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                                                                    Exhibit 3.18

                                     BYLAWS

                                       OF

                            BONITA BAY HOLDINGS, INC.

                            (A Virginia Corporation)

                          (ADOPTED AS OF APRIL 6, 2004)

                                ARTICLE I OFFICE

The principal office of the Corporation in the Commonwealth of Virginia is at
526 King Street, Suite #423, Alexandria, Virginia.

                        ARTICLE II STOCKHOLDERS' MEETINGS

     Section 1.     ANNUAL MEETINGS. The annual meeting of the stockholders
of the Corporation, commencing with the 2004 shall be held at the principal
office of the Corporation in the Commonwealth of Virginia or at any other place
within or without the Commonwealth of Virginia as may be determined by the Board
of Directors and as may be designated in the notice of that meeting.

     An annual meeting of the stockholders shall be held each year within one
hundred twenty (120) days after the close of the immediately preceding fiscal
year of the Corporation for the purpose of electing directors and conducting
such other proper business as may come before the meeting. If the election of
directors shall not be held on the day herein designated for any annual meeting,
or at any adjournment of that meeting, the Board of Directors shall call a
special meeting of the stockholders as soon as possible thereafter. At this
meeting the election of directors shall take place, and the election and any
other business transacted shall have the same force and effect as at an annual
meeting duly called and held. No change in the time or place for a meeting for
the election of directors shall be made within 20 days preceding the day on
which the election is to be held. Written notice of any change shall be given
each stockholder at least 20 days before the election is held, either in person
or by letter mailed to the stockholder at the address last shown on the books of
the Corporation.

     In the event the annual meeting is not held at the time prescribed in
Article II, Section I, and if the Board of Directors shall not call a special
meeting as prescribed in Article II, Section I within three months after the
date prescribed for the annual meeting, then any stockholder may call that
meeting, and at that meeting the stockholders may elect the directors and
transact other business with the same force and effect as at an annual meeting
duly called and held.

     Section 2.     SPECIAL MEETINGS. Special meetings of the stockholders
may be called by the Chairman of the Board, the Board of Directors, the
President or by the holders of at least fifty percent (50%) of the stock
entitled to vote at that meeting. At any time, upon the written request of any
person or persons entitled to call a special meeting, it shall be the duty of
the Secretary to send out notices of the meeting, to be held within or without
the Commonwealth of Virginia and at such time, but not less than 10 days nor
more than 60 days after receipt of the request, as may

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be fixed by the Board of Directors. If the Board of Directors fails to fix a
time or place, the meeting shall be held at the principal office of the
Corporation at a time as shall be fixed by the Secretary within the above
limits.

     Section 3.     NOTICE AND PURPOSE OF MEETINGS; WAIVER. Each stockholder of
record entitled to vote at any meeting shall be given in person, or by mail, or
by prepaid telegram, written or printed notice of the purpose or purposes, and
the time and place within or outside the Commonwealth of Virginia of every
meeting of stockholders. This notice shall be delivered not less than 10 days
nor more than 60 days before the meeting. If mailed or telegraphed, it should be
directed to the stockholder at the address last shown on the books of the
Corporation. No publication of the notice of meeting shall be required. A
stockholder may waive the notice of meeting by attendance, either in person or
by proxy, at the meeting, or by so stating in writing, either before or after
the meeting. Attendance at a meeting for the express purpose of objecting that
the meeting was not lawfully called or convened shall not, however, constitute a
waiver of notice. Except where otherwise required by law, notice need not be
given of any adjourned meeting of the stockholders.

     Section 4.     QUORUM. Except as otherwise provided by law, a quorum at all
meetings of stockholders shall consist of the holders of record of a majority of
the shares entitled to vote present in person or by proxy.

     Section 5.     CLOSING OF TRANSFER BOOKS, - RECORD DATE. In order to
determine the holders of record of the Corporation's stock who are entitled to
notice of meetings, to vote at a meeting or its adjournment, to receive payment
of any dividend, or to make a determination of the stockholders of record for
any other proper purpose, the Board of Directors of the Corporation may order
that the Stock Transfer Books be closed for a period not to exceed seventy days.
If the purpose of this closing is to determine who is entitled to notice of a
meeting and to vote at such meeting, the Stock Transfer Books shall be closed
for at least thirty days preceding such meeting.

     In lieu of closing the Stock Transfer Books, the Board of Directors may fix
a date as the record date for the determination of stockholders. This date shall
be no more than sixty days prior to the date of the action which requires the
determination, nor, in the case of a stockholders' meeting, shall it be less
than thirty days in advance of such meeting.

     If the Stock Transfer Books are not closed and no record date is fixed for
the determination of the stockholders of record, the date of which notice of the
meeting is mailed, or on which the resolution of the Board of Directors
declaring a dividend is adopted, as the case may be, shall be the record date
for the determination of stockholders.

     When a determination of stockholders entitled to vote at any meeting has
been made as provided in this section, this determination shall apply to any
adjournment of the meeting, except when the determination has been made by the
closing of the Stock Transfer Books and the stated period of closing has
expired.

     Section 6.     PRESIDING OFFICER; ORDER OF BUSINESS. Meetings of the
stockholders shall be presided over by the Chairman of the Board, or, if he or
she is not present, by the Chief

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Executive Officer, or if not present, by the President, or if he or she is not
present, by a Vice-President, or if neither the Chairman of the Board nor the
Chief Executive Officer nor the President nor a Vice-President is present, by a
chairman to be chosen by a majority of the stockholders entitled to vote at the
meeting who are present in person or by proxy. The Secretary of the Corporation,
or, in her or his absence, an Assistant Secretary, shall act as secretary of
every meeting, but if neither the Secretary nor an Assistant Secretary is
present, the stockholders present at the meeting shall choose any person present
to act as secretary of the meeting.

     Section 7.     VOTING. Except in the election of directors, at which time
the stockholders shall be entitled to cumulate their votes if provided for in
the Articles of Incorporation, and except as otherwise provided in the Articles
of Incorporation, the Bylaws, or the laws of the Commonwealth of Virginia at
every meeting of the stockholders, each stockholder of the Corporation entitled
to vote at the meeting shall have, as to each matter submitted to a vote, one
vote in person or by proxy for each share of stock having voting rights
registered in his or her name on the books of the Corporation. A stockholder may
vote his or her shares through a proxy appointed by a written instrument signed
by the stockholder or by a duly authorized attorney-in-fact and delivered to the
secretary of the meeting. No proxy shall be valid after three months from the
date of its execution unless a longer period is expressly provided. A majority
vote of those shares entitled to vote and represented at the meeting, a quorum
being present, shall be the act of the meeting except that in electing directors
a plurality of the votes cast shall elect. At all elections of directors, the
voting shall be by ballot.

     Section 8.     LIST OF STOCKHOLDERS. A complete list of the stockholders of
the Corporation entitled to vote at the ensuing meeting, arranged in
alphabetical order, and showing the address of, and number of shares owned by,
each stockholder shall be prepared by the Secretary, or other officer of the
Corporation having charge of the Stock Transfer Books. This list shall be kept
on file for a period of at least ten days prior to the meeting at the principal
office of the Corporation and shall be subject to inspection during the usual
business hours of such period by any stockholder. This list shall also be
available at the meeting and shall be open to inspection by any stockholder at
any time during the meeting. The original Stock Transfer Books shall be prima
facie evidence as to who are the stockholders entitled to examine the list or to
vote at any meeting of the stockholders. Failure to comply with the requirements
of this section shall not affect the validity of any action taken at any
meetings of the stockholders.

                              ARTICLE III    DIRECTORS

     Section 1.     NUMBER, QUALIFICATION, TERM, QUORUM, AND VACANCIES. The
property, affairs and business of the Corporation shall be managed by a Board of
Directors. The initial number of members of the Board of Directors shall be set
at two members. Except as provided, directors shall be elected at the annual
meeting of the stockholders and each director shall serve for one year and/or
until his or her successor shall be elected and qualify. The number of directors
may be increased or decreased from time to time by an amendment to these Bylaws.
Any increased number of directors shall be elected by the stockholders at the
next regular annual meeting or at a special meeting called for that purpose. The
number of directors shall never be less than one. Directors need not be
stockholders of the Corporation.

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     A majority of the directors in office shall be necessary to constitute a
quorum for the transaction of business. If, at any meeting of the Board of
Directors, there shall be less than a quorum present, a majority of those
present may adjourn the meeting, without further notice, from time to time until
a quorum shall have been obtained. In case there are vacancies on the Board of
Directors, other than vacancies created by the removal of a director or
directors by the stockholders or by an increase in the number of directors, the
remaining directors, although less than a quorum, may by a majority vote elect a
successor or successors for the unexpired term or terms.

     Section 2.     MEETINGS. Meetings of the Board of Directors may be held
either within or without the Commonwealth of Virginia. Meetings of the Board of
Directors shall be held at those times as are fixed from time to time by
resolution of the Board. Special meetings may be held at any time upon call of
the Chairman of the Board, the Chief Executive Officer, the President, or a
Vice-President, or a majority of directors, upon written or telegraphic notice
deposited in the U.S. mail or delivered to the telegraph company at least thirty
days prior to the day of the meetings. A meeting of the Board of Directors may
be held without notice immediately following the annual meeting of the
stockholders. Notice need not be given of regular meetings of the Board of
Directors held at times fixed by resolution of the Board of Directors nor need
notice be given of adjourned meetings. Meetings may be held at any time without
notice if all the directors are present or if, before the meeting, those not
present waive such notice in writing. Notice of a meeting of the Board of
Directors need not Commonwealth the purpose of, nor the business to be
transacted at, any meeting.

     Section 3.     REMOVAL. At any meeting of the stockholders, any director or
directors may be removed from office, without assignment of any reason, by a
majority vote of the shares or class of shares, as the case may be, which
elected the director or directors to be removed, provided, however, that if less
than all the directors are to be removed, no individual director shall be
removed if the number of votes cast against her or his removal would be
sufficient, if cumulatively voted at an election of the entire board, to elect
one or more directors.

     When any director or directors are removed, new directors may be elected at
the same meeting of the stockholders for the unexpired term of the director or
directors removed. If the stockholders fail to elect persons to fill the
unexpired term or terms of the director or directors removed, these unexpired
terms shall be considered vacancies on the board to be filled by the remaining
directors.

     Section 4.     INDEMNIFICATION. The Corporation shall indemnify each of its
directors, officers, and employees whether or not then in service as such (and
his or her executor, administrator and heirs), against all reasonable expenses
actually and necessarily incurred by him or her in connection with the defense
of any litigation to which the individual may have been made a party because he
or she is or was a director, officer or employee of the Corporation. The
individual shall have no right to reimbursement, however, in relation to matters
as to which he or she has been adjudged liable to the Corporation for negligence
or misconduct in the performance of his or her duties, or was derelict in the
performance of his or her duty as director, officer or employee by reason of
willful misconduct, bad faith, gross negligence or reckless disregard of the
duties of his or her office or employment. The right to indemnity for expenses
shall also apply to the expenses of suits which are compromised or settled if
the court having jurisdiction

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of the matter shall approve such settlement. The foregoing right of
indemnification shall be in addition to, and not exclusive of, all other rights
to that which such director, officer or employee may be entitled.

     Section 5.     COMPENSATION. Directors, and members of any committee of the
Board of Directors, shall be entitled to any reasonable compensation for their
services as directors and members of any committee as shall be fixed from time
to time by resolution of the Board of Directors, and shall also be entitled to
reimbursement for any reasonable expense incurred in attending those meetings.
The compensation of directors may be on any basis as determined in the
resolution of the Board of Directors. Any director receiving compensation under
these provisions shall not be barred from serving the Corporation in any other
capacity and receiving reasonable compensation for such other services.

     Section 6.     COMMITTEES. The Board of Directors, by a resolution or
resolutions adopted by a majority of the members of the whole Board, may appoint
an Executive Committee, an Audit Committee, and any other committees as it may
deem appropriate. Each committee shall consist of at least three members of the
Board of Directors. Each committee shall have and may exercise any and all
powers as are conferred or authorized by the resolution appointing it. A
majority of each committee may determine its action and may fix the time and
place of its meetings, unless provided otherwise by the Board of Directors. The
Board of Directors shall have the power at any time to fill vacancies in, to
change the size of membership of, and to discharge any committee. Each committee
shall keep a written record of its acts and proceedings and shall submit that
record to the Board of Directors at each regular meeting and at any other times
as requested by the Board of Directors. Failure to submit the record, or failure
of the Board to approve any action indicated therein will not, however,
invalidate the action to the extent it has been carried out by the Corporation
prior to the time the record of such action was, or should have been, submitted
to the Board of Directors as provided.

     Section 7.     DIVIDENDS. Subject always to the provisions of law and the
Articles of Incorporation, the Board of Directors shall have full power to
determine whether any, and, if so, what part, of the funds legally available for
the payment of dividends shall be declared in dividends and paid to the
stockholders of the Corporation. The Board of Directors may fix a sum which may
be set aside or reserved over and above the paid-in capital of the Corporation
for working capital or as a reserve for any proper purpose, and from time to
time may increase, diminish, and vary this fund in the Board's absolute judgment
and discretion.

                               ARTICLE IV OFFICERS

     Section 1.     NUMBER. The officers of the Corporation shall be a Chairman
of the Board, a Chief Executive Officer, a President, one or more
Vice-Presidents, a Treasurer, a Controller, a Secretary, and one or more
Assistant Secretaries. In addition, there may be such subordinate officers as
the Board of Directors may deem necessary. Any person may hold two, but no more
than two, offices.

     Section 2.     TERM OF OFFICE. The principal officers shall be chosen
annually by the Board of Directors at the first meeting of the Board following
the stockholders' annual meeting, or as soon as is conveniently possible.
Subordinate officers may be elected from time to time.

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Each officer shall serve until his or her successor shall have been chosen and
qualified, or until his, death, resignation, or removal.

     Section 3.     REMOVAL. Any officer may be removed from office with or
without cause, at any time by the affirmative vote of a majority of the Board of
Directors then in office. Such removal shall not prejudice the contract rights,
if any, of the person so removed.

     Section 4.     VACANCIES. Any vacancy in any office from any cause may be
filled for the unexpired portion of the term by the Board of Directors.

     Section 5.     DUTIES. The Chairman of the Board shall preside at all
meetings of the stockholders and the Board of Directors. Except where, by law,
the signature of the President is required, the Chairman shall possess the same
power as the President to sign all certificates, contracts, and other
instruments of the Corporation which may be authorized by the Board of
Directors.

     The Chief Executive Officer shall have general active management of the
business of the corporation, and in the absence of the Chairman of the Board,
shall preside at all meetings of the shareholders and the Board of Directors;
and shall see that all orders and resolutions of the Board of Directors are
carried into effect.

     The President, in the absence of the Chairman of the Board, shall preside
at all meetings of the stockholders and the Board of Directors. She or he shall
have general supervision of the affairs of the Corporation, shall sign or
countersign all certificates, contracts, or other instruments of the Corporation
as authorized by the Board of Directors, shall make reports to the Board of
Directors and stockholders, and shall perform any and all other duties as are
incident to her or his office or are properly required of him or her by the
Board of Directors.

     The Vice-Presidents, in the order designated by the Board of Directors,
shall exercise the functions of the President during the absence or disability
of the President. Each Vice-President shall have any other duties as are
assigned from time to time by the Board of Directors.

     The Secretary, the Treasurer, and the Controller shall perform those duties
as are incident to their offices, or are properly required of them by the Board
of Directors, or are assigned to them by the Articles of Incorporation or these
Bylaws. The Assistant Secretaries, in the order of their seniority, shall, in
the absence of the Secretary, perform the duties and exercise the powers of the
Secretary, and shall perform any other duties as may be assigned by the Board of
Directors.

     Other subordinate officers appointed by the Board of Directors shall
exercise any powers and perform any duties as may be delegated to them by the
resolutions appointing them, or by subsequent resolutions adopted from time to
time.

     In case of the absence or disability of any officer of the Corporation and
of any person authorized to act in his or her place during such period of
absence or disability, the Board of Directors may from time to time delegate the
powers and duties of that officer to any other officer, or any director, or any
other person whom it may select.

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     Section 6.     SALARIES. The salaries of all officers of the Corporation
shall be fixed by the Board of Directors. No officer shall be ineligible to
receive such salary by reason of the fact that he is also a Director of the
Corporation and receiving compensation therefor.

                         ARTICLE V CERTIFICATES OF STOCK

     Section 1.     FORM. The interest of each stockholder of the Corporation
shall be evidenced by certificates for shares of stock, certifying the number of
shares represented thereby and in such form not inconsistent with the Articles
of Incorporation as the Board of Directors may from time to time prescribe. The
certificates of stock shall be signed by the President or a Vice-President and
by the Secretary or an Assistant Secretary or the Treasurer, and sealed with the
seal of the corporation. This seal may be a facsimile, engraved or printed.
Where any certificate is manually signed by a transfer agent or a transfer clerk
and by a registrar, the signatures of the President, Vice-President, Secretary,
Assistant Secretary, or Treasurer upon that certificate may be facsimiles,
engraved or printed. In case any officer who has signed or whose facsimile
signature has been placed upon any certificate shall have ceased to be an
officer before the certificate is issued, it may be issued by the corporation
with the same effect as if that officer had not ceased to be so at the time of
its issue.

     Section 2.     SUBSCRIPTIONS FOR SHARES. Unless the subscription agreement
provides otherwise, subscriptions for shares, regardless of the time when they
are made, shall be paid in full at that time, or in installments and at any
periods, as shall be specified by the Board of Directors. All calls for payments
on subscriptions shall carry the same terms with regard to all shares of the
time class.

     Section 3.     TRANSFERS. Transfers of shares of the capital stock of the
Corporation shall be made only on the books of the Corporation by the registered
owner, or by his or her duly authorized attorney, with a transfer clerk or
transfer agent appointed as provided in Section 5 of this Article of the Bylaws,
and on surrender of the certificate or certificates for those shares properly
endorsed with all taxes paid.

     The person in whose name shares of stock stand on the books of the
Corporation shall be deemed by the Corporation to be the owner thereof for all
purposes. However, if any transfer of shares is made only for the purpose of
furnishing collateral security, and that fact is made known to the Secretary of
the Corporation, or to the Corporation's transfer clerk or transfer agent, the
entry of the transfer may record that fact.

     Section 4.     LOST, DESTROYED, OR STOLEN CERTIFICATES. No certificate for
shares of stock in the Corporation shall be issued in place of any certificate
alleged to have been lost, destroyed, or stolen except on production of
evidence, satisfactory to the Board of Directors, of that loss, destruction or
theft, and, if the Board of Directors so requires, upon the furnishing of an
indemnity bond in such amount (but not to exceed twice the value of the shares
represented by the certificate) and with such terms and surety as the Board of
Directors, if any, in its discretion, require.

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     Section 5.     TRANSFER AGENT AND REGISTRAR. The Board of Directors may
appoint one or more transfer agents or transfer clerks and one or more
registrars, and may require all certificates for shares to bear the signature or
signatures of any of them.

                          ARTICLE VI   CORPORATE ACTIONS

     Section 1.     DEPOSITS. The Board of Directors shall select banks, trust
companies, or other depositories in which all funds of the Corporation not
otherwise employed shall, from time to time, be deposited to the credit of the
Corporation.

     Section 2.     VOTING SECURITIES HELD BY THE CORPORATION. Unless otherwise
ordered by the Board of Directors, the President shall have full power and
authority on behalf of the Corporation to attend, act, and vote at any meeting
of security holders of other corporations in which the Corporation may hold
securities. At that meeting the President shall possess and may exercise any and
all rights and powers incident to the ownership of those securities which the
corporation might have possessed and exercised if it had been present. The Board
of Directors may, from time to time, confer like powers upon any other person or
persons.

                           ARTICLE VII    CORPORATE SEAL

     The corporate seal of the Corporation shall consist of two concentric
circles, between which shall be the name of the Corporation, and in the center
of which shall be inscribed the year of its incorporation and the words
"Corporate Seal, Commonwealth of Virginia.

                        ARTICLE VIII   AMENDMENT OF BYLAWS

     The Board of Directors shall have the power to amend, alter or repeal these
Bylaws, and to adopt new Bylaws, from time to time, by an affirmative vote of a
majority of the whole Board as then constituted, provided that notice of the
proposal to make, alter, amend, or repeal the Bylaws was included in the notice
of the directors' meeting at which such action takes place. At the next
stockholders' meeting following any action by the Board of Directors, the
stockholders, by a majority vote of those present and entitled to vote, shall
have the power to alter or repeal Bylaws newly adopted by the Board of
Directors, or to restore to their original status Bylaws which the Board may
have altered or repealed, and the notice of such stockholders' meeting shall
include notice that the stockholders will be called on to ratify the action
taken by the Board of Directors with regard to the Bylaws.

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