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                                                                   EXHIBIT 3.22


                                    BYLAWS OF
                              DANIEL & YEAGER, INC.

                                    ARTICLE I

                                 IDENTIFICATION

         (1) NAME: The name of the corporation is Daniel & Yeager, Inc.
("Corporation").

         (2) PRINCIPAL OFFICE: The address of the principal office of the
Corporation is 7220 Governors Drive, W., Huntsville, Alabama 35806. The
Corporation may have such other offices either within or without the State of
Alabama as the board of directors may designate or as the business of the
Corporation may from time to time require.

                                   ARTICLE 11

                            MEETINGS OF SHAREHOLDERS

         (1) ANNUAL MEETING: The annual meeting of the shareholders of the
Corporation shall be held on the second Tuesday of the third month following the
end of the Corporation's fiscal year, if not a legal holiday, and if a legal
holiday, then on the next day following, or such other date as may be prescribed
by the board of directors, for the purposes of:

                  (a) electing directors;

                  (b) considering and acting upon the reports of officers and
         directors; and

                  (c) transacting such other business as may come before the
         meeting.

         (2) SPECIAL MEETINGS: Special meetings of the shareholders may be held
at any time whenever called by the president, by the board of directors, or by
any shareholder.

         (3) NOTICE: Written notice of all meetings shall be given to each
shareholder at his address as it appears on the stock transfer books of the
Corporation. Notices shall specify the purpose, place, day, and hour of the
meeting. Notice shall be given not less than ten nor more than fifty days before
the meeting.

         (4) WAIVER: Any shareholder may waive notice of any meeting of the
shareholders by a written waiver of notice signed by such shareholder before,
at, or after such meeting.

         (5) PROXY: At any meeting of the shareholders a shareholder may vote
either in person or by written proxy. No proxy shall be valid after eleven
months from the date of its execution, unless otherwise provided in the proxy.

         (6) QUORUM: For the transaction of business at any meeting of the
shareholders, the holders of more than fifty percent of the shares must be
present in person or by proxy, except as
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otherwise provided by law. If, however, such majority shall not be present at
any meeting of the shareholders, the shareholders present shall have power to
adjourn the meeting, without notice other than announcement at the meeting,
until the requisite number of shares shall be present. If the requisite number
of shares shall become represented at such adjourned meeting, any business may
then be transacted which might have been transacted at the meeting as originally
called.

         (7) VOTING: All questions and elections shall be determined by a
majority vote of the shares present at any meeting, except as otherwise provided
by law. Only persons in whose names shares appear on the stock transfer books of
the Corporation on the date on which notice of the meeting is given shall be
entitled to vote at such meeting, unless some other day is fixed by the board of
directors for the determination of shareholders of record. Such date shall be
not less than ten days nor more than fifty days before the meeting. Each
outstanding share shall be entitled to one vote on each matter submitted to a
vote.

         (8) PLACE: The board of directors may designate any place either within
or without the State of Alabama as the place of meeting for any annual or
special meeting of the shareholders. In the absence of any designation, all
meetings shall be held at the principal office of the Corporation.

         (9) CONSENT: Any action which may be taken by the shareholders at a
meeting may be taken without a meeting if a written consent setting forth the
action so taken is signed by all of the shareholders. Such a consent shall have
the effect of a unanimous vote, and the signature of a shareholder thereon shall
constitute a waiver of notice under Paragraph (4) above.

         (10) VOTING RECORD: At least ten days before each meeting of the
shareholders, the secretary shall make a complete list of the shareholders
entitled to vote at such meeting. Such list shall be prepared in alphabetical
order and shall show the address and number of shares held by each shareholder.
The list shall be kept on file at the principal office of the Corporation and
shall be subject to inspection at any time during normal business hours by any
shareholder making written request therefor. The list shall be produced and kept
open at the time and place of the meeting and shall be subject to inspection by
any shareholder during the meeting.

                                   ARTICLE III
                             THE BOARD OF DIRECTORS

         (1) NUMBER AND QUALIFICATIONS: The board of directors of the
Corporation shall consist of not less than one nor more than seven directors to
be elected by the shareholders. No director need be a shareholder or a resident
of Alabama.


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         (2) TERM: A director's term of office shall be for the twelve-month
period following his election and until his successor is elected and qualified,
or until his earlier death.

         (3) VACANCY: The remaining directors, even if not constituting a
quorum, shall elect a director to fill any vacancy caused by death or by an
increase in the number of directorships.

         (4) REMOVAL: Any director may be removed with or without cause by vote
of the shareholders at any meeting called for that purpose; and the shareholders
may immediately upon such removal elect a successor to fill such director's
unexpired term.

         (5) POWERS: The board of directors shall have the entire management of
the Corporation and is vested with all the powers possessed by the Corporation
itself. The board of directors shall have the power to determine what
constitutes net income, earnings, and surplus, what amounts shall be reserved
for working capital and for other purposes, and what amount shall be declared as
dividends. Such determinations by the board of directors shall be final and
conclusive.

         (6) REGULAR MEETING: A regular meeting of the board of directors shall
be held immediately following the annual meeting of the shareholders.

         (7) SPECIAL MEETINGS: Special meetings of the board of directors may be
called by the president or by any two directors.

         (8) NOTICE: Meetings of the board of directors shall be called on no
less than three-days advance written notice to each director, at his address,
specifying the purpose, place, day, and hour of such meeting. Meetings may be
held by conference telephone call or by like means in accordance with Title 10,
Chapter 2A, Code of Alabama (11975), as amended ("Alabama Business Corporation
Act").

         (9) WAIVER: Any director may waive notice of any meeting of the board
of directors by written waiver of notice signed by such director before, at, or
after such meeting. Attendance of a director at a meeting shall constitute a
waiver of notice of such meeting.

         (10) QUORUM: A quorum shall consist of a majority of the directors.

         (11) VOTING: All questions and elections shall be determined by a
majority vote of the directors in attendance at any meeting, except as may
otherwise be provided by law.

         (12) CONSENT: Any action which may be taken by the board of directors
at a meeting may be taken without a meeting if a written consent setting forth
the action so taken is signed by all of the directors. Such a consent shall have
the effect of a unanimous vote, and the signature of a director thereon shall
constitute a waiver of notice under Paragraph (9) of this article.


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         (13) COMPENSATION: Directors and members of committees may receive such
compensation, if any, for their services and such reimbursement for expenses as
may be fixed or determined by resolution of the board of directors.

                                   ARTICLE IV
                                  THE OFFICERS

         (1) OFFICERS: The officers of the corporation shall be elected by the
board of directors and shall consist of a president, a vice-president, a
secretary, and a treasurer, or a secretary-treasurer. The board of directors may
also elect additional vice-presidents, assistant secretaries, and assistant
treasurers.

         (2) ELECTION: At its regular meeting after an annual meeting of the
shareholders, the board of directors shall elect a president, a vice-president,
a secretary, and a treasurer, or a secretary-treasurer, and such other officers
as shall be deemed appropriate. One person may hold more than one office.

         (3) OTHER AGENTS: The board of directors may elect and employ such
other officers, agents and/or employees as it shall deem appropriate. Such
officers, agents and/or employees shall exercise such powers and perform such
duties as shall be fixed by the board of directors.

         (4) COMPENSATION: The salaries and other compensation of all officers,
agents, and employees of the Corporation shall be fixed by the board of
directors.

         (5) TERM OF OFFICE: The term of office for an officer shall be the
twelve-month period following election and until a successor is duly elected and
qualified or until his earlier death. Any vacancy occurring in any office of the
Corporation shall be filled by the board of directors by electing a successor to
serve for the remaining portion of the above-mentioned twelve-month period.

         (6) REMOVAL: Any officer elected by the board of directors may be
removed at any time with or without cause by vote of the board of directors.

         (7) DUTIES: Each officer shall have the duties usual and customary to
his office, including but not limited to the following:

                  (a) PRESIDENT: The president shall be the chief executive
officer of the Corporation. He shall preside at all meetings of the shareholders
and directors and shall have the general supervision and management of the
business of the Corporation. The president shall see that all orders and
resolutions are carried into effect. The president shall have authority to
execute


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instruments and documents on behalf of the Corporation in the ordinary
course of business, and on such instruments and documents the seal of the
Corporation may be affixed and attested by the secretary of the Corporation.

                  (b) VICE-PRESIDENT: The vice-president shall perform those
duties assigned to him by the board of directors and shall, in the absence or
disability of the president, perform the duties and exercise the powers of the
president. However, the vice-president shall not have the power to execute
instruments and documents on behalf of the Corporation, except upon resolution
of the board of directors.

                  (c) SECRETARY: The secretary shall attend all meetings of the
board of directors and meetings of the shareholders, and shall record all votes
and minutes of all meetings in a book to be kept for that purpose. He shall give
notice of all shareholder's meetings to the shareholders and of all meetings of
the board of directors to the directors. He shall be custodian of the corporate
seal of the Corporation and shall affix the corporate seal to any instrument
requiring it, attesting the same by his signature. The secretary shall keep and
maintain the Corporation's stock transfer book, including a stock register,
showing the number of shares issued to all shareholders, and the date of any
issuance, transfer, or cancellation of same.

                  (d) TREASURER: The treasurer shall have custody of the
Corporation's funds and securities and shall keep full and accurate accounts of
receipts and disbursements in books belonging to the Corporation. The treasurer
shall deposit all monies and all valuable effects in the name of the Corporation
in such depositories as may be designated by the board of directors, except such
petty cash funds as may be provided by the board of directors. Such funds so
deposited shall be subject to withdrawal on checks signed by the treasurer or by
such other person as the board of directors may designate.

                                    ARTICLE V
                                   AMENDMENTS

         These bylaws may be amended or repealed and new bylaws may be adopted
by the board of directors at any regular meeting of the board of directors or at
a special meeting of the directors called for such purpose; provided, however,
that a majority of the shareholders may amend, repeal or adopt new bylaws at any
regular meeting of the shareholders or at a special meeting of the shareholders
called for that purpose.

                                   ARTICLE VI
                                     SHARES


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         (1) CERTIFICATES FOR SHARES: Each shareholder of the Corporation shall
be entitled to have a certificate signed in the name of the Corporation by the
president or vice-president and the secretary or treasurer, certifying the
number of shares owned by him.

         (2) TRANSFER OF SHARES: Upon surrender to the secretary of a
certificate for shares duly endorsed or accompanied by proper evidence of
succession, assignment, or authority to transfer, the secretary shall issue a
new certificate to the person entitled thereto, cancel the old certificate, and
record the transaction upon the Corporation's books -- subject, however, to any
agreement of the shareholders and the Corporation restricting the right to
transfer shares.

         (3) SHAREHOLDER'S RIGHTS: The Corporation shall be entitled to
recognize the exclusive right of a person registered on its books as the owner
of shares to receive dividends and to vote as such owner. The Corporation shall
not be bound to recognize any equitable or other claim to or interest in such
shares on the part of any other person, whether or not it shall have notice or
knowledge thereof, except as otherwise provided by law.

         (4) COMMON SHARES: The shares of the Corporation shall be common
shares. Except as stated in the articles of incorporation or herein, such shares
have all of the powers granted by the laws of the State of Alabama to shares of
that nature.

         (5) ASSESSMENT: When fully paid for, the shares of the Corporation
shall not be assessable.

         (6) LIEN FOR INDEBTEDNESS: The Corporation shall have a lien on the
shares of any holder for any indebtedness of the holder to the Corporation.

         (7) LOST CERTIFICATES: Any person claiming that a certificate for
shares has been lost, stolen, or destroyed shall make an affidavit or
affirmation of that fact and advertise the same in such manner as the board of
directors may require and shall give the Corporation such bond or
indemnification in such amount and form and with such sureties as may be
required by the board of directors, whereupon a new certificate may be issued of
the same tenor and for the same number of shares as the one alleged to have been
lost or destroyed.

                                   ARTICLE VII
                                    DIVIDENDS

         Dividends shall be declared and paid out of the unrestricted and
unreserved earned surplus of the Corporation as often and at such times as the
board of directors may determine in accordance with the Alabama Business
Corporation Act. Such dividends shall be declared and paid at such times as not
to curtail the effective operation of the business. Before payment of any


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dividend the board of directors may set aside out of the earned surplus of the
Corporation such sum as the board of directors may, in its discretion, deem
proper as a reserve fund for meeting contingencies, for equalizing dividends,
for repairing or maintaining any property of the Corporation, or for any other
purposes the board of directors shall deem conducive to the interests of the
Corporation.

                                  ARTICLE VIII
                                     NOTICES

         Whenever the provisions of these bylaws or the laws of the State of
Alabama require notice to be given to any director or shareholder, notice shall
be given by personal delivery or by depositing the same in the United States
mail, postage prepaid, addressed to such shareholder or director at his address
as it appears in the minute book or stock transfer records of the Corporation.
Any director or shareholder may waive any notice required to be given by law,
the articles of incorporation, or these bylaws.

                                   ARTICLE IX
                                   FISCAL YEAR

         The first fiscal year of the Corporation shall begin on the formation
of the Corporation and shall end on such day as may be selected by the board of
directors; and each subsequent fiscal year shall conform to the fiscal year
adopted for purposes of reporting under the Internal Revenue Code of 1986, as
amended.

                                    ARTICLE X
                          RECORDS AND FINANCIAL REPORTS

         (1) MINUTE BOOK: The secretary shall keep and maintain a minute book
containing the articles of incorporation, bylaws, minutes of the meetings of the
shareholders, directors, and committees, the stock transfer books, and other
pertinent records of the Corporation.

         (2) RECORDS OF TRANSACTIONS: The secretary shall maintain at the
principal office of the Corporation correct and complete records of all
transactions of the Corporation and the minute book, or copies thereof.

         (3) FINANCIAL STATEMENT: The board of directors shall direct the
treasurer to mail to each of the shareholders such financial information as may
be required by the laws of the State of Alabama.

                                   ARTICLE XI
                                 CORPORATE SEAL


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         The corporate seal shall have inscribed thereon the name of the
Corporation and the words "Corporate Seal, Alabama." The seal may be used by
causing it or a facsimile thereof to be impressed or otherwise affixed.


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         DATED this the 26th day of October, 1989

         ATTEST:

                                              /s/ Samuel C. Yeager
                                              ____________________________
                                              Samuel C. Yeager
                                              As Its President

         /s/ John S. Daniel
         ____________________________
         John S. Daniel
         As Its Secretary

                          THIS INSTRUMENT PREPARED BY:
                          BRADLEY, ARANT, ROSE & WHITE
                               By: Scott E. Ludwig
                              223 East Side Square
                            Huntsville, Alabama 35801
                            Telephone (205) 533-5040


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