees of the Board of Directors and the
shareholders, in books provided for that purpose; shall attend to the giving and
serving of all notices; may in the name of the Corporation affix the seal of the
Corporation to all contracts and attest the affixation of the seal of the
Corporation thereto; may sign with the other appointed officers all certificates
for shares of capital stock of the Corporation; shall have charge of the
certificate books, transfer books and stock ledgers, and such other books and
papers as the Board of Directors may direct, all of which shall at all
reasonable times be open to inspection of any director upon application at the
office of the Corporation during business hours; shall have such other powers
and duties as designated in these Bylaws and as from time to time may be
assigned to the Secretary by the Board of Directors, the

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Chairman of the Board, the President or the Vice Chairman of the Board; and
shall in general perform all acts incident to the office of Secretary, subject
to the control of the Board of Directors, the Chairman of the Board, the
President or the Vice Chairman of the Board.

     SECTION 5.7.  ASSISTANT SECRETARIES. Each Assistant Secretary shall have
the usual powers and duties pertaining to such offices, together with such other
powers and duties as designated in these Bylaws and as from time to time may be
assigned to an Assistant Secretary by the Board of Directors, the Chairman of
the Board, the President, the Vice Chairman of the Board, or the Secretary. The
Assistant Secretaries shall exercise the powers of the Secretary during that
officer's absence or inability or refusal to act.

     SECTION 5.8.  TREASURER. The Treasurer shall have responsibility for the
custody and control of all the funds and securities of the Corporation, and
shall have such other powers and duties as designated in these Bylaws and as
from time to time may be assigned to the Treasurer by the Board of Directors,
the Chairman of the Board, the President or the Vice Chairman of the Board. The
Treasurer shall perform all acts incident to the position of Treasurer, subject
to the control of the Board of Directors, the Chairman of the Board, the
President and the Vice Chairman of the Board; and the Treasurer shall, if
required by the Board of Directors, give such bond for the faithful discharge of
the Treasurer's duties in such form as the Board of Directors may require.

     SECTION 5.9.  ASSISTANT TREASURERS. Each Assistant Treasurer shall have the
usual powers and duties pertaining to such office, together with such other
powers and duties as designated in these Bylaws and as from time to time may be
assigned to each Assistant Treasurer by the Board of Directors, the Chairman of
the Board, the President, the Vice Chairman of the Board, or the Treasurer. The
Assistant Treasurers shall exercise the powers of the Treasurer during that
officer's absence or inability or refusal to act.

     SECTION 5.10. ACTION WITH RESPECT TO SECURITIES OF OTHER CORPORATIONS.
Unless otherwise directed by the Board of Directors, the Chairman of the
Board, the President or the Vice Chairman of the Board, together with the
Secretary or any Assistant Secretary shall have power to vote and otherwise act
on behalf of the Corporation, in person or by proxy, at any meeting of security
holders of or with respect to any action of security holders of any other
corporation in which this Corporation may hold securities and otherwise to
exercise any and all rights and powers which this Corporation may possess by
reason of its ownership of securities in such other corporation.

     SECTION 5.11. DELEGATION. For any reason that the Board of Directors may
deem sufficient, the Board of Directors may, except where otherwise provided by
statute, delegate the powers or duties of any officer to any other person, and
may authorize any officer to delegate specified duties

                                      -12-
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of such office to any other person. Any such delegation or authorization by the
Board shall be effected from time to time by resolution of the Board of
Directors.

                                    ARTICLE 6
                                  CAPITAL STOCK

     SECTION 6.1.  CERTIFICATES OF STOCK. The certificates for shares of the
capital stock of the Corporation shall be in such form, not inconsistent with
that required by law and the charter documents of the Corporation, as shall be
approved by the Board of Directors. Every holder of stock represented by
certificates shall be entitled to have a certificate signed by or in the name of
the Corporation by the Chairman of the Board, President. Vice Chairman of the
Board or a Vice President and the Secretary or an Assistant Secretary or the
Treasurer or an Assistant Treasurer of the Corporation representing the number
of shares (and, if the stock of the Corporation shall be divided into classes or
series, certifying the class and series of such shares) owned by such
shareholder which are registered in certified form; provided, however, that any
of or all the signatures on the certificate may be facsimile. The stock record
books and the blank stock certificate books shall be kept by the Secretary or at
the office of such transfer agent or transfer agents as the Board of Directors
may from time to time determine. In case any officer, transfer agent or
registrar who shall have signed or whose facsimile signature or signatures shall
have been placed upon any such certificate or certificates shall have ceased to
be such officer, transfer agent or registrar before such certificate is issued
by the Corporation, such certificate may nevertheless be issued by the
Corporation with the same effect as if such person were such officer, transfer
agent or registrar at the date of issue. The stock certificates shall be
consecutively numbered and shall be entered in the books of the Corporation as
they are issued and shall exhibit the holder's name and number of shares.

     SECTION 6.2.  TRANSFER OF SHARES. The shares of stock of the Corporation
shall be transferable only on the books of the Corporation by the holders
thereof in person or by their duly authorized attorneys or legal representatives
upon surrender and cancellation of certificates for a like number of shares.
Upon surrender to the Corporation or a transfer agent of the Corporation of a
certificate for shares duly endorsed or accompanied by proper evidence of
succession, assignment or authority to transfer, it shall be the duty of the
Corporation to issue a new certificate to the person entitled thereto, cancel
the old certificate and record the transaction upon its books.

     SECTION 6.3.  OWNERSHIP OF SHARES. The Corporation shall be entitled to
treat the holder of record of any share or shares of capital stock of the
Corporation as the holder in fact thereof and, accordingly, shall not be bound
to recognize any equitable or other claim to or interest in such share or shares
on the part of any other person, whether or not it shall have express or other
notice thereof, except as otherwise provided by the laws of the state of
incorporation of the Corporation.

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     SECTION 6.4.  REGULATIONS REGARDING CERTIFICATES. The Board of Directors
shall have the power and authority to make all such rules and regulations as
they may deem expedient concerning the issue, transfer and registration or the
replacement of certificates for shares of capital stock of the Corporation.

     SECTION 6.5.  LOST OR DESTROYED CERTIFICATES. The Board of Directors may
determine the conditions upon which the Corporation may issue a new certificate
of stock in place of a certificate theretofore issued by it which is alleged to
have been lost, stolen or destroyed and may require the owner of such
certificate or such owner's legal representative to give bond, with surety
sufficient to indemnify the Corporation and each transfer agent and registrar
against any and all losses or claims which may arise by reason of the alleged
loss, theft or destruction of any such certificate or the issuance of such new
certificate in the place of the one so lost, stolen or destroyed.

                                    ARTICLE 7
                            MISCELLANEOUS PROVISIONS

     SECTION 7.1.  FISCAL YEAR. The fiscal year of the Corporation shall begin
on the first day of January of each year.

     SECTION 7.2.  CORPORATE SEAL. The corporate seal shall be circular in form
and shall have inscribed thereon the name of the Corporation and the state of
its incorporation, which seal shall be in the charge of the Secretary and shall
be affixed to certificates of stock, debentures, bonds, and other documents, in
accordance with the direction of the Board of Directors or a committee thereof,
and as may be required by law; however, the Secretary may, if the Secretary
deems it expedient, have a facsimile of the corporate seal inscribed on any such
certificates of stock, debentures, bonds, contract or other documents.
Duplicates of the seal may be kept for use by any Assistant Secretary.

     SECTION 7.3.  NOTICE AND WAIVER OF NOTICE. Whenever any notice is required
to be given by law, the charter documents of the Corporation or under the
provisions of these Bylaws, said notice shall be deemed to be sufficient if
given (i) by telegraphic, cable or wireless transmission (including by telecopy
or facsimile transmission) or (ii) by deposit of the same in a post office box
or by delivery to an overnight courier service company in a sealed prepaid
wrapper addressed to the person entitled thereto at such person's post office
address, as it appears on the records of the Corporation, and such notice shall
be deemed to have been given on the day of such transmission or mailing or
delivery to courier, as the case may be.

     Whenever notice is required to be given by law, the charter documents of
the Corporation or under any of the provisions of these Bylaws, a written waiver
thereof, signed by the person entitled to notice, whether before or after the
time stated therein, shall be deemed equivalent to

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notice. Attendance of a person, including without limitation a director, at a
meeting shall constitute a waiver of notice of such meeting, except when the
person attends a meeting for the express purpose of objecting, at the beginning
of the meeting, to the transaction of any business because the meeting is not
lawfully called or convened. Neither the business to be transacted at, nor the
purpose of, any regular or special meeting of the shareholders, directors, or
members of a committee of directors need be specified in any written waiver of
notice unless so required by the charter documents of the Corporation or these
Bylaws.

     SECTION 7.4.  FACSIMILE SIGNATURES. In addition to the provisions for the
use of facsimile signatures elsewhere specifically authorized in these Bylaws,
facsimile signatures of any officer or officers of the Corporation may be used
whenever and as authorized by the Board of Directors.

     SECTION 7.5.  RELIANCE UPON BOOKS, REPORTS AND RECORDS. A member of the
Board of Directors, or a member of any committee designated by the Board of
Directors, shall, in the performance of such person's duties, be protected to
the fullest extent permitted by law in relying upon the records of the
Corporation and upon information, opinion, reports or statements presented to
the Corporation.

     SECTION 7.6.  APPLICATION OF BYLAWS. In the event that any provisions of
these Bylaws is or may be in conflict with any law of the United States, of the
state of incorporation of the Corporation or of any other governmental body or
power having jurisdiction over this Corporation, or over the subject matter to
which such provision of these Bylaws applies, or may apply, such provision of
these Bylaws shall be inoperative to the extent only that the operation thereof
unavoidably conflicts with such law, and shall in all other respects be in full
force and effect.

                                    ARTICLE 8
                    INDEMNIFICATION OF OFFICERS AND DIRECTORS

     SECTION 8.1.  INDEMNIFICATION. As permitted by Section G of Article 2.02-1
of the Texas Business Corporation Act or any successor statute (the
"Indemnification Article"), the Corporation hereby:

        (a) makes mandatory the indemnification permitted under Section B of the
Indemnification Article as contemplated by Section G thereof;

        (b) makes mandatory its payment or reimbursement of the reasonable
expenses incurred by a former or present director who was, is, or is threatened
to be made a named defendant or respondent in a proceeding upon such director's
compliance with the requirements of Section K of the Indemnification Article;
and

                                      -15-
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        (c) extends the mandatory indemnification referred to in Section 8.1(a)
above and the mandatory payment or reimbursement of expenses referred to in
Section 8.1(b) above (i) to all former or present officers of the Corporation
and (ii) to all persons who are or were serving at the request of the
Corporation as a director, officer, partner or trustee of another foreign or
domestic corporation, partnership, joint venture, trust or employee benefit
plan, to the same extent that the Corporation is obligated to indemnify and pay
or reimburse expenses to directors.

     SECTION 8.2.  NONEXCLUSIVITY. The indemnification provided by this Article
shall not be deemed exclusive of any other rights to which the person
indemnified may be entitled under any bylaw, agreement, authorization of
shareholders or disinterested directors or otherwise, both as to action in such
person's official capacity and as to action in another capacity while holding
such office, and shall continue as to a person who has ceased to be a director,
officer, employee or agent and shall enure to the benefit of such person's heirs
and legal representatives.

     SECTION 8.3.  INSURANCE. The Corporation shall have power to purchase and
maintain insurance on behalf of any person who is or was a director, officer,
employee, or agent of the Corporation or who is or was serving at the request of
the Corporation as a director, officer, partner, venturer, proprietor, trustee,
employee, agent or similar functionary of another business, foreign, domestic or
non-profit corporation, partnership, joint venture, sole proprietorship, trust
or other enterprise or employee benefit plan, against any liability asserted
against such person and incurred by such person in such a capacity or arising
out of such person's status as such a person, whether or not the Corporation
would have the power to indemnify such person against that liability under the
provisions of this Article or the Texas Business Corporation Act.

     SECTION 8.4.  WITNESSES. Notwithstanding any other provision of this
Article, the Corporation shall pay or reimburse expenses incurred by any
director, officer, employee or agent in connection with such person's appearance
as a witness or other participation in a proceeding at a time when such person
is not a named defendant or respondent in such proceeding.

                                    ARTICLE 9
                                   AMENDMENTS

     SECTION 9.1.  AMENDMENTS. The Board of Directors shall have the power to
adopt, amend and repeal from time to time Bylaws of the Corporation, subject to
the right of the shareholders entitled to vote with respect thereto to amend or
repeal such Bylaws as adopted or amended by the Board of Directors.

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