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                                                                   EXHIBIT 10.15

                          CAC IV SPECIAL GENERAL, INC.

                                     BYLAWS
                               AS OF JUNE 7, 2001


                                    ARTICLE I
                            MEETINGS OF SHAREHOLDERS

     1.1 Place and Time of Meetings. Meetings of shareholders shall be held at
such place, either within or without the Commonwealth of Virginia, and at such
time, as may be provided in the notice of the meeting and approved by the
President or the Board of Directors.

     1.2 Annual Meeting. The annual meeting of shareholders, shall be held on
the second Tuesday in August of each year, or on such date, as may be designated
by resolution of the Board of Directors from time to time for the purpose of
electing directors and conducting such other business as may properly come
before the meeting.

     1.3 Special Meetings. Special meetings of the shareholders may be called by
the President or the Board of Directors and shall be called by the Secretary
upon demand of shareholders as required by law. Only business within the purpose
or purposes described in the notice for a special meeting of shareholders may be
conducted at the meeting.

     1.4 Record Dates. The Board of Directors may fix, in advance, a record date
to make a determination of shareholders entitled to notice of, or to vote at,
any meeting of shareholders, to receive any dividend or for any purpose, such
date to be not more than seventy (70) days before the meeting or action
requiring a determination of shareholders. If no such record date is set then
the record date shall be the close of business on the day before the date on
which the first notice is given.

     When a determination of shareholders entitled to notice of, or to vote at,
any meeting of shareholders has been made, such determination shall be effective
for any adjournment of the meeting unless the Board of Directors fixes a new
record date, which it shall do if the meeting is adjourned to a date more than
one hundred twenty (120) days after the date fixed for the original meeting.

     1.5 Notice of Meetings. Written notice stating the place, day and hour of
each meeting of shareholders and, in case of a special meeting, the purpose or
purposes for which the

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meeting is called, shall be given not less than ten (10) nor more than sixty
(60) days before the date of the meeting (except when a different time is
required in these Bylaws or by law) either personally or by mail, courier,
facsimile, email, or other form of wire or wireless communication, to each
shareholder of record entitled to vote at such meeting. Each such notice shall
be deemed effective on: (a) the fifth (5/th/) business day after being mailed by
United States certified mail, return receipt requested, postage prepaid; (b) the
day when delivered by hand; (c) the first business day after being deposited
with a national overnight courier; or (d) the day when transmitted by facsimile
or email with confirmation of receipt or successful transmission.

     If a meeting is adjourned to a different date, time or place, notice need
not be given if the new date, time or place is announced at the meeting before
adjournment. However, if a new record date for an adjourned meeting is fixed,
notice of the adjourned meeting shall be given to shareholders as of the new
record date, unless a court of competent jurisdiction provides otherwise.

     1.6 Waiver of Notice. A shareholder may waive any notice required by law,
the Articles of Incorporation or these Bylaws before or after the date and time
of the meeting that is the subject of such notice. The waiver shall be in
writing, be signed by the shareholder entitled to the notice, and be delivered
to the Secretary of the Corporation for inclusion in the minutes or filing with
the corporate records.

     A shareholder who attends a meeting waives any objection (a) to lack of
notice or defective notice of the meeting, unless the shareholder at the
beginning of the meeting objects to holding the meeting or transacting business
at the meeting, and (b) to consideration of a particular matter at the meeting
that is not within the purpose or purposes described in the meeting notice,
unless the shareholder objects to considering the matter when it is presented.

     1.7 Quorum and Voting Requirements. Unless otherwise required by law, a
majority of the votes entitled to be cast on a matter constitutes a quorum for
action on that matter. Once a share is represented for any purpose at a meeting,
it is deemed present for quorum purposes for the remainder of the meeting and
for any adjournment of that meeting unless a new record date is or shall be set
for that adjourned meeting. If a quorum exists, action on a matter, other than
the election of directors, is approved if the votes cast favoring the action
exceed the votes cast opposing the action, unless a greater number of
affirmative votes is required by law. Directors shall be elected by a plurality
of the votes cast by the shares entitled

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to vote in the election at a meeting at which a quorum is present. Less than a
quorum may adjourn a meeting.

     1.8 Action Without Meeting. Action required or permitted to be taken at a
meeting of the shareholders may be taken without a meeting and without action by
the Board of Directors if the action is taken by all the shareholders entitled
to vote on the action. The action shall be evidenced by one or more written
consents describing the action taken, signed by all the shareholders and
delivered to the Secretary of the Corporation for inclusion in the minutes or
filing with the corporate records. Action taken by unanimous consent shall be
effective according to its terms when all consents are in the possession of the
Corporation, unless the consent specifies a different effective date, in which
event the action taken shall be effective as of the date specified therein
provided that the consent states the date of execution by each shareholder. A
shareholder may withdraw a consent only by delivering a written notice of
withdrawal to the Corporation prior to the time that all consents are in the
possession of the Corporation.

     If not otherwise fixed pursuant to the provisions of Section, the record
date for determining shareholders entitled to take action without a meeting is
the date the first shareholder signs the consent described in the preceding
paragraph.

                                   ARTICLE II
                                    DIRECTORS

     2.1 General Powers. The Corporation shall have a Board of Directors. All
corporate powers shall be exercised by or under the authority of, and the
business and affairs of the Corporation managed under the direction of, its
Board of Directors, subject to any limitation set forth in the Articles of
Incorporation. Notwithstanding any provision of these Bylaws to the contrary,
the Corporation shall comply with all provisions of its Articles of
Incorporation regarding the Board of Directors, including any provisions
relating to the composition thereof or approval thereby.

     2.2 Number, Term and Election. The number of directors of the Corporation
shall be a minimum of one (1) and a maximum of five (5). The number of directors
may be fixed or changed from time to time, within the minimum and the maximum,
by the shareholders or by the Board of Directors. Only the shareholders may
change the range of the size of the Board of

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Directors or determine whether the Board of Directors shall have a fixed or
variable size. No decrease in number shall have the effect of shortening the
term of any incumbent director. Each director shall hold office until his death,
resignation, retirement or removal, or until his successor is elected.

     Except as provided in Section 2.3 of this Article, the directors (other
than initial directors) shall be elected by the holders of the Common Shares at
the annual meeting of shareholders, and those persons who receive the greatest
number of votes shall be deemed elected even though they do not receive a
majority of the votes cast. No individual shall be named or elected as a
director without his prior consent.

     2.3 Removal and Vacancies. The shareholders may remove one or more
directors, with or without cause, if the number of votes cast to remove him
constitutes a majority of the votes entitled to be cast at an election of
directors. A director may be removed by the shareholders only at a meeting
called for the purpose of removing him and the meeting notice must state that
the purpose, or one of the purposes of the meeting, is removal of the director.

     A vacancy on the Board of Directors, including a vacancy resulting from the
removal of a director or an increase in the number of directors, may be filled
by (a) the shareholders, (b) the Board of Directors or (c) the affirmative vote
of a majority of the remaining directors though less than a quorum of the Board
of Directors, and may, in the case of a resignation that will become effective
at a specified later date, be filled before the vacancy occurs but the new
director may not take office until the vacancy occurs.

     2.4 Annual and Regular Meetings. An annual meeting of the Board of
Directors, which shall be considered a regular meeting, shall be held
immediately following each annual meeting of shareholders, for the purpose of
electing officers and carrying on such other business as may properly come
before the meeting. The Board of Directors may also adopt a schedule of
additional meetings which shall be considered regular meetings. Regular meetings
shall be held at such times and at such places, within or without the
Commonwealth of Virginia, as the President or the Board of Directors shall
designate from time to time. If no place is designated, regular meetings shall
be held at the principal office of the Corporation.

     2.5 Special Meetings. Special meetings of the Board of Directors may be
called by the President or a majority of the directors of the Corporation, and
shall be held at such times and at such places, within or without the
Commonwealth of Virginia, as the person or persons calling

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the meetings shall designate. If no such place is designated in the notice of a
meeting, it shall be held at the principal office of the Corporation.

     2.6 Notice of Meetings. No notice need be given of regular meetings of the
Board of Directors.

     Notices of special meetings of the Board of Directors shall be given to
each director in person or delivered to his residence or business address (or
such other place as he may have directed in writing) not less than twenty-four
(24) hours before the meeting by mail, courier, facsimile, email, or other form
of wire or wireless communication or by telephoning such notice to him. Any such
notice shall set forth the time and place of the meeting and state the purpose
for which it is called.

     2.7 Waiver of Notice; Attendance at Meeting. A director may waive any
notice required by law, the Articles of Incorporation, or these Bylaws before or
after the date and time stated in the notice, and such waiver shall be
equivalent to the giving of such notice. Except as provided in the next
paragraph of this section, the waiver shall be in writing, signed by the
director entitled to the notice and filed with the minutes or corporate records.

     A director who attends or participates at a meeting waives any required
notice to him of the meeting unless the director, at the beginning of the
meeting or promptly upon his arrival, objects to holding the meeting or
transacting business at the meeting and does not thereafter vote for, or assent
to, action taken at the meeting.

     2.8 Quorum; Voting. A majority of the number of directors fixed in these
Bylaws shall constitute a quorum for the transaction of business at a meeting of
the Board of Directors. If a quorum is present when a vote is taken, the
affirmative vote of a majority of the directors present is the act of the Board
of Directors. A director who is present at a meeting of the Board of Directors
or a committee of the Board of Directors when corporate action is taken is
deemed to have assented to the action taken unless (a) he objects at the
beginning of the meeting, or promptly upon his arrival, to holding it or
transacting specified business at the meeting; or (b) he votes against, or
abstains from, the action taken.

     2.9 Telephonic Meetings. The Board of Directors may permit any or all
directors to participate in a regular or special meeting by, or conduct the
meeting through the use of, any means of communication by which all directors
participating may simultaneously hear each other

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during the meeting. A director participating in a meeting by this means is
deemed to be present in person at the meeting.

     2.10 Action Without Meeting. Action required or permitted to be taken at a
meeting of the Board of Directors may be taken without a meeting if the action
is taken by all members of the Board. The action shall be evidenced by one or
more written consents stating the action taken, signed by each director either
before or after the action taken, and included in the minutes or filed with the
corporate records reflecting the action taken. Action taken under this section
shall be effective when the last director signs the consent unless the consent
specifies a different effective date, in which event the action taken is
effective as of the date specified therein provided the consent states the date
of execution by each director.

     2.11 Compensation. The Board of Directors may fix the compensation of
directors and may provide for the payment of all expenses incurred by them in
attending meetings of the Board of Directors.

                                   ARTICLE III
                                    OFFICERS

     3.1  Officers. The officers of the Corporation shall be a President and a
Secretary and, in the discretion of the Board of Directors, such other officers
as may be deemed necessary or advisable to carry on the business of the
Corporation. Any two or more offices may be held by the same person.

     3.2  Election and Term. Officers shall be elected at the annual meeting of
the Board of Directors and may be elected at such other time or times as the
Board of Directors shall determine. They shall hold office, unless removed,
until the next annual meeting of the Board of Directors or until their
successors are elected. Any officer may resign at any time upon written notice
to the Board of Directors, and such resignation shall be effective when notice
is delivered unless the notice specifies a later effective date.

     3.3  Removal of Officers. The Board of Directors may remove any officer at
any time, with or without cause.

     3.4  Duties of Officers. The President shall be the chief executive officer
of the Corporation. He and the other officers shall have such powers and duties
as generally pertain to their respective offices as well as such powers and
duties as may be delegated to them from time

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to time by the Board of Directors. The President, if present, shall be chairman
of all meetings of the shareholders and the Board of Directors, as well as any
committee of which he is a member.

                                   ARTICLE IV
                               SHARE CERTIFICATES

     4.1 Form. Shares of the Corporation, when fully paid, may be evidenced by
certificates containing such information as is required by law and approved by
the Board of Directors. Any share certificates shall be signed by the President
and the Secretary and may (but need not) be sealed with the seal of the
Corporation. The seal of the Corporation and any or all signatures on a share
certificate may be facsimile. The validity of a share certificate that has been
duly signed by an officer of the Corporation shall not be affected in any way in
the event that such officer, subsequent to such signature, ceases to be an
officer of the Corporation.

     4.2 Transfer. The Board of Directors may make rules and regulations
concerning the issue, registration and transfer of certificates representing the
shares of the Corporation. Transfers of shares and of the certificates
representing such shares shall be made upon the books of the Corporation by
surrender of the certificates representing such shares accompanied by written
assignments given by the owners or their attorneys-in-fact.

     4.3 Restrictions on Transfer. A lawful restriction on the transfer or
registration of transfer of shares is valid and enforceable against the holder
or a transferee of the holder if the restriction complies with the requirements
of law and its existence is noted conspicuously on the front or back of the
certificate representing the shares. Unless so noted a restriction is not
enforceable against a person without knowledge of the restriction.

     4.4 Lost or Destroyed Share Certificates. The Corporation may issue a new
share certificate in the place of any certificate theretofore issued which is
alleged to have been lost or destroyed and may require the owner of such
certificate, or his legal representative, to give the Corporation a bond, with
or without surety, or such other agreement, undertaking or security as the Board
of Directors shall determine is appropriate, to indemnify the Corporation
against any claim that may be made against it on account of the alleged loss or
destruction or the issuance of any such new certificate.

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                                    ARTICLE V
                            MISCELLANEOUS PROVISIONS

     5.1 Corporate Seal. The corporate seal of the Corporation, if any, shall be
circular and shall have inscribed thereon, within and around the circumference
the full name of the Corporation. In the center shall be the word "SEAL" or a
substantially similar term.

     5.2 Fiscal Year. The fiscal year of the Corporation shall be determined in
the discretion of the Board of Directors, but in the absence of any such
determination it shall be the calendar year.

     5.3 Amendments. Except as otherwise provided by law, these Bylaws may be
amended or repealed, and new Bylaws may be made at any regular or special
meeting of the Board of Directors. Bylaws made by the Board of Directors may be
repealed or changed and new Bylaws may be made by the shareholders, and the
shareholders may prescribe that any Bylaw made by them shall not be altered,
amended or repealed by the Board of Directors.

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