Document:

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                              MARKEL HOLDINGS INC.

                                       TO

                    _______________________________________

                                    Trustee

                            CONTINGENT VALUE RIGHTS
                                   AGREEMENT

                                  Dated as of

                              February ____, 2000
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                               TABLE OF CONTENTS
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ARTICLE ONE......................................................................  1
 DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION.........................  1
   Section 101.  Definitions.....................................................  1
     Act.........................................................................  2
     Affiliate...................................................................  2
     Agreement...................................................................  2
     Authorized Newspaper........................................................  2
     Automatic Extinguishment....................................................  2
     Board of Directors..........................................................  2
     Board Resolution............................................................  2
     Business Day................................................................  2
     Commission..................................................................  3
     Company.....................................................................  3
     Company Request or Company Order............................................  3
     Control.....................................................................  3
     Corporate Trust Office......................................................  3
     Current Market Value........................................................  3
     CVR Certificate.............................................................  3
     Default Amount..............................................................  3
     Default Interest Rate.......................................................  3
     Default Payment Date........................................................  3
     Discounted Target Price.....................................................  3
     Disposition.................................................................  4
     Disposition Payment Date....................................................  4
     Early Redemption............................................................  4
     Early Redemption Determination Date.........................................  4
     Early Redemption Price......................................................  4
     Early Redemption Payment Date...............................................  4
     Effective Time..............................................................  4
     Events of Default...........................................................  4
     Exchange Act................................................................  4
     Holder......................................................................  4
     Independent Financial Expert................................................  4
     Maturity Date...............................................................  4
     Merger Agreement............................................................  5
     Minimum Price...............................................................  5
     Nondisposition Event........................................................  5
     Officer's Certificate.......................................................  5
     Opinion of Counsel..........................................................  5
     Outstanding.................................................................  5
     Paying Agent................................................................  6
     Person......................................................................  6
     Responsible Officer.........................................................  6

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     Security Register and Security Registrar....................................  6
     Shares......................................................................  6
     Stock.......................................................................  6
     Surviving Person............................................................  6
     Target Price................................................................  6
     Trust Indenture Act.........................................................  6
     Trustee.....................................................................  6
     Valuation Period............................................................  6
     Value Report................................................................  6
     Vice President..............................................................  6
   Section 102.  Compliance Certificates and Opinions............................  6
   Section 103.  Form of Documents Delivered to Trustee..........................  7
   Section 104.  Acts of Holders.................................................  8
   Section 105.  Notices, etc., to Trustee and Company...........................  9
   Section 106.  Notice to Holders; Waiver.......................................  9
   Section 107.  Conflict with Trust Indenture Act...............................  9
   Section 108.  Effect of Headings and Table of Contents........................  9
   Section 109.  Successors and Assigns.......................................... 10
   Section 110.  Benefits of Agreement........................................... 10
   Section 111.  Governing Law................................................... 10
   Section 112.  Legal Holidays.................................................. 10
   Section 113.  Separability Clause............................................. 10

ARTICLE TWO...................................................................... 10
 CVR FORMS....................................................................... 10
   Section 201.  Forms Generally................................................. 10
   Section 202.  Form of Face of CVR............................................. 11
   Section 203.  Form of Reverse of CVR.......................................... 12
   Section 204.  Form of Trustee's Certificate of Authentication................. 16

ARTICLE THREE.................................................................... 17
 THE CVRs........................................................................ 17
   Section 301.  Title and Terms................................................. 17
   Section 302.  Registrable Form................................................ 21
   Section 303.  Execution, Authentication, Delivery and Dating.................. 21
   Section 304.  Temporary CVRs.................................................. 22
   Section 305.  Registration, Registration of Transfer and Exchange............. 23
   Section 306.  Mutilated, Destroyed, Lost and Stolen CVRs...................... 24
   Section 307.  Presentation of CVR Certificate................................. 24
   Section 308.  Persons Deemed Owners........................................... 24
   Section 309.  Cancellation.................................................... 25

ARTICLE FOUR..................................................................... 25
 THE TRUSTEE..................................................................... 25
   Section 401.  Certain Duties and Responsibilities............................. 25
   Section 402.  Certain Rights of Trustee....................................... 26
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   Section 403.  Not Responsible for Recitals or Issuance of CVRs................ 28
   Section 404.  May Hold CVRs................................................... 28
   Section 405.  Money Held in Trust............................................. 28
   Section 406.  Compensation, Reimbursement and Indemnification of the Trustee.. 28
   Section 407.  Disqualification; Conflicting Interests......................... 29
   Section 408.  Corporate Trustee Required; Eligibility......................... 29
   Section 409.  Resignation and Removal; Appointment of Successor............... 29
   Section 410.  Acceptance of Appointment by Successor.......................... 30
   Section 411.  Merger, Conversion, Consolidation or Succession to Business..... 31

ARTICLE FIVE..................................................................... 31
 HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY............................... 31
   Section 501.  Company to Furnish Trustee Names and Addresses of Holders....... 31
   Section 502.  Preservation of Information; Communications to Holders.......... 32
   Section 503.  Reports by Trustee.............................................. 33
   Section 504.  Reports by Company.............................................. 33

ARTICLE SIX...................................................................... 34
 AMENDMENTS...................................................................... 34
   Section 601.  Amendments Without Consent of Holders........................... 34
   Section 602.  Amendments with Consent of Holders.............................. 35
   Section 603.  Execution of Amendments......................................... 35
   Section 604.  Effect of Amendments............................................ 36
   Section 605.  Conformity with Trust Indenture Act............................. 36
   Section 606.  Reference in CVRs to Amendments................................. 36

ARTICLE SEVEN.................................................................... 36
 COVENANTS....................................................................... 36
   Section 701.  Payment of Amounts, if Any, to Holders.......................... 36
     Section 702.  Maintenance of Office or Agency............................... 36
   Section 703.  Money for CVR Payments to Be Held in Trust...................... 37
   Section 704.  Certain Purchases and Sales..................................... 38
   Section 705.  Written Statement to Trustee.................................... 38

ARTICLE EIGHT.................................................................... 38
 REMEDIES OF THE TRUSTEE AND HOLDERS ON EVENT OF DEFAULT......................... 38
   Section 801.  Event of Default Defined; Acceleration of Maturity; Waiver
                 of Default...................................................... 38
   Section 802.  Collection of Indebtedness by Trustee; Trustee May Prove Debt... 40
   Section 803.  Application of Proceeds......................................... 42
   Section 804.  Suits for Enforcement........................................... 42
   Section 805.  Restoration of Rights on Abandonment of Proceedings............. 42
   Section 806.  Limitations on Suits by Holders................................. 43
   Section 807.  Unconditional Right of Holders to Institute Certain Suits....... 43
   Section 808.  Powers and Remedies Cumulative; Delay or Omission Not
                 Waiver of....................................................... 43

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   Section 809.  Control by Holders.............................................. 44
   Section 810.  Waiver of Past Defaults......................................... 44
   Section 811.  Trustee to Give Notice of Default, but May Withhold in Certain.. 45
   Section 812.  Right of Court to Require Filing of Undertaking to Pay Costs.... 45

ARTICLE NINE..................................................................... 45
 CONSOLIDATION, MERGER, SALE OR CONVEYANCE....................................... 45
   Section 901.  Company May Consolidate, Etc.................................... 45
   Section 902.  Successor Substituted........................................... 46
   Section 903.  Opinion of Counsel to Trustee................................... 46

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     AGREEMENT, dated as of February ___, 2000, between Markel Holdings Inc., a
Virginia corporation (hereinafter called the "Company"), and
____________________, trustee (hereinafter called the "Trustee").

                            RECITALS OF THE COMPANY

     WHEREAS, the Company has duly authorized the creation of an issue of
contingent value rights (hereinafter called the "CVRs"), of substantially the
tenor and amount hereinafter set forth, and to provide therefor the Company has
duly authorized the execution and delivery of this Agreement;

     WHEREAS, pursuant to the Agreement and Plan of Merger and Scheme of
Arrangement dated as of August 15, 1999, as amended December 10, 1999 and
further amended as of January 28, 2000 (the "Merger Agreement"), by and between
Markel Corporation ("Markel") and Terra Nova (Bermuda) Holdings Ltd., a Bermuda
Corporation ("Terra Nova"), the Company has agreed to issue and deliver to
stockholders of Terra Nova, among other securities, 0.07027 of a CVR for each
Class A and Class B ordinary share, par value $5.80 per share, of Terra Nova
("Terra Nova Share") issued and outstanding immediately prior to the effective
time (the "Effective Time") of the merger (except 2,069 Terra Nova Shares held
by Markel or its transferee); and

     WHEREAS, all things necessary have been done to make the CVRs, when
executed by the Company and authenticated and delivered hereunder, the valid
obligations of the Company and to make this Agreement a valid agreement of the
Company, in accordance with their and its terms.

     NOW, THEREFORE, for and in consideration of the premises and the
consummation of the transactions referred to above, it is mutually covenanted
and agreed, for the equal and proportionate benefit of all Holders of the CVRs,
as follows:

                                  ARTICLE ONE

            DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

Section 101.  Definitions.

     For all purposes of this Agreement, except as otherwise expressly provided
or unless the context otherwise requires:

          (a)  the terms defined in this Article have the meanings assigned to
     them in this Article, and include the plural as well as the singular;

          (b)  all accounting terms used herein and not expressly defined shall
     have the meanings assigned to such terms in accordance with generally
     accepted accounting principles, and the term "generally accepted accounting
     principles"

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     means such accounting principles as are generally accepted in the United
     States of America at the time of any computation;

          (c)  all other terms used herein which are defined in the Trust
     Indenture Act, either directly or by reference therein, have the meanings
     assigned to them therein; and

          (d)  the words "herein", "hereof" and "hereunder" and other words of
     similar import refer to this Agreement as a whole and not to any particular
     Article, Section or other subdivision.

     Certain terms, used principally in Article Four, are defined in that
Article.

     "Act", when used with respect to any Holder, has the meaning specified in
Section 104.

     "Affiliate" means a Person that, directly or indirectly, through one or
more intermediaries, controls, is controlled by, or is under common control
with, the first
mentioned Person.

     "Agreement" means this instrument as originally executed and as it may from
time to time be supplemented or amended pursuant to the applicable provisions
hereof.

     "Authorized Newspaper" means The Wall Street Journal (Eastern Edition), or
if The Wall Street Journal (Eastern Edition) shall cease to be published, or, if
the publication or general circulation of The Wall Street Journal (Eastern
Edition) shall be suspended for whatever reason, such other English language
newspaper as is selected by the Company with general circulation in The City of
New York, New York.

     "Automatic Extinguishment" has the meaning set forth in Section 301(l).

     "Board of Directors" means either the board of directors of the Company or
any duly authorized committee of that board.

     "Board Resolution" means a copy of a resolution certified by the Secretary
or an Assistant Secretary of the Company to have been duly adopted by the Board
of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

     "Business Day" means any day (other than a Saturday or a Sunday) on which
banking institutions in The City of New York, New York or in the State of the
principal office of the Trustee are not authorized or obligated by law or
executive order to close and, if the CVRs are listed on a national securities
exchange, such exchange is open for trading.

                                       2
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     "Commission" means the Securities and Exchange Commission, as from time to
time constituted, created under the Exchange Act, or if at any time after the
execution of this Agreement such Commission is not existing and performing the
duties now assigned to it under the Trust Indenture Act, then the body
performing such duties at such time.

     "Company" means the Person named as the "Company" in the first paragraph of
this Agreement, until a successor Person shall have become such pursuant to the
applicable provisions of this Agreement, and thereafter "Company" shall mean
such successor Person.  To the extent necessary to comply with the requirements
of the provisions of Trust Indenture Act Sections 310 through 317 as they are
applicable to the Company, the term "Company" shall include any other obligor
with respect to the CVRs for the purposes of complying with such provisions.

     "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by the chairman or vice chairman of the Board
of Directors, the president, any vice president, the controller, the treasurer,
the secretary or any assistant secretary, and delivered to the Trustee.

     "Control" (including the terms "controlled", "controlled by" and "under
common control with") means the possession, directly or indirectly or as trustee
or executor, of the power to direct or cause the direction of the management or
policies of a Person, whether through the ownership of stock or as trustee or
executor, by contract or otherwise.

     "Corporate Trust Office" means the office of the Trustee at which at any
particular time its corporate trust business shall be principally administered,
which office at the date of execution of this Agreement is located at
___________________________.

     "Current Market Value" has the meaning set forth in Section 301(g).

     "CVR Certificate" means a certificate representing any of the CVRs.

     "Default Amount" means the amount, if any, by which the Discounted Target
Price exceeds the Minimum Price.

     "Default Interest Rate" means 6% per annum.

     "Default Payment Date" means the date upon which the CVRs become due and
payable pursuant to Section 801.

     "Discounted Target Price" means, if a Disposition or an Event of Default
shall occur prior to the Maturity Date, $185.00 discounted from the Maturity
Date back to the Disposition Payment Date or the Default Payment Date, as the
case may be, at a per annum rate of 6%.  In each case, upon each occurrence of
an event specified in Section 301(k), such amounts, as they may have been
previously adjusted, shall be adjusted pursuant to Section 301(k).

                                       3
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     "Disposition" means (i) a merger, consolidation or other business
combination involving the Company as a result of which no Shares shall remain
outstanding (other than any Shares owned by the Company or any other obligor
upon the CVRs or any Affiliate of the Company or any such other obligor), (ii) a
sale, transfer or other disposition, in one or a series of transactions, of all
or substantially all of the assets of the Company or (iii) a reclassification of
Shares as any other capital stock of the Company or any other Person; unless in
the case of clauses (i) and (ii) such transaction is in connection with a
transaction in which all of the Shares are exchanged solely for other publicly
traded equity securities of the Company or another Person, the successor assumes
the obligations of the Company relating to the CVRs, and appropriate adjustments
are made to the Target Price, the Minimum Price, the Discounted Target Price and
other terms hereof to reflect such transaction and the economic benefits
intended to be conferred on the CVRs under this Agreement (a "Nondisposition
Event").

     "Disposition Payment Date" has the meaning set forth in Section 301(e).

     "Early Redemption" has the meaning set forth in Section 203.

     "Early Redemption Determination Date" means the date five Business Days
prior to the date, if any, upon which the Company issues a notice of redemption
of the CVRs prior to the Maturity Date pursuant to Section 301(d).

     "Early Redemption Payment Date" means the date upon which the Early
Redemption Price is paid to the Trustee in connection with an Early Redemption,
which shall also be the redemption date.

     "Early Redemption Price" means a price equal to the difference between the
Target Price and the Current Market Price as at five Business Days prior to the
date that a notice of redemption is issued pursuant to Section 301(d),
discounted from the Maturity Date to the Early Redemption Payment Date at a per
annum rate of 6%.

     "Effective Time" has the meaning set forth in the Preamble.

     "Event of Default" has the meaning set forth in Section 801.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended.

     "Holder" means a Person in whose name a CVR is registered in the Security
Register.

     "Independent Financial Expert" means an independent nationally recognized
investment-banking firm.

     "Maturity Date" means the date that is the first day after the expiration
of thirty (30) months from the Effective Time.

                                       4
<PAGE>

     "Merger Agreement" has the meaning as set forth in the recitals.

     "Minimum Price" means $140.00.  In each case, upon each occurrence of an
event specified in Section 301(k), such amount, as it may have been previously
adjusted, shall be adjusted pursuant to Section 301(k).

     "Nondisposition Event" has the meaning as set forth in the definition of
"Disposition".

     "Officer's Certificate'" means a certificate signed by the chairman or vice
chairman of the Board of Directors, the president, any vice president, the
controller, the treasurer, the secretary or any assistant secretary of the
Company in his or her capacity as such an officer, and delivered to the Trustee.

     "Opinion of Counsel" means a written opinion of counsel, who may be General
Counsel for the Company, and who shall be reasonably acceptable to the Trustee.

     "Outstanding", when used with respect to CVRs, means, as of the date of
determination, all CVRs theretofore authenticated and delivered under this
Agreement, except:

          (a)  CVRs theretofore cancelled by the Trustee or delivered to the
     Trustee for cancellation;

          (b)  From and after the earlier of the Default Payment Date, the
     Disposition Payment Date, Early Redemption Payment Date or the Maturity
     Date, CVRs, or portions thereof, for whose payment in cash or securities of
     the Company in the necessary amount has been theretofore deposited with the
     Trustee or any Paying Agent (other than the Company) in trust or set aside
     and segregated in trust by the Company (if the Company shall act as its own
     Paying Agent) for the Holders of such CVRs; and

          (c)  CVRs in exchange for or in lieu of which other CVRs have been
     authenticated and delivered pursuant to this Agreement, other than any such
     CVRs in respect of which there shall have been presented to the Trustee
     proof satisfactory to it that such CVRs are held by a bona fide purchaser
     in whose hands the CVRs are valid obligations of the Company;

provided, however, that in determining whether the Holders of the requisite
Outstanding CVRs have given any request, demand, direction, consent or waiver
hereunder, CVRs owned by the Company or any other obligor upon the CVRs or any
Affiliate of the Company or such other obligor shall be disregarded and deemed
not to be Outstanding, except that, in determining whether the Trustee shall be
protected in relying upon any such request, demand, direction, consent or
waiver, only CVRs which the Trustee knows to be so owned shall be so
disregarded.

                                       5
<PAGE>

     "Paying Agent" means any Person authorized by the Company to pay the amount
determined pursuant to Section 301, if any, on any CVRs on behalf of the
Company, which shall initially be __________________________.

     "Person" has the meaning set forth in Section 901.

     "Responsible Officer", when used with respect to the Trustee, means any
officer assigned to the Corporate Trust Office and also means, with respect to
any particular corporate trust matter, any other officer of the Trustee to whom
such matter is referred because of his knowledge of and familiarity with the
particular subject.

     "Security Register" and "Security Registrar" have the respective meanings
specified in Section 305.

     "Shares" means the common shares, no par value, of the Company.

     "Stock" has the meaning as set forth in Section 202.

     "Surviving Person" means any individual, corporation, partnership, joint
venture, limited liability company, association, joint-stock company, trust,
unincorporated organization or government or any agency or political subdivision
thereof.

     "Target Price" means $185.00.  In each case, upon each occurrence of an
event specified in Section 301(k), such amount, as it may have been previously
adjusted, shall be adjusted pursuant to Section 301(k).

     "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at
the date as of which this Agreement was executed, except as provided in Section
605.

     "Trustee" means the Person named as the "Trustee" in the first paragraph of
this Agreement, until a successor Trustee shall have become such pursuant to the
applicable provisions of this Agreement, and thereafter "Trustee" shall mean
such successor Trustee.

     "Valuation Period" has the meaning set forth in Section 301(g).

     "Value Report" has the meaning set forth in Section 301(h).

     "Vice President", when used with respect to the Company or the Trustee,
means any vice president, whether or not designated by a number or a word or
words added before or after the title of "vice president".

Section 102.  Compliance Certificates and Opinions.

     Upon any application or request by the Company to the Trustee to take any
action under any provision of this Agreement, the Company shall furnish to the
Trustee an

                                       6
<PAGE>

Officer's Certificate stating that all conditions precedent, if any, provided
for in this Agreement (including any covenants, compliance with which
constitutes a condition precedent) relating to the proposed action have been
complied with and an Opinion of Counsel stating that in the opinion of such
counsel all such conditions precedent, if any, have been complied with, except
that, in the case of any such application or request as to which the furnishing
of such documents is specifically required by any provision of this Agreement
relating to such particular application or request, no additional certificate or
opinion need be furnished.

     Every certificate or opinion with respect to compliance with a condition or
covenant provided for in this Agreement shall include:

          (a)  a statement that each individual signing such certificate or
     opinion has read such covenant or condition and the definitions herein
     relating thereto;

          (b)  a brief statement as to the nature and scope of the examination
     or investigation upon which the statements or opinions contained in such
     certificate or opinion are based;

          (c)  a statement that, in the opinion of each such individual, he has
     made such examination or investigation as is necessary to enable him to
     express an informed opinion as to whether or not such covenant or condition
     has been complied with; and

          (d)  a statement as to whether, in the opinion of each such
     individual, such condition or covenant has been complied with.

Section 103.  Form of Documents Delivered to Trustee.

     In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

     Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to the matters upon which his certificate or opinion is based are
erroneous.  Any such certificate or Opinion of Counsel may be based, insofar as
it relates to factual matters, upon a certificate or opinion of, or
representations by, an officer or officers of the Company stating that the
information with respect to such factual matters is in the possession of the
Company, unless such counsel knows, or in the exercise of reasonable care should
know, that the certificate or opinion or representations with respect to such
matters are erroneous.

                                       7
<PAGE>

     Any certificate, statement or opinion of an officer of the Company or of
counsel may be based, insofar as it relates to accounting matters, upon a
certificate or opinion of or representations by an accountant or firm of
accountants in the employ of the Company, unless such officer or counsel, as the
case may be, knows that the certificate or opinion or representations with
respect to the accounting matters upon which his certificate, statement or
opinion may be based as aforesaid are erroneous, or in the exercise of
reasonable care should know that the same are erroneous.  Any certificate or
opinion of any independent firm of public accountants filed with the Trustee
shall contain a statement that such firm is independent.

     Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Agreement, they may, but need not, be consolidated and
form one instrument.

Section 104.  Acts of Holders.

     (a)  Any request, demand, authorization, direction, notice, consent, waiver
or other action provided by this Agreement to be given or taken by Holders may
be embodied in and evidenced by one or more instruments of substantially similar
tenor signed by such Holders in person or by an agent duly appointed in writing;
and, except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments are delivered to the Trustee and,
where it is hereby expressly required, to the Company.  Such instrument or
instruments (and the action embodied therein and evidenced thereby) are herein
sometimes referred to as the "Act" of the Holders signing such instrument or
instruments.  Proof of execution of any such instrument or of a writing
appointing any such agent shall be sufficient for any purpose of this Agreement
and (subject to Section 401) conclusive in favor of the Trustee and the Company,
if made in the manner provided in this Section.

     (b)  The fact and date of the execution by any Person of any such
instrument or writing may be proved in any reasonable manner that the Trustee
deems sufficient.

     (c)  The ownership of CVRs shall be proved by the Security Register.

     (d)  At any time prior to (but not after) the evidencing to the Trustee, as
provided in this Section 104, of the taking of any action by the Holders of the
CVRs specified in this Agreement in connection with such action, any Holder of a
CVR may, by filing written notice at the Corporate Trust Office and upon proof
of holding as provided in this Section 104, revoke such action so far as it
concerns such CVR.  Any request, demand, authorization, direction, notice,
consent, waiver or other action by the Holder of any CVR shall bind every future
Holder of the same CVR or the Holder of every CVR issued upon the registration
of transfer thereof or in exchange therefor or in lieu thereof, in respect of
anything done, suffered or omitted to be done by the Trustee, any Paying Agent
or the Company in reliance thereon, whether or not notation of such action is
made upon such CVR.

                                       8
<PAGE>

Section 105.  Notices, etc., to Trustee and Company.

     Any request, demand, authorization, direction, notice, consent, waiver or
Act of Holders or other document provided or permitted by this Agreement to be
made upon, given or furnished to, or filed with:

          (a)  the Trustee by any Holder or by the Company shall be sufficient
     for every purpose hereunder if made, given, furnished or filed, in writing,
     to or with the Trustee at ______________________________________________.

          (b)  the Company by the Trustee or by any Holder shall be sufficient
     for every purpose hereunder if in writing and mailed, first-class postage
     prepaid, to the Company addressed to it at 4521 Highwoods Parkway, Glen
     Allen, Virginia 23060, Attention:  Steven A. Markel and Gregory B. Nevers,
     or at any other address previously furnished in writing to the Trustee by
     the Company.

Section 106.  Notice to Holders; Waiver.

     Where this Agreement provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first-class postage prepaid, to each Holder affected
by such event, at his address as it appears in the Security Register, not later
than the latest date, and not earlier than the earliest date, prescribed for the
giving of such notice.  In any case where notice to Holders is given by mail,
neither the failure to mail such notice, nor any defect in any notice so mailed,
to any particular Holder shall affect the sufficiency of such notice with
respect to other Holders. Where this Agreement provides for notice in any
manner, such notice may be waived in writing by the Person entitled to receive
such notice, either before or after the event, and such waiver shall be the
equivalent of such notice.  Waivers of notice by Holders shall be filed with the
Trustee, but such filing shall not be a condition precedent to the validity of
any action taken in reliance upon such waiver.

     In case by reason of the suspension of regular mail service or by reason of
any other cause, it shall be impracticable to mail notice of any event as
required by any provision of this Agreement, then any method of giving such
notice as shall be satisfactory to the Trustee shall be deemed to be a
sufficient giving of such notice.

Section 107.  Conflict with Trust Indenture Act.

     If any provision hereof limits, qualifies or conflicts with another
provision hereof which is required to be included in this Agreement by any of
the provisions of the Trust Indenture Act, such required provision shall
control.

Section 108.  Effect of Headings and Table of Contents.

                                       9
<PAGE>

     The Article and Section headings herein and the Table of Contents are for
convenience only and shall not affect the construction hereof.

Section 109.  Successors and Assigns.

     All covenants and agreements in this Agreement by the Company shall bind
its successors and assigns, whether so expressed or not.

Section 110.  Benefits of Agreement.

     Nothing in this Agreement or in the CVRs, express or implied, shall give to
any Person (other than the parties hereto and their successors hereunder, any
Paying Agent and the Holders) any benefit or any legal or equitable right,
remedy or claim under this Agreement or under any covenant or provision herein
contained, all such covenants and provisions being for the sole benefit of the
parties hereto and their successors and of the Holders.

Section 111.  Governing Law.

     This Agreement and the CVRs shall be governed by and construed in
accordance with the laws of the Commonwealth of Virginia.

Section 112.  Legal Holidays.

     In the event that the Maturity Date, the Disposition Payment Date, the
Early Redemption Payment Date or the Default Payment Date, as the case may be,
shall not be a Business Day, then (notwithstanding any provision of this
Agreement or the CVRs to the contrary) payment on the CVRs need not be made on
such date, but may be made on the next succeeding Business Day with the same
force and effect as if made on the Maturity Date, the Disposition Payment Date,
the Early Redemption Payment Date or the Default Payment Date, as the case may
be.

Section 113.  Separability Clause.

     In case any provision in this Agreement or in the CVRs shall be invalid,
illegal or unenforceable, the validity, legality and enforceability of the
remaining provisions shall not in any way be affected or impaired thereby.

                                  ARTICLE TWO

                                   CVR FORMS

Section 201.  Forms Generally.

                                       10
<PAGE>

     The CVRs and the Trustee's certificate of authentication shall be in
substantially the forms set forth in this Article, with such appropriate
insertions, omissions, substitutions and other variations as are required or
permitted by this Agreement and may have such letters, numbers or other marks of
identification and such legends or endorsements placed thereon as may be
required to comply with the rules of any securities exchange or as may be
required by law or any rule or regulation pursuant thereto, all as may be
determined by officers executing such CVRs, as evidenced by their execution of
the CVRs.  Any portion of the text of any CVR may be set forth on the reverse
thereof, with an appropriate reference thereto on the face of the CVR.

     The definitive CVRs shall be printed, lithographed or engraved or produced
by any combination of these methods or may be produced in any other manner as
determined by the officers executing such CVRs, as evidenced by their execution
of such CVRs.

Section 202.  Form of Face of CVR.

                              MARKEL HOLDINGS INC.

No. CVRs __________           Certificate for Contingent Value Rights

     This certifies that __________________ or registered assigns (the "Holder")
is the registered holder of the number of Contingent Value Rights ("CVRs") set
forth above.  Each CVR entitles the Holder, subject to the provisions contained
herein and in the Agreement referred to on the reverse hereof, to a payment from
Markel Holdings Inc., a Virginia corporation (the "Company"), in an amount and
in the form determined pursuant to the provisions set forth on the reverse
hereof and as more fully described in the Agreement.  Such payment shall be
made, if in Cash (as defined below) on the third Business Day following, or if
in Stock (as defined below) as promptly as practicable after, the Maturity Date,
or on the Default Payment Date or the Early Redemption Payment Date or the
Disposition Payment Date upon the occurrence of an Event of Default or a
Disposition, as the case may be, each as defined in the Agreement referred to on
the reverse hereof.

     Payment of any amounts pursuant to this CVR Certificate shall be made only
upon presentation of this CVR Certificate by the Holder hereof, at the office or
agency of the Company maintained for that purpose.  Such payment, including
payments after a Disposition, Event of Default or Early Redemption, shall be
made in the Borough of Manhattan, The City of New York, or at any other office
or agency maintained by the Company for such purpose either, in the Company's
sole discretion, (i) in such coin or currency of the United States of America as
at the time is legal tender for the payment of public and private debts;
provided, however, the Company may pay such amounts by its check payable in such
money ("Cash") or (ii) by delivering the equivalent fair market value of Shares,
valued at the mean of the averages of the high and low and opening and closing
prices on the New York Stock Exchange (or, if the Shares are not listed thereon,
the principal other exchange upon which such shares are then listed) of Shares
during the

                                       11
<PAGE>

20 consecutive trading day period ending on the date preceding the date the
amounts are due ("Stock"). ___________________ has been appointed as Paying
Agent in the Borough of Manhattan, The City of New York.

     Reference is hereby made to the further provisions of this CVR Certificate
set forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been duly executed by
the Trustee referred to on the reverse hereof by manual signature, this CVR
Certificate shall not be entitled to any benefit under the Agreement or be valid
or obligatory for any purpose.

     IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated:  February ____, 2000      MARKEL HOLDINGS INC.

                                 By
                                   _________________________________

Attest:
SEAL

_______________________________
Authorized Signature

Section 203.  Form of Reverse of CVR.

     This CVR Certificate is issued under and in accordance with the Contingent
Value Rights Agreement, dated as of  February ____, 2000 (the "Agreement"),
between the Company and ________________, trustee (the "Trustee", which term
includes any successor Trustee under the Agreement), and is subject to the terms
and provisions contained in the Agreement, all of which terms and provisions the
Holder of this CVR Certificate consents by acceptance hereof. The Agreement is
hereby incorporated herein by reference and made a part hereof.  Reference is
hereby made to the Agreement for a full statement of the respective rights,
limitations of rights, duties, obligations and immunities thereunder of the
Company, the Trustee and the Holders of the CVRs.  Copies of the Agreement can
be obtained by contacting the Trustee.

     Subject to adjustment pursuant to Section 301(k) of the Agreement, and
subject to Section 301(l) of the Agreement, the Company shall pay to the Holder
hereof, if in Cash,

                                       12
<PAGE>

on the third Business Day following, or if in Stock as promptly as practicable
after, ______________ (the "Maturity Date"), an amount, if any, as determined
by the Company, by which the Target Price exceeds the greater of (i) the Current
Market Value and (ii) the Minimum Price. Such determination by the Company
absent manifest error shall be final and binding on the Company and the Holder.

     Such amount, if any, shall be payable by the Company, either, in the
Company's sole discretion, (i) Cash or (ii) Stock.  ______________ has been
appointed as Paying Agent in the Borough of Manhattan, The City of New York. All
payments to be made by the Company pursuant to this CVR Certificate shall be
subject to and reduced by withholding taxes, if any. The Company shall have no
obligation to reimburse, equalize, or compensate a Holder or other person for
such withholding taxes.

     The Company may redeem all, but not less than all, of the CVRs at any
time upon not less than 30 days notice at a price per CVR (the "Early Redemption
Price") equal to the difference between the Target Price and the Current Market
Value as at the Early Redemption Determination Date, discounted from the
Maturity Date to the Early Redemption Payment Date at a per annum rate of 6% (an
"Early Redemption").  The Early Redemption Price shall be payable by the Company
in the Company's sole discretion either in (i) Cash or (ii) Stock.  Nothing in
the Agreement shall limit the Company's ability to purchase or otherwise acquire
CVRs through open market transactions, privately negotiated transactions, or
otherwise.

     Upon the consummation of a Disposition, the Company shall pay to the Holder
hereof (in Cash or Stock, at the Company's sole discretion) for each CVR
represented hereby an amount, if any, as determined by the Company, by which the
Discounted Target Price exceeds the greater of (i) the fair market value, as
determined by an Independent Financial Expert, of the consideration, if any,
received for each Share by the holder thereof as a result of such Disposition,
assuming that such holder did not exercise any right of appraisal granted under
law with respect to such Disposition, and (ii) the Minimum Price.  Such
determinations by the Company and such Independent Financial Expert absent
manifest error shall be final and binding on the Company and the Holder.  Such
payment shall be made on the date (the "Disposition Payment Date") established
by the Company, which in no event shall be more than 30 days after the date on
which the Disposition was consummated.  As soon as practicable after the
Disposition, the Company shall give the Holder hereof and the Trustee notice of
such Disposition and the Disposition Payment Date, as provided in Section 301(e)
of the Agreement.

     If an Event of Default occurs and is continuing, either the Trustee or the
Holders holding an aggregate of at least 25% of the Outstanding CVRs, by notice
to the Company (and to the Trustee if given by the Holders), may declare the
CVRs due and payable, and upon such declaration, the Company shall pay to the
Holder (in Cash or Stock, at the Company's sole discretion) for each CVR held by
the Holder the Default Amount with interest at a rate of 6% per annum from the
Default Payment Date through the date payment is made or duly provided for.

     In the event that the Company determines that no amount is payable on the
CVRs to the Holder on the Maturity Date or the Disposition Payment Date, as the
case may be, as a result of Automatic Extinguishment or otherwise, the Company
shall give to the

                                       13
<PAGE>

Holder and the Trustee notice of such determination. Upon making such
determination, absent manifest error, this CVR Certificate shall terminate and
become null and void and the Holder hereof shall have no further rights with
respect hereto. The failure to give such notice or any defect therein shall not
affect the validity of such determination.

     If the Current Market Value of the Company's Shares during any 20
consecutive trading days in the Valuation Period is greater than or equal to
$185.00 per Share, the CVRs will automatically be extinguished without further
consideration or action by the Company or the Holders ("Automatic
Extinguishment").

     Notwithstanding any provision of the Agreement or of this CVR Certificate
to the contrary, other than in the case of interest on the Default Amount, no
interest shall accrue on any amounts payable on the CVRs to the Holder.

     "Authorized Newspaper" means The Wall Street Journal (Eastern Edition), or
if The Wall Street Journal (Eastern Edition) shall cease to be published, or, if
the publication or general circulation of The Wall Street Journal (Eastern
Edition) shall be suspended for whatever reason, such other English language
newspaper as is selected by the Company with general circulation in The City of
New York, New York.

     "Current Market Value" shall be, during the 20 consecutive trading day
period that both begins and ends in the Valuation Period and which yields the
highest such averages for any such 20 consecutive trading day period within the
Valuation Period: (i) the mean of the averages of the high and low and opening
and closing prices, regular way, on the New York Stock Exchange (or, if the
Shares are not listed thereon, the principal other exchange on which such shares
are then listed); (ii) if the Shares are not then listed or admitted to trading
on any securities exchange, mean of the averages of the high and low and opening
and closing sale price on such days, or if no sale takes place on such days, the
mean of the averages of the high and low and opening and closing bid and asked
prices on such days, as reported by a reputable quotation source designated by
the Company; or (iii) if the Shares are not then listed or admitted to trade on
any securities exchange and no such reported sale price or bid and asked prices
are available, the mean of the averages of the reported high and low and opening
and closing bid and asked prices on those days on which such information is
available, as reported in the Authorized Newspaper.  Notwithstanding the
foregoing, in computing Current Market Value for purposes of an Early Redemption
or the Automatic Extinguishment, no such 20 consecutive day period may be
included in which the Company, any of its subsidiaries or controlled Affiliates
or Steven A. Markel, Anthony F. Markel or Alan I. Kirshner purchase any Shares
except (x) in privately negotiated transactions that are not reported to any
exchange (other than as a result of being disclosed in a filing with the
Commission that is also required to be filed with such exchange), (y) with
respect to employee benefit plans and other incentive compensation arrangements
in the ordinary course of business and (z) purchases in compliance with Rule
10b-18 promulgated under the Exchange Act.

                                       14
<PAGE>

     "Default Amount" means the amount, if any, by which the Discounted Target
Price exceeds the Minimum Price.

     "Default Payment Date" means the date upon which the CVRs become due and
payable pursuant to Section 801 of the Agreement.

     "Discounted Target Price" means, if a Disposition or an Event of Default
shall occur prior to the Maturity Date, $185.00 discounted from the Maturity
Date back to the Disposition Payment Date or the Default Payment Date, as the
case may be, at a per annum rate of 6%.  In each case, upon each occurrence of
an event specified in Section 301(k) of the Agreement, such amount, as it may
have been previously adjusted, shall be adjusted pursuant to Section 301(k) of
the Agreement.

     "Disposition" means (i) a merger, consolidation or other business
combination involving the Company as a result of which no Shares shall remain
outstanding (other than any Shares owned by the Company or any other obligor
upon the CVRs or any Affiliate of the Company or any such other obligor), (ii) a
sale, transfer or other disposition, in one or a series of transactions, of all
or substantially all of the assets of the Company or (iii) a reclassification of
Shares as any other capital stock of the Company or any other Person; unless in
the case of clauses (i) and (ii) such transaction is in connection with a
transaction in which all of the Shares are exchanged solely for other publicly
traded equity securities of the Company or another Person, the successor assumes
the obligations of the Company relating to the CVRs, and appropriate adjustments
are made to the Target Price, the Minimum Price, the Discounted Target Price and
other terms hereof to reflect such transaction and the economic benefits
intended to be conferred on the CVRs under this Agreement (a "Nondisposition
Event").

     "Early Redemption Determination Date" means the date five business
days prior to the date, if any, upon which the Company issues a notice of
redemption of the CVRs prior to the Maturity Date.

     "Event of Default" has the meaning set forth in Section 801 of the
Agreement.

     "Independent Financial Expert" means an independent nationally recognized
investment-banking firm.

     The "Minimum Price" means $140.00.  In each case, upon each occurrence of
an event specified in Section 301(k) of the Agreement, such amount, as it may
have been previously adjusted, shall be adjusted pursuant to Section 301(k) of
the Agreement.

     "Shares" means the common shares, no par value, of the Company.

     The "Target Price" means $185.00.  In each case, upon each occurrence of an
event specified in Section 301(k) of the Agreement, such amount, as it may have
been previously adjusted, shall be adjusted pursuant to Section 301(k) of the
Agreement.

                                       15
<PAGE>

     "Valuation Period" has the meaning specified in Section 301(g) of the
Agreement.

     The Agreement permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of CVRs under the Agreement at any time by
the Company and the Trustee with the consent of the Holders of a majority of the
CVRs at the time outstanding.

     No reference herein to the Agreement and no provision of this CVR
Certificate or of the Agreement shall alter or impair the obligation of the
Company, which is absolute and unconditional, to pay any amounts determined
pursuant to the terms hereof and of the Agreement at the times, place, and
amount, and in the Cash or Stock, herein prescribed.

     As provided in the Agreement and subject to certain limitations therein set
forth, the transfer of the CVRs represented by this CVR Certificate is
registerable on the Security Register of the Company, upon surrender of this CVR
Certificate for registration of transfer at the office or agency of the Company
maintained for such purpose in the City of New York or Richmond, Virginia, duly
endorsed by, or accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed by, the
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new CVR Certificates, for the same amount of CVRs, will be issued to the
designated transferee or transferees.  The Company hereby initially designates
the office of ___________ as the office for registration of transfer of this CVR
Certificate.

     As provided in the Agreement and subject to certain limitations therein set
forth, this CVR Certificate is exchangeable for one or more CVR Certificates
representing the same number of CVRs as represented by this CVR Certificate as
requested by the Holder surrendering the same.

     No service charge will be made for any registration of transfer or exchange
of CVRs, but the Company may require payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

     Prior to the time of due presentment of this CVR Certificate for
registration of transfer, the Company, the Trustee and any agent of the Company
or the Trustee may treat the Person in whose name this CVR Certificate is
registered as the owner hereof for all purposes, and neither the Company, the
Trustee nor any agent shall be affected by notice to the contrary.

     All capitalized terms used in this CVR Certificate without definition shall
have the meanings assigned to them in the Agreement.

Section 204.  Form of Trustee's Certificate of Authentication'.

                    TRUSTEE'S CERTIFICATE OF AUTHENTICATION.

                                       16
<PAGE>

     This is one of the CVR Certificates referred to in the within-mentioned
Agreement.

                        _______________________________

                                    Trustee

                            By_____________________
                               Authorized Officer

                                 ARTICLE THREE

                                    THE CVRs

Section 301.  Title and Terms.

     (a)  The aggregate number of CVR Certificates which may be authenticated
and delivered under this Agreement is limited to __________, except for CVRs
authenticated and delivered upon registration of transfer of, or in exchange
for, or in lieu of, other CVRs pursuant to Section 304, 305, 306 or 606 of this
Agreement. The Company will not issue any fractional CVRs, and in lieu thereof,
will make a pro rata cash payment in an amount equivalent to the fair market
value of any fraction of a CVR due under the Merger Agreement.

     (b)  The CVRs shall be known and designated as the "Contingent Value
Rights" of the Company and shall be unsecured obligations of the Company that
rank equally with all other unsecured obligations of the Company and the Holders
shall have no rights except for those rights explicitly provided for herein and
shall not, by virtue of their ownership of CVRs have any of the rights of a
shareholder of the Company.

     (c)  Subject to adjustment pursuant to Section 301(k) and subject to
Section 301(l), the Company shall pay to each Holder, if in Cash, on the third
Business Day following the Maturity Date, or if in Stock, as promptly as
practicable after the Maturity Date, for each CVR held by such Holder, an
amount, if any, as determined by the Company, by which the Target Price exceeds
the greater of (i) the Current Market Value and (ii) the Minimum Price.  Such
determinations by the Company absent manifest error shall be final and binding
on the Company and the Holders.  Not later than the second Business Day after
the Maturity Date, the Company shall (x) prepare and file with the Trustee a
certificate setting forth such determinations (including, if the amount payable
is to be paid in Stock, the Company's calculation of the amount of Stock to be
paid) and the facts accounting for such determinations and (y) mail to each
Holder a brief summary of

                                       17
<PAGE>

such certificate, stating whether the amount payable will be paid in Cash or
Stock, and indicating the locations at which CVRs may be presented for payment.

     (d) The Company may redeem all, but not less than all, of the CVRs at any
time upon not less than 30 Business Days notice at a price per CVR (the "Early
Redemption Price") equal to the difference between the Target Price and the
Current Market Value as at the Early Redemption Determination Date, discounted
from the Maturity Date to the Early Redemption Payment Date at a per annum rate
of 6% (an "Early Redemption").  The Early Redemption Price shall be payable by
the Company in the Company's sole discretion either in (i) Cash or (ii) Stock.
Such option shall be exercised by (i) publishing notice of such redemption in
the Authorized Newspaper and (ii) furnishing notice, in the form set forth
below, to the Trustee and each Holder of such redemption, in each case, not less
than thirty (30) Business Days before the redemption date, provided, that no
defect in any such notice shall affect the validity of the redemption, and that
any notice when published and mailed to the Trustee and a Holder in the
aforesaid manner shall be conclusively deemed to have been received by such
Holder whether or not actually received by such Holder. Nothing in this
Agreement shall limit the Company's ability to purchase or otherwise acquire
CVRs through open market transactions, privately negotiated transactions, or
otherwise.

                                 * * * * * * *

                                       18
<PAGE>

                              MARKEL HOLDINGS INC.

                            CONTINGENT VALUE RIGHTS

                                     [DATE]

                              NOTICE OF REDEMPTION

     NOTICE IS HEREBY GIVEN THAT, pursuant to Section 301 of the Contingent
Value Rights Agreement, dated as of February ___, 2000 (the "Agreement"),
between Markel Holdings Inc. (the "Company") and _________________, as trustee
(the "Trustee"), the Company has redeemed the Contingent Value Rights.  All
terms used in this Notice that are defined in the Agreement shall have the
meanings assigned to them in the Agreement.  Each and every currently
outstanding CVR will be redeemed at a price equal to the difference between the
[TARGET PRICE] and the current market value of a Share as of [DATE], discounted
from [MATURITY DATE] to [EARLY REDEMPTION PAYMENT DATE] at a per annum rate of
6%, less applicable withholding taxes, if any.

                                 * * * * * * *
Promptly after the Early Redemption Payment Date, the Company shall (x) prepare
and file with the Trustee a certificate setting forth the Company's
determination of the Early Redemption Price (including, if the amount payable is
to be paid in Stock, the Company's calculation of the amount of Stock to be
paid) and the facts accounting for such determination and (y) mail to each
Holder a brief summary of such certificate, indicating the locations at which
CVRs may be presented for payment.

     (e)  Upon the consummation of a Disposition, the Company shall pay (in the
manner provided in Section 307) to each Holder for each CVR held by such Holder
an amount, if any, as determined by the Company, by which the Discounted Target
Price exceeds the greater of (i) the cash amount received for each Share by the
holder thereof as a result of such disposition, plus the fair market value, as
determined by an Independent Financial Expert, of the non-cash consideration, if
any, received for each Share by the holder thereof as a result of such
Disposition, assuming that such Holder did not exercise any right of appraisal
granted under law with respect to such Disposition, and (ii) the Minimum Price.
Such determinations by the Company and such Independent Financial Expert absent
manifest error shall be final and binding on the Company and the Holders.  Such
payment shall be made on the date (the "Disposition Payment Date") established
by the Company, which in no event shall be more than 30 days after the date on
which the Disposition was consummated.

     (f)  As soon as practicable, the Company shall (x) prepare and file with
the Trustee a certificate setting forth the determinations referred to in
Section 301(e) (including, if the amount payable is to be paid in Stock, the
Company's calculation of the amount of Stock to be paid) and the facts
accounting for such determinations and (y) mail to each Holder a brief summary
of such certificate, indicating the locations at which

                                       19
<PAGE>

CVRs may be presented for payment and the date on which the payment referred to
in Section 301(e) shall be made.

     (g) The current market value per Share (the "Current Market Value") shall
be, during the 20 consecutive trading day period that both begins and ends in
the Valuation Period and which yields the highest such averages for any such 20
consecutive trading day period within the Valuation Period: (i) the mean of the
averages of the high and low and opening and closing prices, regular way, on the
New York Stock Exchange (or, if the Shares are not listed thereon, the principal
other exchange on which such shares are then listed); (ii) if the Shares are not
then listed or admitted to trading on any securities exchange, the mean of the
averages of the high and low and opening and closing sale price on such days, or
if no sale takes place on such days, the mean of the averages of the high and
low and opening and closing bid and asked prices on such days, as reported by a
reputable quotation source designated by the Company; or (iii) if the Shares are
not then listed or admitted to trade on any securities exchange and no such
reported sale price or bid and asked prices are available, the mean of the
averages of the reported high and low and opening and closing bid and asked
prices on those days on which such information is available, as reported in the
Authorized Newspaper. Notwithstanding the foregoing, in computing Current Market
Value for purposes of an Early Redemption or the Automatic Extinguishment, no
such 20 consecutive day period may be included in which the Company, any of its
subsidiaries or controlled Affiliates or Steven A. Markel, Anthony F. Markel or
Alan I. Kirshner purchase any Shares except (x) in privately negotiated
transactions that are not reported on any exchange (other than as a result of
being disclosed in a filing with the Commission that is also required to be
filed with such exchange), (y) with respect to employee benefit plans and other
incentive compensation arrangements in the ordinary course of business and
(z) purchases in compliance with Rule 10b-18 promulgated under the Exchange Act.

     "Valuation Period" means (i) with respect to a payment at the Maturity
Date, the 60 day trading period immediately preceding (and including) the
Maturity Date, and (ii) with respect to an Automatic Extinguishment or an Early
Redemption, the period of time after the Effective Time and ending on the
Maturity Date.

     (h)  In the event the Current Market Value or fair market value, as the
case may be, is determined by an Independent Financial Expert, the Company shall
cause the Independent Financial Expert to deliver to the Company, with a copy to
the Trustee, a value report (the "Value Report") stating the methods of
valuation considered or used and, if applicable, the per share value of the
Shares, and containing a statement as to the nature and scope of the examination
or investigation upon which the determination of value was made. The Trustee
shall make available a copy of the Value Report to each Holder who requests such
Value Report. The determination of the Independent Financial Expert as set forth
in the Value Report absent manifest error shall be final and binding on the
Company and the Holders.

     (i)  Notwithstanding any provision of this Agreement or the CVR
Certificates to the contrary, other than in the case of interest on the Default
Amount, no interest shall accrue on any amounts payable on the CVRs to any
Holder.

                                       20
<PAGE>

     (j)  In the event that the Company determines that no amount is payable on
the CVRs to the Holders on the Maturity Date, or the Disposition Payment Date,
as the case may be, as a result of an Automatic Extinguishment or otherwise, the
Company shall give to the Trustee and each Holder notice of such determination.
Upon making such determination, absent manifest error, the CVR Certificates
shall terminate and become null and void and the Holders thereof shall have no
further rights with respect thereto. The failure to give such notice or any
defect therein shall not affect the validity of such determination.

     (k)  In the event the Company shall in any manner subdivide (by stock
split, stock dividend or otherwise) or combine (by reverse stock split or
otherwise) the number of outstanding Shares, the Company shall similarly
subdivide or combine the CVRs and shall appropriately adjust the Discounted
Target Price, the Target Price, the Early Redemption Price and the Minimum
Price.  In the case of a Nondisposition Event, appropriate adjustments will be
made to the Target Price, the Minimum Price, the Discounted Target Price, and
the Early Redemption Price.  Whenever an adjustment is made as provided in this
Section 301(k), the Company shall (i) promptly prepare a certificate setting
forth such adjustment and a brief statement of the facts accounting for such
adjustment, (ii) promptly file with the Trustee a copy of such certificate and
(iii) mail a brief summary thereof to each Holder.  The Trustee shall be fully
protected in relying on any such certificate and on any adjustment therein
contained.  Such adjustment absent manifest error shall be final and binding on
the Company and the Holders.  Each outstanding CVR Certificate shall thenceforth
represent that number of adjusted CVRs necessary to reflect such subdivision or
combination, and reflect the adjusted Discounted Target Price, Target Price, the
Early Redemption Price and the Minimum Price.

     (l)  If the Current Market Value of the Shares during any 20 consecutive
trading days in the Valuation Period is greater than or equal to the Target
Price, the CVRs will automatically be extinguished without further consideration
or action by the Company or the Holders (the "Automatic Extinguishment") and all
obligation of the Company under this Agreement shall terminate and be of no
further force or effect; provided that the Company shall (i) promptly prepare a
certificate stating that an Automatic Extinguishment has occurred and briefly
stating the facts accounting for such Automatic Extinguishment, (ii) promptly
file with the Trustee a copy of such certificate and (iii) mail a brief summary
thereof to each Holder.

Section 302.  Registrable Form.

     The CVRs shall be issuable only in registered form.

Section 303.  Execution, Authentication, Delivery and Dating.

     The CVRs shall be executed on behalf of the Company by its chairman or vice
chairman of the Board of Directors or its president or any vice president or its
treasurer,

                                       21
<PAGE>

under its corporate seal, which may, but need not, be attested. The signature of
any of these officers on the CVRs may be manual or facsimile.

     CVRs bearing the manual or facsimile signatures of individuals who were at
any time the proper officers of the Company shall bind the Company,
notwithstanding that such individuals or any of them have ceased to hold such
offices prior to the authentication and delivery of such CVRs or did not hold
such offices at the date of such CVRs.

     At any time and from time to time after the execution and delivery of this
Agreement, the Company may deliver CVRs executed by the Company to the Trustee
for authentication, together with a Company Order for the authentication and
delivery of such CVRs; and the Trustee in accordance with such Company Order
shall authenticate and deliver such CVRs as provided in this Agreement and not
otherwise.

     Each CVR shall be dated as of the date of its authentication.

     No CVR shall be entitled to any benefit under this Agreement or be valid or
obligatory for any purpose unless there appears on such CVR a certificate of
authentication substantially in the form provided for herein duly executed by
the Trustee by manual signature of an authorized officer, and such certificate
upon any CVR shall be conclusive evidence, and the only evidence, that such CVR
has been duly authenticated and delivered hereunder and that the Holder is
entitled to the benefits of this Agreement.

Section 304.  Temporary CVRs.

     Pending the preparation of definitive CVRs, the Company may execute, and
upon Company Order the Trustee shall authenticate and deliver, temporary CVRs
which are printed, lithographed, typewritten, mimeographed or otherwise
produced, substantially of the tenor of the definitive CVRs in lieu of which
they are issued and with such appropriate insertions, omissions, substitutions
and other variations as the officers executing such CVRs may determine with the
concurrence of the Trustee.  Temporary CVRs may contain such reference to any
provisions of this Agreement as may be appropriate.  Every temporary CVR shall
be executed by the Company and be authenticated by the Trustee upon the same
conditions and in substantially the same manner, and with like effect, as the
definitive CVRs.

     If temporary CVRs are issued, the Company will cause definitive CVRs to be
prepared without unreasonable delay.  After the preparation of definitive CVRs,
the temporary CVRs shall be exchangeable for definitive CVRs upon surrender of
the temporary CVRs at the office or agency of the Company designated for such
purpose pursuant to Section 702, without charge to the Holder.

     Upon surrender for cancellation of any one or more temporary CVRs the
Company shall execute and the Trustee shall authenticate and deliver in exchange
therefor a like amount of definitive CVRs.  Until so exchanged, the temporary
CVRs

                                       22
<PAGE>

shall in all respects be entitled to the same benefits under this Agreement as
definitive CVRs.

Section 305.  Registration, Registration of Transfer and Exchange.

     The Company shall cause to be kept at the Corporate Trust Office of the
Trustee a register (the register maintained in such office and in any other
office or agency designated pursuant to Section 702 being herein sometimes
referred to as the "Security Register") in which, subject to such reasonable
regulations as it may prescribe, the Company shall provide for the registration
of CVRs and of transfers of CVRs.  The Trustee is hereby initially appointed
"Security Registrar" for the purpose of registering CVRs and transfers of CVRs
as herein provided.

     Upon surrender for registration of transfer of any CVR at the office or
agency of the Company designated pursuant to Section 702, the Company shall
execute, and the Trustee shall authenticate and deliver, in the name of the
designated transferee or transferees, one or more new CVR Certificates
representing the same aggregate number of CVRs represented by the CVR
Certificate so surrendered that are to be transferred and the Company shall
execute and the Trustee shall authenticate and deliver, in the name of the
transferor, one or more new CVR Certificates represented by such CVR Certificate
that are not to be transferred.

     At the option of the Holder, CVR Certificates may be exchanged for other
CVR Certificates that represent in the aggregate the same number of CVRs as the
CVR Certificates surrendered at such office or agency.  Whenever any CVR
Certificates are so surrendered for exchange, the Company shall execute, and the
Trustee shall authenticate and deliver, the CVR Certificates that the Holder
making the exchange is entitled to receive.

     All CVRs issued upon any registration of transfer or exchange of CVRs shall
be the valid obligations of the Company, evidencing the same right, and entitled
to the same benefits under this Agreement, as the CVRs surrendered upon such
registration of transfer or exchange.

     Every CVR presented or surrendered for registration of transfer or for
exchange shall (if so required by the Company or the Security Registrar) be duly
endorsed, or be accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar, duly executed by the
Holder thereof or his attorney duly authorized in writing.

     No service charge shall be made for any registration of transfer or
exchange of CVRs, but the Company may require payment of a sum sufficient to
cover any tax or other governmental charge that may be imposed in connection
with any registration of transfer or exchange of CVRs, other than exchanges
pursuant to Section 304 or not involving any transfer.

                                       23
<PAGE>

Section 306.  Mutilated, Destroyed, Lost and Stolen CVRs.

     If (a) any mutilated CVR is surrendered to the Trustee or (b) the Company
and the Trustee receive evidence to their satisfaction of the destruction, loss
or theft of any CVR, and there is delivered to the Company and the Trustee such
security or indemnity as may be required by them to save each of them harmless,
then, in the absence of notice to the Company or the Trustee that such CVR has
been acquired by a bona fide purchaser, the Company shall execute and upon its
written request the Trustee shall authenticate and deliver, in exchange for any
such mutilated CVR or in lieu of any such destroyed, lost or stolen CVR, a new
CVR Certificate of like tenor and amount of CVRs, bearing a number not
contemporaneously outstanding.

     In case any such mutilated, destroyed, lost or stolen CVR has become or is
to become due and payable within 15 days, the Company in its discretion may,
instead of issuing a new CVR Certificate, pay such CVR on the Maturity Date, the
Early Redemption Payment Date, the Disposition Payment Date or the Default
Payment Date, as the case may be.

     Upon the issuance of any new CVRs under this Section, the Company may
require the payment of a sum sufficient to cover any tax or other governmental
charge that may be imposed in relation thereto and any other expenses (including
the fees and expenses of the Trustee) connected therewith.

     Every new CVR issued pursuant to this Section in lieu of any destroyed,
lost or stolen CVR shall constitute an original additional contractual
obligation of the Company, whether or not the destroyed, lost or stolen CVR
shall be at any time enforceable by anyone, and shall be entitled to all
benefits of this Agreement equally and proportionately with any and all other
CVRs duly issued hereunder.

     The provisions of this Section are exclusive and shall preclude (to the
extent lawful) all other rights and remedies with respect to the replacement or
payment of mutilated, destroyed, lost or stolen CVRs.

Section 307.  Presentation of CVR Certificate.

     Payment of any amounts on the CVRs shall be made only upon presentation by
the Holder thereof at the office or agency of the Company maintained for that
purpose in the Borough of Manhattan in the City of New York and at any other
office or agency maintained by the Company for such purpose.  Such payment shall
be made, either, in the Company's sole discretion, (i) in Cash or (ii) Stock.
The Holder of the CVRs shall furnish to the Company such forms, certificates, or
other information as the Company may request to establish the legal entitlement
of such Holder to an exemption from withholding taxes. In the event the Company
does not receive such forms, certificates, or other evidence establishing a
Holder's legal entitlement to exemption from withholding tax, then all payments
and disbursements to be made by the Company pursuant to this Agreement or the
CRSs shall be reduced by and subject to withholding taxes. The Company shall
have no obligation to reimburse, equalize or compensate a Holder or other person
for withholding taxes.

Section 308.  Persons Deemed Owners.

     Prior to the time of due presentment for registration of transfer, the
Company, the Trustee and any agent of the Company or the Trustee may treat the
Person in whose name any CVR is registered as the owner of such CVR for the
purpose of receiving payment on

                                       24
<PAGE>

such CVR and for all other purposes whatsoever, whether or not such CVR be
overdue, and neither the Company, the Trustee nor any agent of the Company or
the Trustee shall be affected by notice to the contrary.
Section 309.  Cancellation.

     All CVRs surrendered for payment, registration of transfer or exchange
shall, if surrendered to any Person other than the Trustee, be delivered to the
Trustee and shall be promptly cancelled by it.  The Company may at any time
deliver to the Trustee for cancellation any CVRs previously authenticated and
delivered hereunder which the Company may have acquired in any manner
whatsoever, and all CVRs so delivered shall be promptly cancelled by the
Trustee.  No CVRs shall be authenticated in lieu of or in exchange for any CVRs
cancelled as provided in this Section, except as expressly permitted by this
Agreement.  All cancelled CVRs held by the Trustee shall be disposed of as
directed by a Company Order.

                                  ARTICLE FOUR

                                  THE TRUSTEE

Section 401.  Certain Duties and Responsibilities.

     (a)  With respect to the Holders of CVRs issued hereunder, the Trustee,
prior to the occurrence of an Event of Default with respect to the CVRs and
after the curing or waiving of all Events of Default which may have occurred,
undertakes to perform such duties and only such duties as are specifically set
forth in this Agreement.  In case an Event of Default with respect to the CVRs
has occurred (which has not been cured or waived), the Trustee shall exercise
such of the rights and powers vested in it by this Agreement, and use the same
degree of care and skill in their exercise, as a prudent man would exercise or
use under the circumstances in the conduct of his own affairs.

     (b)  In the absence of bad faith on its part, prior to the occurrence of an
Event of Default and after the curing or waiving of all such Events of Default
which may have occurred, the Trustee may conclusively rely, as to the truth of
the statements and the correctness of the opinions expressed therein, upon
certificates or opinions furnished to the Trustee and conforming to the
requirements of this Agreement; but in the case of any such certificates or
opinions which by any provision hereof are specifically required to be furnished
to the Trustee, the Trustee shall be under a duty to examine the same to
determine whether or not they conform to the requirements of this Agreement.

     (c)  No provision of this Agreement shall be construed to relieve the
Trustee from liability for its own negligent action, its own negligent failure
to act, or its own willful misconduct, except that

                                       25
<PAGE>

          (1)  this Subsection (c) shall not be construed to limit the effect of
     Subsections (a) and (b) of this Section;

          (2)  the Trustee shall not be liable for any error of judgment made in
     good faith by a Responsible Officer, unless it shall be proved that the
     Trustee was negligent in ascertaining the pertinent facts;

          (3)  no provision of this Agreement shall require the Trustee to
     expend or risk its own funds or otherwise incur any financial liability in
     the performance of any of its duties hereunder, or in the exercise of any
     of its rights or powers, if it shall have reasonable grounds for believing
     that repayment of such funds or adequate indemnity against such risk or
     liability is not reasonably assured to it; and

          (4)  the Trustee shall not be liable with respect to any action taken
     or omitted to be taken by it in good faith in accordance with the direction
     of the Holders pursuant to Section 809 relating to the time, method and
     place of conducting any proceeding for any remedy available to the Trustee,
     or exercising any trust or power conferred upon the Trustee, under this
     Agreement.

     (d)  Whether or not therein expressly so provided, every provision of this
Agreement relating to the conduct or affecting the liability of or affording
protection to the Trustee shall be subject to the provisions of this Section.

Section 402.  Certain Rights of Trustee.

     The Trustee undertakes to perform such duties and only such duties as are
specifically set forth in this Agreement, and no implied covenants or
obligations shall be read into this Agreement against the Trustee.  Subject to
the provisions of Trust Indenture Act Sections 315(a) through 315(d) and Section
401 hereof:

          (a)  the Trustee may rely and shall be protected in acting or
     refraining from acting upon any resolution, certificate, statement,
     instrument, opinion, report, notice, request, direction, consent, order,
     bond, debenture, note, other evidence of indebtedness or other paper or
     document believed by it to be genuine and to have been signed or presented
     by the proper party or parties;

          (b)  any request or direction of the Company mentioned herein shall be
     sufficiently evidenced by a Company Request or Company Order and any
     resolution of the Board of Directors may be sufficiently evidenced by a
     Board Resolution;

          (c)  whenever in the administration of this Agreement the Trustee
     shall deem it desirable that a matter be proved or established prior to
     taking, suffering or omitting any action hereunder, the Trustee (unless
     other evidence be herein

                                       26
<PAGE>

     specifically prescribed) may, in the absence of bad faith on its part, rely
     upon an Officer's Certificate;

          (d)  the Trustee may consult with counsel and the written advice of
     such counsel or any Opinion of Counsel shall be full and complete
     authorization and protection in respect of any action taken, suffered or
     omitted by it hereunder in good faith and in reliance thereon;

          (e)  the Trustee shall be under no obligation to exercise any of the
     rights or powers vested in it by this Agreement at the request or direction
     of any of the Holders pursuant to this Agreement, unless such Holders shall
     have offered to the Trustee reasonable security or indemnity against the
     costs, expenses and liabilities which might be incurred by it in compliance
     with such request or direction;

          (f)  the Trustee shall not be bound to make any investigation into the
     facts or matters stated in any resolution, certificate, statement,
     instrument, opinion, report, notice, request, consent, order, approval,
     appraisal, bond, debenture, note, coupon, security, or other paper or
     document unless requested in writing to do so by the Holders of not less
     than a majority in aggregate number of the CVRs then Outstanding; provided
     that, if the payment within a reasonable time to the Trustee of the costs,
     expenses or liabilities likely to be incurred by it in the making of such
     investigation is, in the opinion of the Trustee, not reasonably assured to
     the Trustee by the security afforded to it by the terms of this Agreement,
     the Trustee may require reasonable indemnity against such expenses or
     liabilities as a condition to proceeding; the reasonable expenses of every
     such investigation shall be paid by the Company or, if paid by the Trustee
     or any predecessor Trustee, shall be repaid by the Company upon demand;

          (g)  the Trustee may execute any of the trusts or powers hereunder or
     perform any duties hereunder either directly or by or through agents or
     attorneys and the Trustee shall not be responsible for any misconduct or
     negligence on the part of any agent or attorney appointed with due care by
     it hereunder;

          (h)  the permissive rights of the Trustee to do things enumerated in
     this Indenture shall not be construed as a duty and the Trustee shall be
     liable for its negligence, bad faith or willful misconduct; and

          (i)  except for (i) a default under Section 801(a) and (ii) any other
     event of which the Trustee has "actual knowledge," which event, with the
     giving of notice or the passage of time or both, would constitute an Event
     of Default, the Trustee shall not be deemed to have notice of any default
     or event unless specifically notified in writing of such event by the
     Company or the Holders of not less than 25% in aggregate number of CVRs
     Outstanding; as used herein, the term "actual knowledge" means the actual
     fact or statement of knowing, without any duty to make any investigation
     with regard thereto.

                                       27
<PAGE>

     No provision of this Agreement shall require the Trustee to expend or risk
its own funds or otherwise incur any financial liability in the performance of
any of its duties hereunder, or in the exercise of any of its rights or powers,
if it shall have reasonable grounds for believing that repayment of such funds
or adequate indemnity against such risk or liability is not reasonably assured
to it.

Section 403.  Not Responsible for Recitals or Issuance of CVRs.

     The recitals contained herein and in the CVRs, except the Trustee's
certificates of authentication, shall be taken as the statements of the Company,
and the Trustee assumes no responsibility for their correctness.  The Trustee
makes no representations as to the validity or sufficiency of this Agreement or
of the CVRs.  The Trustee shall not be accountable for the use or application by
the Company of CVRs or the proceeds thereof.

Section 404.  May Hold CVRs.

     The Trustee, any Paying Agent, Security Registrar or any other agent of the
Company, in its individual or any other capacity, may become the owner or
pledgee of CVRs, and, subject to Sections 407 and 401, may otherwise deal with
the Company with the same rights it would have if it were not Trustee, Paying
Agent, Security Registrar or such other agent.

Section 405.  Money Held in Trust.

     Money held by the Trustee in trust hereunder need not be segregated from
other funds except to the extent required by law.  The Trustee shall be under no
liability for interest on any money received by it hereunder.

Section 406.  Compensation, Reimbursement and Indemnification of the Trustee.

     The Company agrees

          (a)  to pay to the Trustee from time to time reasonable compensation
     for all services rendered by it hereunder (which compensation shall not be
     limited by any provision of law in regard to the compensation of a trustee
     of an express trust);

          (b)  except as otherwise expressly provided herein, to reimburse the
     Trustee upon its request for all reasonable expenses, disbursements and
     advances incurred or made by the Trustee in accordance with any provision
     of this Agreement (including the reasonable compensation and the expenses
     and disbursements of its agents and counsel), except any such expense,
     disbursement or advance as may be attributable to its negligence or bad
     faith; and

          (c)  to indemnify the Trustee for, and to hold it harmless against,
     any loss, liability or expense incurred without negligence or bad faith on
     its part, arising out

                                       28
<PAGE>

     of or in connection with the acceptance or administration of this trust,
     including the costs and expenses of defending itself against any claim or
     liability in connection with the exercise or performance of any of its
     powers or duties hereunder, including the enforcement of this Section 406.

     When the Trustee incurs expenses or renders services after a Default
specified in Section 801(c) or 801(d) occurs, the reasonable expenses and the
compensation for services (including the reasonable fees and expenses of its
agents and counsel) are intended to constitute expenses of administration under
any bankruptcy law.

Section 407.  Disqualification; Conflicting Interests.

     The Trustee shall be subject to the provisions of Section 310(b) of the
Trust Indenture Act during the period of time provided for therein.  Nothing
herein shall prevent the Trustee from filing with the Commission the application
referred to in the penultimate paragraph of Section 310(b) of the Trust
Indenture Act.

Section 408.  Corporate Trustee Required; Eligibility.

     There shall at all times be a Trustee hereunder which shall be a
corporation organized and doing business under the laws of the United States of
America or of any State, authorized under such laws to exercise corporate trust
powers, having a combined capital and surplus of at least $50,000,000, subject
to supervision or examination by Federal or State authority and, to the extent
there is such an institution eligible and willing to serve, having an office or
agency in the City of New York, the City of Richmond, Virginia or the City of
Charlotte, North Carolina.  If such corporation publishes reports of condition
at least annually pursuant to law or to the requirements of the aforesaid
supervising or examining authority, then, for the purposes of this Section, the
combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so published.  If at any time the Trustee shall cease to be eligible in
accordance with the provisions of this Section, it shall resign immediately in
the manner and with the effect hereinafter specified in this Article.

Section 409.  Resignation and Removal; Appointment of Successor.

     (a)  No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee under Section 410.

     (b)  The Trustee, or any trustee or trustees hereafter appointed, may
resign at any time by giving written notice thereof to the Company.  If an
instrument of acceptance by a successor Trustee shall not have been delivered to
the Trustee within 30 days after the giving of such notice of resignation, the
resigning Trustee may petition any court of competent jurisdiction for the
appointment of a successor Trustee.

                                       29
<PAGE>

     (c)  The Trustee may be removed at any time by (i) the Company, by a Board
Resolution or, (ii) an Act of the Holders of a majority of the Outstanding CVRs,
delivered to the Trustee and to the Company.

     (d)  If at any time:

          (1)  the Trustee shall fail to comply with Section 407 after written
     request therefor by the Company or by any Holder who has been a bona fide
     Holder of a CVR for at least six months,

          (2)  the Trustee shall cease to be eligible under Section 408 and
     shall fail to resign after written request therefor by the Company or by
     any such Holder, or

          (3)  the Trustee shall become incapable of acting or shall be adjudged
     bankrupt or insolvent, or a receiver of the Trustee or of its property
     shall be appointed, or any public officer shall take charge or control of
     the Trustee or of its property or affairs for the purpose of
     rehabilitation, conservation or liquidation, then, in any case, (i) the
     Company by a Board Resolution may remove the Trustee, or (ii) the Holder of
     any CVR who has been a bona fide Holder of a CVR for at least six months
     may, on behalf of himself and all others similarly situated, petition any
     court of competent jurisdiction for the removal of the Trustee and the
     appointment of a successor Trustee.

     (e)  If the Trustee shall resign, be removed or become incapable of acting,
or if a vacancy shall occur in the office of Trustee for any reason, the
Company, by a Board Resolution, shall promptly appoint a successor Trustee.  If,
within one year after such resignation, removal or incapability, or the
occurrence of such vacancy, a successor Trustee shall be appointed by Act of the
Holders of a majority of the Outstanding CVRs delivered to the Company and the
retiring Trustee, the successor Trustee so appointed shall, forthwith upon its
acceptance of such appointment in accordance with Section 410, become the
successor Trustee and supersede the successor Trustee appointed by the Company.
If no successor Trustee shall have been so appointed by the Company or the
Holders of the CVRs and so accepted appointment, the Holder of any CVR who has
been a bona fide Holder for at least six months may on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
appointment of a successor Trustee.

     (f)  The Company shall give notice of each resignation and each removal of
the Trustee and each appointment of a successor Trustee by mailing written
notice of such event by first-class mail, postage prepaid, to the Holders of
CVRs as their names and addresses appear in the Security Register.  Each notice
shall include the name of the successor Trustee and the address of its Corporate
Trust Office.  If the Company fails to send such notice within ten days after
acceptance of appointment by a successor Trustee, the successor Trustee shall
cause the notice to be mailed at the expense of the Company.

Section 410.  Acceptance of Appointment by Successor.

                                       30
<PAGE>

     Every successor Trustee appointed hereunder shall execute, acknowledge and
deliver to the Company and to the retiring Trustee an instrument accepting such
appointment, and thereupon the resignation or removal of the retiring Trustee
shall become effective and such successor Trustee, without any further act, deed
or conveyance, shall become vested with all the rights, powers, trusts and
duties of the retiring Trustee; but, on request of the Company or the successor
Trustee, such retiring Trustee shall, upon payment of its charges, execute and
deliver an instrument transferring to such successor Trustee all the rights,
powers and trusts of the retiring Trustee, and shall duly assign, transfer and
deliver to such successor Trustee all property and money held by such retiring
Trustee hereunder.  Upon request of any such successor Trustee, the Company
shall execute any and all instruments for more fully and certainly vesting in
and confirming to such successor Trustee all such rights, powers and trusts.

     No successor Trustee shall accept its appointment unless at the time of
such acceptance such successor Trustee shall be qualified and eligible under
this Article.

Section 411.  Merger, Conversion, Consolidation or Succession to Business.

     Any corporation into which the Trustee may be merged or converted or with
which it may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Trustee shall be a party, or any
corporation succeeding to all or substantially all of the corporate trust
business of the Trustee, shall be the successor of the Trustee hereunder,
provided such corporation shall be otherwise qualified and eligible under this
Article, without the execution or filing of any paper or any further act on the
part of any of the parties hereto.  In case any CVRs shall have been
authenticated, but not delivered, by the Trustee then in office, any successor
by merger, conversion or consolidation to such authenticating Trustee may adopt
such authentication and deliver the CVRs so authenticated with the same effect
as if such successor Trustee had itself authenticated such CVRs; and such
certificate shall be fully effective, provided that the right to adopt the
certificate of authentication of any predecessor Trustee shall apply only to its
successor or successors by merger, conversion or consolidation.

                                  ARTICLE FIVE

               HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY'

Section 501.  Company to Furnish Trustee Names and Addresses of Holders.

     The Company will furnish or cause to be furnished to the Trustee (a)
semiannually, not later than [DATE 6 MOS. AFTER DATE OF CVR] and [DATE 12 MOS.
AFTER DATE OF CVR], a list, in such form as the Trustee may reasonably require,
of the names and addresses of the Holders as of  [ DATE FIVE MONTHS 15 DAYS
AFTER DATE OF CVR] and [DATE ELEVEN MONTHS 15 DAYS AFTER DATE OF CVR],
respectively, and (b) at such times as the Trustee may request in

                                       31
<PAGE>

writing, within 30 days after receipt by the Company of any such request, a
list, in such form as the Trustee may reasonably require, of the names and the
addresses of the Holders as of a date not more than 15 days prior to the time
such list is furnished; provided, however, that, if and so long as the Trustee
shall be the Security Registrar, no such list need be furnished.

Section 502.  Preservation of Information; Communications to Holders.

     (a)  The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in Section 501 and the names and
addresses of Holders received by the Trustee in its capacity as Security
Registrar.  The Trustee may destroy any list furnished to it as provided in
Section 501 upon receipt of a new list so furnished.

     (b)  If three or more Holders (hereinafter referred to as "applicants")
apply in writing to the Trustee, and furnish to the Trustee reasonable proof
that each such applicant has owned a CVR for a period of at least six months
preceding the date of such application, and such application states that the
applicants desire to communicate with other Holders with respect to their rights
under this Agreement or under the CVRs and is accompanied by a copy of the form
of proxy or other communication which such applicants propose to transmit, then
the Trustee shall, within five Business Days after the receipt of such
application at its election, either

          (1)  afford such applicants access to the information preserved at the
     time by the Trustee in accordance with Section 502(a), or

          (2)  inform such applicants as to the approximate number of Holders
     whose names and addresses appear in the information preserved at the time
     by the Trustee in accordance with Section 502(a), and as to the approximate
     cost of mailing to such Holders the form of proxy or other communication,
     if any, specified in such application.

     If the Trustee shall elect not to afford such applicants access to such
information, the Trustee shall, upon the written request of such applicants,
mail to each Holder whose name and address appear in the information preserved
at the time by the Trustee in accordance with Section 502(a), a copy of the form
of proxy or other communication which is specified in such request, with
reasonable promptness after a tender to the Trustee of the material to be mailed
and of payment, or provision for the payment, of the reasonable expenses of
mailing, unless within five days after such tender, the Trustee shall mail to
such applicants and file with the Commission, together with a copy of the
material to be mailed, a written statement to the effect that, in the opinion of
the Trustee, such mailing would be contrary to the best interests of the Holders
or would be in violation of applicable law.  Such written statement shall
specify the basis of such opinion.  If the Commission, after opportunity for a
hearing upon the objections specified in the written statement so filed, shall
enter an order refusing to sustain any of such objections or if, after the entry
of an order sustaining one or more of such objections, the

                                       32
<PAGE>

Commission shall find, after notice and opportunity for hearing, that all the
objections so sustained have been met and shall enter an order so declaring, the
Trustee shall mail copies of such material to all such Holders with reasonable
promptness after the entry of such order and the renewal of such tender;
otherwise the Trustee shall be relieved of any obligation or duty to such
applicants respecting their application.

     (c)  Every Holder of CVRs, by receiving and holding the same, agrees with
the Company and the Trustee that neither the Company nor the Trustee shall be
held accountable by reason of the disclosure of any such information as to the
names and addresses of the Holders in accordance with Section 502(b), regardless
of the source from which such information was derived, and that the Trustee
shall not be held accountable by reason of mailing any material pursuant to a
request made under Section 502(b).

Section 503.  Reports by Trustee.

     Within 60 days after July 15 of each year, commencing with the July 15
occurring after the initial issuance of CVRs hereunder, the Trustee shall
transmit by mail to the Holders of CVRs, in the manner and to the extent
provided in Section 313(c) of the Trust Indenture Act, and to the Company a
brief report dated as of such July 15 which satisfies the requirements of
Section 313(a) of the Trust Indenture Act.

Section 504.  Reports by Company.

     The Company shall:

          (a)  file with the Trustee, within 15 days after the date on which the
     Company is required to file the same with the Commission, copies of the
     annual reports and of the information, documents and other reports (or
     copies of such portions of any of the foregoing as the Commission may from
     time to time by rules and regulations prescribe) which the Company may be
     required to file with the Commission pursuant to Section 13 or Section
     15(d) of the Exchange Act; or, if the Company is not required to file
     information, documents or reports pursuant to either of such sections, then
     to file with the Trustee and the Commission, in accordance with rules and
     regulations prescribed from time to time by the Commission, such of the
     supplementary and periodic information, documents and reports which may be
     required pursuant to Section 13 of the Exchange Act in respect of a
     security listed and registered on a national securities exchange as may be
     prescribed from time to time in such rules and regulations; and

          (b)  file with the Trustee and the Commission, in accordance with the
     rules and regulations prescribed from time to time by the Commission, such
     additional information, documents and reports with respect to compliance by
     the Company with the conditions and covenants of this Agreement as may be
     required from time to time by such rules and regulations.

                                       33
<PAGE>

     The Trustee shall transmit by mail to all Holders, as their names and
addresses appear in the Security Register, within 30 days after the filing
thereof with the Trustee, such summaries of any information, documents and
reports required to be filed by the Company pursuant to Subsections (a) and (b)
of this Section as may be required by rules and regulations prescribed from time
to time by the Commission.

                                  ARTICLE SIX

                                   AMENDMENTS

Section 601.  Amendments Without Consent of Holders.

     Without the consent of any Holders, the Company, when authorized by a Board
Resolution, and the Trustee, at any time and from time to time, may enter into
one or more amendments hereto, in form satisfactory to the Trustee, for any of
the following purposes:

          (a)  to convey, transfer, assign, mortgage or pledge to the Trustee as
     security for the CVRs any property or assets;

          (b)  to evidence the succession of another Person to the Company, and
     the assumption by any such successor of the covenants of the Company herein
     and in the CVRs;

          (c)  to add to the covenants of the Company such further covenants,
     restrictions, conditions or provisions as its Board of Directors and the
     Trustee shall consider to be for the protection of the Holders of CVRs, and
     to make the occurrence, or the occurrence and continuance, of a default in
     any such additional covenants, restrictions, conditions or provisions an
     Event of Default permitting the enforcement of all or any of the several
     remedies provided in this Agreement as herein set forth; provided that in
     respect of any such additional covenant, restriction, condition or
     provision such amendment may provide for a particular period of grace after
     default (which period may be shorter or longer than that allowed in the
     case of other defaults) or may provide for an immediate enforcement upon
     such an Event of Default or may limit the remedies available to the Trustee
     upon such an Event of Default or may limit the right of the Holders of a
     majority in aggregate principal amount of the CVRs to waive such an Event
     of Default; or

          (d)  to cure any ambiguity, to correct or supplement any provision
     herein which may be defective or inconsistent with any other provision
     herein, or to make any other provisions with respect to matters or
     questions arising under this Agreement; provided that in each case, such
     provisions shall not adversely affect the interests of the Holders.

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Section 602.  Amendments with Consent of Holders.

     With the consent of the Holders of not less than a majority of the
Outstanding CVRs as required to amend the Agreement in accordance with the Trust
Indenture Act, by Act of said Holders delivered to the Company and the Trustee,
the Company, when authorized by a Board Resolution, and the Trustee may enter
into one or more amendments hereto for the purpose of adding any provisions to
or changing in any manner or eliminating any of the provisions of this Agreement
or of modifying in any manner the rights of the Holders under this Agreement;
provided that no such amendment shall, without the consent of the Holder of each
Outstanding CVR affected thereby:

          (a)  modify the definition of Maturity Date, Disposition Payment Date,
     Default Payment Date, Early Redemption Payment, Early Redemption
     Determination Date, Current Market Value, Valuation Period, Minimum Price,
     Discounted Target Price, Target Price, Default Amount or Default Interest
     Rate or modify Section 301(k) or otherwise extend the maturity of the CVRs
     or reduce the amounts payable in respect of the CVRs;

          (b)  reduce the amount of the Outstanding CVRs, the consent of whose
     Holders is required for any such amendment; or

          (c)  modify any of the provisions of this Section, except to increase
     any such percentage or to provide that certain other provisions of this
     Agreement cannot be modified or waived without the consent of the Holder of
     each CVR affected thereby.

     It shall not be necessary for any Act of Holders under this Section to
approve the particular form of any proposed amendment, but it shall be
sufficient if such Act shall approve the substance thereof.

     Promptly after the execution by the Company and the Trustee of any
amendment pursuant to the provisions of this Section, the Company shall mail a
notice thereof by first class mail to the Holders of CVRs at their addresses as
they shall appear on the Security Register, setting forth in general terms the
substance of such amendment.  Any failure of the Company to mail such notice, or
any defect therein, shall not, however, in any way impair or affect the validity
of any such amendment.

Section 603.  Execution of Amendments.

     In executing any amendment permitted by this Article, the Trustee shall be
entitled to receive, and (subject to Section 401) shall be fully protected in
relying upon, an Opinion of Counsel stating that the execution of such amendment
is authorized or permitted by this Agreement.  The Trustee may, but shall not be
obligated to, enter into any such amendment which affects the Trustee's own
rights, duties or immunities under this Agreement or otherwise.

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Section 604.  Effect of Amendments.

     Upon the execution of any amendment under this Article, this Agreement
shall be modified in accordance therewith, and such amendment shall form a part
of this Agreement for all purposes; and every Holder of CVRs theretofore or
thereafter authenticated and delivered hereunder shall be bound thereby.

Section 605.  Conformity with Trust Indenture Act.

     Every amendment executed pursuant to this Article shall conform to the
requirements of the Trust Indenture Act as then in effect.

Section 606.  Reference in CVRs to Amendments.

     CVRs authenticated and delivered after the execution of any amendment
pursuant to this Article may, and shall if required by the Trustee, bear a
notation in form approved by the Trustee as to any matter provided for in such
amendment.  If the Company shall so determine, new CVRs so modified as to
conform, in the opinion of the Trustee and the Board of Directors, to any such
amendment may be prepared and executed by the Company and authenticated and
delivered by the Trustee in exchange for Outstanding CVRs.

                                 ARTICLE SEVEN

                                   COVENANTS

Section 701.  Payment of Amounts, if Any, to Holders.

     The Company will duly and punctually pay the amounts, if any, in the manner
provided for in Section 307 on the CVRs in accordance with the terms of the CVRs
and this Agreement.

Section 702.  Maintenance of Office or Agency.

     As long as any of the CVRs remain Outstanding, the Company will maintain in
the Borough of Manhattan, the City of New York, an office or agency where CVRs
may be presented or surrendered for payment. The Company also will maintain in
the Borough of Manhattan, the City of New York, the City of Richmond, Virginia,
or the City of Charlotte, North Carolina, an office or agency (i) where CVRs may
be surrendered for registration of transfer or exchange and (ii) where notices
and demands to or upon the Company in respect of the CVRs and this Agreement may
be served.  The Company hereby initially designates the office of
____________________ at ____________ as the office or agency of the Company
where CVRs may be presented for payment, and the _________________ as the office
or agency where CVRs may be surrendered for registration of transfer or exchange
and where such notices or demands

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<PAGE>

may be served, in each case, unless the Company shall designate and maintain
some other office or agency for one or more of such purposes. The Company will
give prompt written notice to the Trustee of any change in the location of any
such office or agency. If at any time the Company shall fail to maintain any
such required office or agency or shall fail to furnish the Trustee with the
address thereof, such presentations, surrenders, notices and demands may be made
or served at the __________________ of the Trustee, and the Company hereby
appoints the Trustee as its agent to receive all such presentations, surrenders,
notices and demands.

     The Company may from time to time designate one or more other offices or
agencies (in or outside of the City of New York) where the CVRs may be presented
or surrendered for any or all such purposes, and may from time to time rescind
such designation; provided, however, that no such designation or rescission
shall in any manner relieve the Company of its obligations as set forth in the
preceding paragraph. The Company will give prompt written notice to the Trustee
of any such designation or rescission and any change in the location of any such
office or agency.

Section 703.  Money for CVR Payments to Be Held in Trust.

     If the Company shall at any time act as its own Paying Agent, it will, on
or before the Maturity Date, the Early Redemption Payment Date, the Disposition
Payment Date or the Default Payment Date, as the case may be, segregate and hold
in trust for the benefit of the Persons entitled thereto a sum sufficient to pay
the amounts, if any, so becoming due until such sums shall be paid to such
Persons or otherwise disposed of as herein provided, and will promptly notify
the Trustee of its action or failure so to act.

     Whenever the Company shall have one or more Paying Agents for the CVRs, it
will, on or before the Maturity Date, the Early Redemption Payment Date, the
Disposition Payment Date or the Default Payment Date, as the case may be,
deposit with a Paying Agent a sum in same day funds sufficient to pay the
amount, if any, so becoming due, such sum to be held in trust for the benefit of
the Persons entitled to such amount, and (unless such Paying Agent is the
Trustee) the Company will promptly notify the Trustee of such action or any
failure so to act.

     The Company will cause each Paying Agent other than the Trustee to execute
and deliver to the Trustee an instrument in which such Paying Agent shall agree
with the Trustee, subject to the provisions of this Section, that (A) such
Paying Agent will hold all sums held by it for the payment of any amount payable
on CVRs in trust for the benefit of the Persons entitled thereto until such sums
shall be paid to such Persons or otherwise disposed of as herein provided and
(B) that it will give the Trustee notice of any failure by the Company (or by
any other obligor on the CVRs) to make any payment on the CVRs when the same
shall be due and payable.

     Any money (or securities of the Company) deposited with the Trustee or any
Paying Agent, or then held by the Company, in trust for the payment on any CVRs
and remaining unclaimed for one year after the Maturity Date, the Early
Redemption

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<PAGE>

Payment Date, the Disposition Payment Date or the Default Payment Date, as the
case may be, shall be paid to the Company on Company Request, or (if then held
by the Company) shall be discharged from such trust; and the Holder of such CVR
shall thereafter, as an unsecured general creditor, look only to the Company for
payment thereof and all liability of the Trustee or such Paying Agent with
respect to such trust money (or securities of the Company) shall thereupon
cease.

Section 704.  Certain Purchases and Sales.

     The Company will not, and will not permit any of its subsidiaries or
controlled Affiliates or Steven A. Markel, Anthony F. Markel or Alan I.
Kirshner, to purchase any Shares on any day during the period commencing 10
trading days before the Valuation Period with respect to the Maturity Date and
ending on the Maturity Date, except (x) in privately negotiated transactions
that are not reported to any exchange (other than as a result of being disclosed
in a filing with the Commission that is also required to be filed with such
exchange), (y) with respect to employee benefit plans and other incentive
compensation arrangements in the ordinary course of business and (z) purchases
in compliance with Rule 10b-18 promulgated under the Exchange Act.

Section 705.  Written Statement to Trustee.

     The Company will deliver to the Trustee, within 120 days after the end of
each fiscal year, a brief certificate from the principal executive officer,
principal financial officer or principal accounting officer as to his or her
knowledge of the Company's compliance with all conditions and covenants under
this Agreement.  For purposes of this Section, such compliance shall be
determined without regard to any period of grace or requirement of notice under
this Agreement.

                                 ARTICLE EIGHT

            REMEDIES OF THE TRUSTEE AND HOLDERS ON EVENT OF DEFAULT

Section 801.  Event of Default Defined; Acceleration of Maturity; Waiver of
Default.

     "Event of Default", with respect to CVRs, means any of the following events
which shall have occurred and be continuing (whatever the reason for such Event
of Default and whether it shall be voluntary or involuntary or be effected by
operation of law  or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body):

          (a)  default in the payment of all or any part of the amounts payable
     in respect of any of the CVRs as and when the same shall become due and
     payable following the Maturity Date, the Disposition Payment Date, the
     Early Redemption Payment Date or otherwise;

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<PAGE>

          (b)  material default in the performance, or material breach, of any
     material covenant or warranty of the Company relating to the CVRs (other
     than a covenant or warranty in respect of the CVRs a default in whose
     performance or whose breach is elsewhere in this Section specifically dealt
     with), and continuance of such material default or breach for a period of
     90 days after there has been given, by registered or certified mail, to the
     Company by the Trustee or to the Company and the Trustee by the Holders of
     at least 25% of the Outstanding CVRs, a written notice specifying such
     material default or breach and requiring it to be remedied and stating that
     such notice is a "Notice of Default" hereunder;

          (c)  a court having jurisdiction in the premises shall enter a decree
     or order for relief in respect of the Company in an involuntary case under
     any applicable bankruptcy, insolvency or other similar law now or hereafter
     in effect, or appointing a receiver, liquidator, assignee, custodian,
     trustee or sequestrator (or similar official) of the Company or for any
     substantial part of its property or ordering the winding up or liquidation
     of its affairs, and such decree or order shall remain unstayed and in
     effect for a period of 60 consecutive days; or

          (d)  the Company shall commence a voluntary case under any applicable
     bankruptcy, insolvency or other similar law now or hereafter in effect, or
     consent to the entry of an order for relief in an involuntary case under
     any such law, or consent to the appointment of or taking possession by a
     receiver, liquidator, assignee, custodian, trustee or sequestrator (or
     similar official) of the Company or for any substantial part of its
     property, or make any general assignment for the benefit of creditors.

If an Event of Default described above occurs and is continuing, then, and in
each and every such case, unless all of the CVRs shall have already become due
and payable, either the Trustee or the Holders of not less than 25% of the CVRs
then Outstanding hereunder by notice in writing to the Company (and to the
Trustee if given by the Holders) may declare the CVRs to be due and payable
immediately, and upon any such declaration the Default Amount shall become
immediately due and payable and, thereafter, shall bear interest at the Default
Interest Rate until payment is made to the Trustee.

     The foregoing provisions, however, are subject to the condition that if, at
any time after the CVRs shall have been so declared due and payable, and before
any judgment or decree for the payment of the moneys due shall have been
obtained or entered as hereinafter provided, the Company shall pay or shall
deposit with the Trustee a sum sufficient to pay all amounts which shall have
become due otherwise than by acceleration (with interest upon such overdue
amount at the Default Interest Rate to the date of such payment or deposit) and
such amount as shall be sufficient to cover reasonable compensation to the
Trustee, its agents, attorneys and counsel, and all other expenses and
liabilities incurred and all advances made, by the Trustee except as a result of
negligence or bad faith, and if any and all Events of Default under this
Agreement, other than the nonpayment of the amounts which shall have become due
by acceleration, shall have

                                       39
<PAGE>

been cured, waived or otherwise remedied as provided herein, then and in every
such case the Holders of a majority of all the CVRs then Outstanding, by written
notice to the Company and to the Trustee, may waive all defaults with respect to
the CVRs and rescind and annul such declaration and its consequences, but no
such waiver or rescission and annulment shall extend to or shall affect any
subsequent default or shall impair any right consequent thereof.

Section 802.  Collection of Indebtedness by Trustee; Trustee May Prove Debt.

     The Company covenants that in case default shall be made in the payment of
all or any part of the CVRs when the same shall have become due and payable;
whether at the Maturity Date, the Early Redemption Payment Date, the Disposition
Payment Date, the Default Payment Date or otherwise, then upon demand of the
Trustee, the Company will pay to the Trustee for the benefit of the Holders of
the CVRs the whole amount, in Cash or Stock (in the Company's sole discretion),
that then shall have become due and payable on all CVRs (with interest from the
date due and payable to the date of such payment upon the overdue amount at the
Default Interest Rate); and, in addition thereto, such further amount as shall
be sufficient to cover the costs and expenses of collection, including
reasonable compensation to the Trustee and each predecessor Trustee, their
respective agents, attorneys and counsel, and any expenses and liabilities
incurred, and all advances made, by the Trustee and each predecessor Trustee
except as a result of its negligence or bad faith.

     In case the Company shall fail forthwith to pay such amounts upon such
demand, the Trustee, in its own name and as trustee of an express trust, shall
be entitled and empowered to institute any action or proceedings at law or in
equity for the collection of the sums so due and unpaid, and may prosecute any
such action or proceedings to judgment or final decree, and may enforce any such
judgment or final decree against the Company or other obligor upon such CVRs and
collect in the manner provided by law out of the property of the Company or
other obligor upon such CVRs, wherever situated, the moneys adjudged or decreed
to be payable.

     In case there shall be pending proceedings relative to the Company or any
other obligor upon the CVRs under Title 11 of the United States Code or any
other applicable Federal or State bankruptcy, insolvency or other similar law,
or in case a receiver, assignee or trustee in bankruptcy or reorganization,
liquidator, sequestrator or similar official shall have been appointed for or
taken possession of the Company or its property or such other obligor, or in
case of any other judicial proceedings relative to the Company or other obligor
upon the CVRs, or to the creditors or property of the Company or such other
obligor, the Trustee, irrespective of whether the principal of any CVRs shall
then be due and payable as therein expressed or otherwise and irrespective of
whether the Trustee shall have made any demand pursuant to the provisions of
this Section, shall be entitled and empowered, by intervention in such
proceedings or otherwise:

          (a)  to file and prove a claim or claims for the whole amount owing
     and unpaid in respect of the CVRs, and to file such other papers or
     documents as may

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<PAGE>

     be necessary or advisable in order to have the claims of the Trustee
     (including any claim for reasonable compensation to the Trustee and each
     predecessor Trustee, and their respective agents, attorneys and counsel,
     and for reimbursement of all expenses and liabilities incurred, and all
     advances made, by the Trustee and each predecessor Trustee, except as a
     result of negligence or bad faith) and of the Holders allowed in any
     judicial proceedings relative to the Company or other obligor upon the
     CVRs, or to the creditors or property of the Company or such other obligor;

          (b)  unless prohibited by applicable law and regulations, to vote on
     behalf of the Holders in any election of a trustee or a standby trustee in
     arrangement, reorganization, liquidation or other bankruptcy or insolvency
     proceedings or person performing similar functions in comparable
     proceedings; and

          (c)  to collect and receive any moneys or other property payable or
     deliverable on any such claims, and to distribute all amounts receivable
     with respect to the claims of the Holders and of the Trustee on their
     behalf and any trustee, receiver, or liquidator, custodian or other similar
     official is hereby authorized by each of the Holders to make payments to
     the Trustee, and, in the event that the Trustee shall consent to the making
     of payments directly to the Holders, to pay to the Trustee such amounts as
     shall be sufficient to cover reasonable compensation to the Trustee, each
     predecessor Trustee and their respective agents, attorneys and counsel, and
     all other expenses and liabilities incurred, and all advances made, by the
     Trustee and each predecessor Trustee except as a result of negligence or
     bad faith and all other amounts due to the Trustee or any predecessor
     Trustee pursuant to Section 406.

     Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or vote for or accept or adopt on behalf of any Holder
any plan of reorganization, arrangement, adjustment or composition affecting the
CVRs or the rights of any Holder thereof, or to authorize the Trustee to vote in
respect of the claim of any Holder in any such proceeding except, as aforesaid,
to vote for the election of a trustee in bankruptcy or similar person.

     All rights of action and of asserting claims under this Agreement, or under
any of the CVRs, may be enforced by the Trustee without the possession of any of
the CVRs or the production thereof at any trial or other proceedings relative
thereto, and any such action or proceedings instituted by the Trustee shall be
brought in its own name as trustee of an express trust, and any recovery of
judgment, subject to the payment of the expenses, disbursements and compensation
of the Trustee, each predecessor Trustee and their respective agents and
attorneys, shall be for the ratable benefit of the Holders.

     In any proceedings brought by the Trustee (and also any proceedings
involving the interpretation of any provision of this Agreement to which the
Trustee shall be a party) the Trustee shall be held to represent all the
Holders, and it shall not be necessary to make any Holders of such CVRs parties
to any such proceedings.

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<PAGE>

Section 803.  Application of Proceeds.

     Any monies (including CVRs or Shares) collected by the Trustee pursuant to
this Article in respect of any CVRs shall be applied in the following order at
the date or dates fixed by the Trustee upon presentation of the several CVRs in
respect of which monies (including CVRs or Shares) have been collected and
stamping (or otherwise noting) thereon the payment in exchange for the presented
CVRs if only partially paid or upon surrender thereof if fully paid:

          FIRST:  To the payment of costs and expenses in respect of which
     monies have been collected, including reasonable compensation to the
     Trustee and each predecessor Trustee and their respective agents and
     attorneys and of all expenses and liabilities incurred, and all advances
     made, by the Trustee and each predecessor Trustee except as a result of
     negligence or bad faith, and all other amounts due to the Trustee or any
     predecessor Trustee pursuant to Section 406;

          SECOND:  To the payment of the whole amount then owing and unpaid upon
     all the CVRs, with interest at the Default Interest Rate on all such
     amounts, and in case such moneys shall be insufficient to pay in full the
     whole amount so due and unpaid upon the CVRs, then to the payment of such
     amounts without preference or priority of any CVR over any other CVR,
     ratably to the aggregate of such amounts due and payable; and

          THIRD:  To the payment of the remainder, if any, to the Company or any
     other person lawfully entitled thereto.

Section 804.  Suits for Enforcement.

     In case an Event of Default has occurred, has not been waived and is
continuing, the Trustee may in its discretion proceed to protect and enforce the
rights vested in it by this Agreement by such appropriate judicial proceedings
as the Trustee shall deem most effectual to protect and enforce any of such
rights, either at law or in equity or in bankruptcy or otherwise, whether for
the specific enforcement of any covenant or agreement contained in this
Agreement or in aid of the exercise of any power granted in this Agreement or to
enforce any other legal or equitable right vested in the Trustee by this
Agreement or by law.

Section 805.  Restoration of Rights on Abandonment of Proceedings.

     In case the Trustee shall have proceeded to enforce any right under this
Agreement and such proceedings shall have been discontinued or abandoned for any
reason, or shall have been determined adversely to the Trustee, then and in
every such case the Company and the Trustee shall be restored respectively to
their former positions and rights hereunder, and all rights, remedies and powers
of the Company, the Trustee and the Holders shall continue as though no such
proceedings had been taken.

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<PAGE>

Section 806.  Limitations on Suits by Holders.

     No Holder of any CVR shall have any right by virtue or by availing itself
of any provision of this Agreement to institute any action or proceeding at law
or in equity or in bankruptcy or otherwise upon or under or with respect to this
Agreement, or for the appointment of a trustee, receiver, liquidator, custodian
or other similar official or for any other remedy hereunder, unless such Holder
previously shall have given to the Trustee written notice of default and of the
continuance thereof as hereinbefore provided, and unless also the Holders of not
less than 25% of the CVRs then Outstanding shall have made written request upon
the Trustee to institute such action or proceedings in its own name as trustee
hereunder and shall have offered to the Trustee such reasonable indemnity as it
may require against the costs, expenses and liabilities to be incurred therein
or thereby and the Trustee for 60 days after its receipt of such notice, request
and offer of indemnity shall have failed to institute any such action or
proceeding and no direction inconsistent with such written request shall have
been given to the Trustee pursuant to Section 809; it being understood and
intended, and being expressly covenanted by the taker and Holder of every CVR
with every other taker and Holder and the Trustee, that no one or more Holders
of CVRs shall have any right in any manner whatever by virtue or by availing
itself or themselves of any provision of this Agreement to effect, disturb or
prejudice the rights of any other such Holder of CVRs, or to obtain or seek to
obtain priority over or preference to any other such Holder or to enforce any
right under this Agreement, except in the manner herein provided and for the
equal, ratable and common benefit of all Holders of CVRs.  For the protection
and enforcement of the provisions of this Section, each and every Holder and the
Trustee shall be entitled to such relief as can be given either at law or in
equity.

Section 807.  Unconditional Right of Holders to Institute Certain Suits.

     Notwithstanding any other provision in this Agreement and any provision of
any CVR, the right of any Holder of any CVR to receive payment of the amounts
payable in respect of such CVR on or after the respective due dates expressed in
such CVR, or to institute suit for the enforcement of any such payment on or
after such respective dates, shall not be impaired or affected without the
consent of such Holder.

Section 808.  Powers and Remedies Cumulative; Delay or Omission Not Waiver of
            Default.

     Except as provided in Section 806, no right or remedy herein conferred upon
or reserved to the Trustee or to the Holders is intended to be exclusive of any
other right or remedy, and every right and remedy shall, to the extent permitted
by law, be cumulative and in addition to every other right and remedy given
hereunder or now or hereafter existing at law or in equity or otherwise.  The
assertion or employment of any right or remedy hereunder, or otherwise, shall
not prevent the concurrent assertion or employment of any other appropriate
right or remedy.

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<PAGE>

     No delay or omission of the Trustee or of any Holder to exercise any right
or power accruing upon any Event of Default occurring and continuing as
aforesaid shall impair any such right or power or shall be construed to be a
waiver of any such Event of Default or an acquiescence therein; and, subject to
Section 806, every power and remedy given by this Agreement or by law to the
Trustee or to the Holders may be exercised from time to time, and as often as
shall be deemed expedient, by the Trustee or by the Holders.

Section 809.  Control by Holders.

     The Holders of a majority of the CVRs at the time Outstanding shall have
the right to direct the time, method, and place of conducting any proceeding for
any remedy available to the Trustee, or exercising any trust or power conferred
on the Trustee with respect to the CVRs by this Agreement; provided that such
direction shall not be otherwise than in accordance with law and the provisions
of this Agreement; and provided further that (subject to the provisions of
Section 401) the Trustee shall have the right to decline to follow any such
direction if the Trustee, being advised by counsel, shall determine that the
action or proceeding so directed may not lawfully be taken or if the Trustee in
good faith by its board of directors, the executive committee, or a trust
committee of directors or Responsible Officers of the Trustee shall determine
that the action or proceedings so directed would involve the Trustee in personal
liability or if the Trustee in good faith shall so determine that the actions or
forbearances specified in or pursuant to such direction would be unduly
prejudicial to the interests of Holders of the CVRs not joining in the giving of
said direction, it being understood that (subject to Section 401) the Trustee
shall have no duty to ascertain whether or not such actions or forbearances are
unduly prejudicial to such Holders.

     Nothing in this Agreement shall impair the right of the Trustee in its
discretion to take any action deemed proper by the Trustee and which is not
inconsistent with such direction or directions by Holders.

Section 810.  Waiver of Past Defaults.

     Prior to the declaration of the acceleration of the maturity of the CVRs as
provided in Section 801, in the case of a default or an Event of Default
specified in clause (b), (c) or (d) of Section 801, the Holders of a majority of
all the CVRs then Outstanding may waive any such default or Event of Default,
and its consequences, except a default in respect of a covenant or provisions
hereof which cannot be modified or amended without the consent of the Holder of
each CVR affected.  In the case of any such waiver, the Company, the Trustee and
the Holders of the CVRs shall be restored to their former positions and rights
hereunder, respectively; but no such waiver shall extend to any subsequent or
other default or impair any right consequent thereon.

     Upon any such waiver, such default shall cease to exist and be deemed to
have been cured and not to have occurred, and any Event of Default arising
therefrom shall be deemed to have been cured, and not to have occurred for every
purpose of this

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<PAGE>

Agreement; but no such waiver shall extend to any subsequent or other default or
Event of Default or impair any right consequent thereon.

Section 811.  Trustee to Give Notice of Default, but May Withhold in Certain
              Circumstances.

     The Trustee shall transmit to the Holders, as the names and addresses of
such Holders appear on the Security Register, notice by mail of all defaults
which have occurred, such notice to be transmitted within 90 days after the
occurrence thereof unless such defaults shall have been cured before the giving
of such notice (the term "default" or "defaults" for the purposes of this
Section being hereby defined to mean any event or condition which is, or with
notice or lapse of time or both would become, an Event of Default); provided
that, except in the case of default in the payment of the amounts payable in
respect of any of the CVRs, the Trustee shall be protected in withholding such
notice if and so long as the board of directors, the executive committee, or a
trust committee of directors or trustees and/or Responsible Officers of the
Trustee in good faith determines that the withholding of such notice is in the
interests of the Holders.

Section 812.  Right of Court to Require Filing of Undertaking to Pay Costs.

     All parties to this Agreement agree, and each Holder of any CVR by his
acceptance thereof shall be deemed to have agreed, that any court may in its
discretion require, in any suit for the enforcement of any right or remedy under
this Agreement or in any suit against the Trustee for any action taken, suffered
or omitted by it as Trustee, the filing by any party litigant in such suit of an
undertaking to pay the costs of such suit, and that such court may in its
discretion assess reasonable costs, including reasonable attorneys' fees,
against any party litigant in such suit, having due regard to the merits and
good faith or the claims or defenses made by such party litigant; but the
provisions of this Section shall not apply to any suit instituted by the
Trustee, to any suit instituted by any Holder or group of Holders holding in the
aggregate more than 10% of the CVRs Outstanding or to any suit instituted by any
Holder for the enforcement of the payment of any CVR on or after the due date
expressed in such CVR.

                                  ARTICLE NINE

                   CONSOLIDATION, MERGER, SALE OR CONVEYANCE

Section 901.  Company May Consolidate, Etc.

     The Company shall not consolidate with or merge into any other Person or
convey, transfer or lease its properties and assets substantially as an entirety
to any Person, unless:

          (1)  in case the Company shall consolidate with or merge into any
     other Person or convey, transfer or lease its properties and assets
     substantially as an

                                       45
<PAGE>

     entirety to any Person, the Person formed by such consolidation or into
     which the Company is merged or the Person which acquires by conveyance or
     transfer, or which leases, the properties and assets of the Company
     substantially as an entirety (the "Surviving Person") shall be a
     corporation, partnership or trust organized and existing under the laws of
     the United States of America, any state thereof or the District of
     Columbia, the United Kingdom, Bermuda, the Republic of Ireland, Barbados,
     the Channel Islands, the Cayman Islands or any other jurisdiction that is
     not materially adverse to the Holders and shall expressly assume payment of
     amounts on all the CVRs and the performance of every covenant of this
     Agreement on the part of the Company to be performed or observed;

          (2) immediately after giving effect to such transaction, no Event of
     Default shall have happened and be continuing; and

          (3)  the Company has delivered to the Trustee an Officer's Certificate
     stating that such consolidation, merger, conveyance, transfer or lease
     complies with this Article and that all conditions precedent herein
     provided for relating to such transaction have been complied with.

     Solely for purposes of this Section 901, "convey, transfer or lease its
properties and assets substantially as an entirety" shall mean properties and
assets contributing in the aggregate at least 80% of the Company's total
revenues as reported in the Company's last available periodic financial report
(quarterly or annual, as the case may be) filed with the Commission.

Section 902.  Successor Substituted.

     Upon any consolidation of or merger by the Company with or into any other
Person, or any conveyance, transfer or lease of the properties and assets
substantially as an entirety to any Person in accordance with Section 901, the
Surviving Person shall succeed to, and be substituted for, and may exercise
every right and power of, the Company under this Agreement with the same effect
as if the Surviving Person had been named as the Company herein, and thereafter,
the predecessor corporation shall be relieved of all obligations and covenants
under this Agreement and the CVRs.

Section 903.  Opinion of Counsel to Trustee.

     The Trustee, subject to the provisions of Sections 401 and 402, may receive
an Opinion of Counsel, prepared in accordance with Sections 103 and 104, as
conclusive evidence that any such consolidation, merger, sale, lease or
conveyance, and any such assumption, and any such liquidation or dissolution,
complies with the applicable provisions of this Agreement.

                                       46
<PAGE>

                                 * * * * * * *

     This Agreement may be signed in any number of counterparts with the same
effect as if the signatures to each counterpart were upon a single instrument,
and all such counterparts together shall be deemed an original of this
Agreement.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed, and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

                              MARKEL HOLDINGS INC.

                              By:_________________________________
                                    Title:

Attest:

__________________________
Title:

                              [TRUSTEE]

                              By:_________________________________
                                    Title:

Attest:

____________________________
Title:

                                       47
<PAGE>

State of    )
  )    ss.:
County of     )

     On the            day of February ____, 2000, before me personally came
, to me known, who, being by me duly sworn, did depose and say that s/he resides
at      ; that s/he is                                   of Markel Holdings
Inc., one of the corporations described in and which executed the above
instrument; and s/he knows the corporate seal of such corporation; that the seal
affixed to said instrument is such corporate seal; that it was so affixed
pursuant to authority of the Board of Directors of such corporation; and that
s/he signed her/his name thereto pursuant to like authority.

                              (NOTARIAL SEAL)

                              ___________________________________

State of  )
     )    ss.:
County of )

     On the                 day of February ____, 2000, before me personally
came             , to me known, who, being by me duly sworn, did depose and say
that s/he resides at         ; that s/he is
of [TRUSTEE], one of the corporations described in and which executed the above
instrument; and s/he knows the corporate seal of such corporation; that the seal
affixed to said instrument is such corporate seal; that it was so affixed
pursuant to authority of the Board of Directors of such corporation; and that
s/he signed her/his name thereto pursuant to like authority.

                              (NOTARIAL SEAL)

                              ____________________________________

                                       48<PAGE>   1

                            MCK COMMUNICATIONS, INC.
                        1999 STOCK OPTION AND GRANT PLAN

         SECTION 1. GENERAL PURPOSE OF THE PLAN; DEFINITIONS

         The name of the plan is the MCK Communications, Inc. 1999 Stock Option
and Grant Plan (the "Plan"). The purpose of the Plan is to encourage and enable
the officers, employees, directors, consultants, advisors and other key persons
of MCK Communications, Inc. (the "Company") and its Subsidiaries (as defined
below) upon whose judgment, initiative and efforts the Company largely depends
for the successful conduct of its business to acquire a proprietary interest in
the Company. It is anticipated that providing such persons with a direct stake
in the Company's welfare will assure a closer identification of their interests
with those of the Company, thereby stimulating their efforts on the Company's
behalf and strengthening their desire to remain with the Company.

         The following terms shall be defined as set forth below:

         "Act" means the Securities Exchange Act of 1934, as amended.

         "Award" or "Awards," except where referring to a particular category of
grant under the Plan, shall include Incentive Stock Options, Non-Qualified Stock
Options, Restricted Stock Awards, and Unrestricted Stock Awards.

         "Board" means the Board of Directors of the Company.

         "Code" means the Internal Revenue Code of 1986, as amended, and any
successor Code, and related rules, regulations and interpretations.

         "Committee" has the meaning specified in Section 2.

         "Effective Date" means the date on which the Plan is approved by
stockholders as set forth in Section 13.

         "Fair Market Value" of the Stock on any given date means (i) if the
Stock is admitted to quotation on the National Association of Securities Dealers
Automated Quotation System ("NASDAQ"), the Fair Market Value on any given date
shall not be less than the average of the highest bid and lowest asked prices of
the Stock reported for such date or, if no bid and asked prices were reported
for such date, for the last day preceding such date for which such prices were
reported; or (ii) if the Stock is admitted to trading on a national securities
exchange or the NASDAQ National Market System, then clause (i) shall not apply
and the Fair Market Value on any date shall not be less than the closing price
reported for the Stock on such exchange or system for such date or, if no sales
were reported for such date, for the last date preceding such date for which a
sale was reported; or (iii) if the Stock is not publicly traded on a securities
exchange or traded in the over-the-counter market or, if traded or quoted, there
are no transactions or quotations within the last ten trading days or trading
has been halted for

<PAGE>   2

extraordinary reasons, the Fair Market Value on any given date shall be
determined in good faith by the Committee with reference to the rules and
principles of valuation set forth in Section 20.2031-2 of the Treasury
Regulations; and (iv) notwithstanding the foregoing, the Fair Market Value of
the Stock on the effective date of the Initial Public Offering shall be the
offering price to the public of the Stock on such date.

         "Incentive Stock Option" means any Stock Option designated and
qualified as an "incentive stock option" as defined in Section 422 of the Code.

         "Independent Director" means a member of the Board who is neither an
employee or officer of the Company or any Subsidiary.

         "Initial Public Offering" means the first underwritten public offering
pursuant to an effective registration statement under the Securities Act of
1933, as amended, covering the offer and sale of Stock to the public.

         "Non-Qualified Stock Option" means any Stock Option that is not an
Incentive Stock Option.

         "Option" or "Stock Option" means any option to purchase shares of Stock
granted pursuant to Section 5.

         "Restricted Stock Award" means any Award granted pursuant to Section 6.

         "Stock" means the Common Stock, par value $.001 per share, of the
Company, subject to adjustments pursuant to Section 3.

         "Subsidiary" means any corporation or other entity (other than the
Company) in any unbroken chain of corporations or other entities, beginning with
the Company, if each of the corporations or entities (other than the last
corporation or entity in the unbroken chain) owns stock or other interests
possessing 50% or more of the economic interest or the total combined voting
power of all classes of stock or other interests in one of the other
corporations or entities in the chain.

         "Unrestricted Stock Award" means any Award granted pursuant to Section
7.

         SECTION 2. ADMINISTRATION OF PLAN; COMMITTEE AUTHORITY TO SELECT
PARTICIPANTS AND DETERMINE AWARDS.

         (a) COMMITTEE. The Plan shall be administered by the Board of Directors
of the Company, or at the discretion of the Board, by a committee of the Board
consisting of not less than two Directors; PROVIDED, HOWEVER, that if each
member of the Committee is not (i) a "Non-Employee Director" within the meaning
of Rule 16b-3(a)(3) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act") and (ii) an "Outside Director" within the meaning of Section
162(m) of the Code and the regulations promulgated thereunder, any Awards
granted to individuals subject to the reporting requirements of Section 16 of
the Exchange Act

                                      -2-

<PAGE>   3

shall be approved by the Board of Directors. All references herein to the
Committee shall be deemed to refer to the entity then responsible for
administration of the Plan at the relevant time (i.e., either the Board of
Directors or a committee of the Board, as applicable).

         (b) POWERS OF COMMITTEE. The Committee shall have the power and
authority to grant Awards consistent with the terms of the Plan, including the
power and authority:

                  (1) to select the officers, employees, Independent Directors,
consultants, advisers and key persons of the Company and its Subsidiaries to
whom Awards may from time to time be granted;

                  (2) to determine the time or times of grant, and the extent,
if any, of Incentive Stock Options, Non-Qualified Stock Options, Restricted
Stock Awards and Unrestricted Stock Awards, or any combination of the foregoing,
granted to any one or more participants;

                  (3) to determine the number of shares of Stock to be covered
by any Award;

                  (4) to determine and modify from time to time the terms and
conditions, including restrictions, not inconsistent with the terms of the Plan,
of any Award, which terms and conditions may differ among individual Awards and
participants, and to approve the form of written instruments evidencing the
Awards;

                  (5) to accelerate at any time the exercisability or vesting of
all or any portion of any Award and/or to include provisions in Awards providing
for such acceleration,

                  (6) to impose any limitations on Awards granted under the
Plan, including limitations on transfers repurchase provisions and the like and
to exercise repurchase rights or obligations;

                  (7) subject to the provisions of Section 5(a)(3), to extend at
any time the period in which Stock Options may be exercised;

                  (8) to determine at any time whether, to what extent, and
under what circumstances Stock and other amounts payable with respect to an
Award shall be deferred either automatically or at the election of the
participant and whether and to what extent the Company shall pay or credit
amounts constituting interest (at rates determined by the Committee) or
dividends or deemed dividends on such deferrals; and

                  (9) at any time to adopt, alter and repeal such rules,
guidelines and practices for administration of the Plan and for its own acts and
proceedings as it shall deem advisable, to interpret the terms and provisions of
the Plan and any Award (including related written instruments); to make all
determinations it deems advisable for the administration of the Plan; to decide
all disputes arising in connection with the Plan; and to otherwise supervise the
administration of the plan.

                                      -3-

<PAGE>   4

                  All decisions and interpretations of the Committee shall be
binding on all persons, including the Company and Plan participants.

                  (c) DELEGATION OF AUTHORITY TO GRANT AWARDS. The Committee, in
its discretion, may delegate to the Chief Executive Officer of the Company all
or part of the Committee's authority and duties with respect to Awards,
including the granting thereof, to individuals who are not subject to the
reporting and other provisions of Section 16 of the Act or "covered employees"
within the meaning of Section 162(m) of the Code. Any such delegation by the
Committee shall include a limitation as to the amount of Awards that may be
granted during the period of delegation and shall contain guidelines as to the
determination of the exercise price of any Option, the price of other Awards and
the vesting criteria. The Committee may revoke or amend the terms of a
delegation at any time but such action shall not invalidate any prior actions of
the Committee's delegate or delegates that were consistent with the terms of the
Plan.

         SECTION 3. STOCK ISSUABLE UNDER THE PLAN; MERGERS; SUBSTITUTION

                  (a) STOCK ISSUABLE. The maximum number of shares of Stock
reserved and available for issuance under the Plan shall be 2,000,000 shares of
Stock. For purposes of the foregoing limitations, the shares of Stock underlying
any Awards which are forfeited, canceled, reacquired by the Company, satisfied
without the issuance of Stock or otherwise terminated (other than by exercise)
shall be added back to the shares of Stock available for issuance under the
Plan. Subject to such overall limitation, shares of Stock may be issued up to
such maximum number pursuant to any type or types of Award; PROVIDED, HOWEVER,
that from and after the date the plan is subject to Section 162(m) of the Code,
Awards with respect to no more than 500,000 shares of Stock may be granted to
any one individual participant during any one calendar year period. The shares
available for issuance under the Plan may be authorized but unissued shares of
Stock or shares of Stock reacquired by the Company.

                  (b) RECAPITALIZATIONS. If, through or as a result of any
merger, consolidation, sale of all or substantially all of the assets of the
Company, reorganization, recapitalization, reclassification, stock dividend,
stock split, reverse stock split or other similar transaction, the outstanding
shares of Stock are increased or decreased or are exchanged for a different
number or kind of shares or other securities of the Company or any successor
company, or additional shares or new or different shares or other securities of
the Company or other non-cash assets are distributed with respect to such shares
of Stock or other securities, the Committee shall make an appropriate or
proportionate adjustment in (i) the maximum number of shares reserved for
issuance under the Plan, (ii) the number of Stock Options, or other Awards that
can be granted to any one individual participant, (iii) the number and kind of
shares or other securities subject to any then outstanding Awards under the
Plan, and (iv) the price for each share subject to any then outstanding Stock
Options or other Awards under the Plan, without changing the aggregate exercise
price (i.e., the exercise price multiplied by the number of shares) as to which
such Stock Options remain exercisable and the repurchase price for shares
subject to repurchase. The adjustment by the Committee shall be final, binding
and conclusive. No fractional shares of

                                      -4-

<PAGE>   5

Stock shall be issued under the Plan resulting from any such adjustment, but the
Committee in its discretion may make cash payment in lieu of fractional shares.

                  (c) MERGERS AND OTHER TRANSACTIONS. In the case of (i) the
dissolution or liquidation of the Company, (ii) a merger, reorganization or
consolidation between the Company and another person or entity (other than a
holding company or subsidiary of the Company) as a result of which the holders
of the Company's outstanding voting stock immediately prior to the transaction
hold less than a majority of the outstanding voting stock of the surviving
entity immediately after the transaction, (iii) the sale of all or substantially
all of the assets of the Company to an unrelated person or entity, or (iv) the
sale of all of the Stock of the Company to an unrelated person or entity (in
each case, a "Transaction"), fifty percent (50%) of the outstanding Awards held
by participants, to the extent not fully vested and exercisable, shall become
fully vested and exercisable, except with respect to specific awards as the
Committee otherwise determines at the time of grant of such awards. In addition,
unless provision is made in connection with the Transaction for the assumption
of the Awards heretofore granted, or the substitution of such Awards with new
Awards of the successor entity or parent thereof, with appropriate adjustment as
to the number and kind of shares and, if appropriate, the per share exercise
prices, as provided in Section 3(b) above, all of the remaining outstanding
Awards held by participants, to the extent not fully vested and exercisable,
shall become fully vested and exercisable, except with respect to specific
awards as the Committee otherwise determines. Upon the effectiveness of the
transaction, the Plan and all Awards ("Contractual Awards") granted hereunder
shall, unless assumed by the successor entity, terminate. In the event of such
termination, each optionee shall be permitted to exercise for a period of at
least 15 days prior to the date of such termination all outstanding Awards held
by such optionee which are then exercisable.

                  (d) SUBSTITUTE AWARDS. The Committee may grant Awards under
the Plan in substitution for stock and stock based awards held by employees of
another corporation who become employees of the Company or a Subsidiary as the
result of a merger or consolidation of the employing corporation with the
Company or a Subsidiary or the acquisition by the Company or a Subsidiary of
property or stock of the employing corporation. The Committee may direct that
the substitute awards be granted on such terms and conditions as the Committee
considers appropriate in the circumstances.

         SECTION 4. ELIGIBILITY.

                  Participants in the Plan will be such officers and other
employees, Independent Directors, consultants, advisors and other key persons of
the Company and its Subsidiaries who are responsible for or contribute to the
management, growth or profitability of the Company and its Subsidiaries as are
selected from time to time by the Committee, in its sole discretion.

         SECTION 5. STOCK OPTIONS.

                  Any Stock Option granted under the Plan shall be pursuant to a
stock option agreement which shall be in such form as the Committee may from
time to time approve. Option agreements need not be identical.

                                      -5-

<PAGE>   6

                  Stock Options granted under the Plan may be either Incentive
Stock Options or Non-Qualified Stock Options. Incentive Stock Options may be
granted only to employees of the Company or any Subsidiary that is a "subsidiary
corporation" within the meaning of Section 424(f) of the Code. Non-Qualified
Stock Options may be granted to officers, employees, Independent Directors,
advisors, consultants and other key persons of the Company and its Subsidiaries.
To the extent that any Option does not qualify as an Incentive Stock Option, it
shall be deemed a Non-Qualified Stock option.

                  No Incentive Stock Option shall be granted under the Plan
after August 19, 2009.

                  (a) TERMS OF STOCK OPTIONS. Stock Options granted under the
plan shall be subject to the following terms and conditions and shall contain
such additional terms and conditions, not inconsistent with the terms of the
Plan as the Committee shall deem desirable:

                           (1) EXERCISE PRICE. The exercise price per share for
the Stock covered by a Stock Option shall be determined by the Committee at the
time of grant but shall not be less than 100% of the Fair Market Value in the
case of Incentive Stock Options. If an employee owns or is deemed to own (by
reason of the attribution rules applicable under Section 424(d) of the Code)
more than 10% of the combined voting power of all classes of stock of the
Company or any parent or subsidiary corporation and an Incentive Stock Option is
granted to such employee, the option price of such Incentive Stock Option shall
be not less than 110% of the Fair Market Value on the grant date.

                           (2) GRANT OF DISCOUNT OPTIONS IN LIEU OF CASH
COMPENSATION. Upon the request of a participant and with the consent of the
Committee, such participant may elect each calendar year to receive a
Non-Qualified Stock Option in lieu of any cash bonus or other compensation to
which he may become entitled during the following calendar year, but only if
such participant makes an irrevocable election to waive receipt of all or a
portion of such cash compensation. Such election shall be made on or before the
date set by the Committee which date shall be no later than 15 days (or such
shorter period permitted by the Committee) preceding January 1 of the calendar
year for which the cash compensation would otherwise be paid. A Non-Qualified
Stock Option shall be granted to each participant who made such an irrevocable
election on the date the waived cash compensation would otherwise be paid. The
exercise price per share shall be determined by the Committee. The number of
shares of Stock subject to the stock Option shall be determined by dividing the
amount of the waived cash compensation by the difference between the Fair Market
Value of the Stock on the date the Stock Option is granted and the exercise
price per share of the Stock Option. The Stock Option shall be granted for a
whole number of shares so determined; the value of any fractional share shall be
paid in cash.

                           (3) OPTION TERM. The term of each Stock Option shall
be fixed by the Committee, but no Incentive Stock Option shall be exercisable
more than ten years after the date the Option is granted. If an employee owns or
is deemed to own (by reason of the attribution rules of Section 424(d) of the
Code) more than 10% of the combined voting power of all classes of Stock of the
Company or any parent or subsidiary corporation and an Incentive Stock Option

                                      -6-

<PAGE>   7

is granted to such employee, the term of such Option shall be no more than five
years from the date of grant.

                           (4) EXERCISABILITY; RIGHTS OF A STOCKHOLDER. Stock
Options shall become vested and exercisable at such time or times, whether or
not in installments, as shall be determined by the Committee at or after the
grant date; PROVIDED, HOWEVER, that Stock Options granted in lieu of cash
compensation shall be exercisable in full as of the grant date. The Committee
may at any time accelerate the exercisability of all or any portion of any Stock
Option. An optionee shall have the rights of a stockholder only as to shares
acquired upon the exercise of a Stock Option and not as to unexercised Stock
Options.

                           (5) METHOD OF EXERCISE. Stock Options may be
exercised in whole or in part, by giving written notice of exercise to the
Company, specifying the number of shares to be purchased. Payment of the
purchase price may be made by one or more of the following methods; provided,
however, that the methods set forth in subsections (B) and (C) below shall
become available only after the closing of the Initial Public Offering:

                                    (i) In cash by certified or bank check or
other instrument acceptable to the Committee,

                                    (ii) In the form of shares of Stock that are
not then subject to restrictions under any Company plan and that have been held
by the optionee free of such restrictions for at least six months, if permitted
by the Committee in its discretion. such surrendered shares shall be valued at
Fair Market Value on the exercise date;

                                    (iii) By the optionee delivering to the
Company a properly executed exercise notice together with irrevocable
instructions to a broker to promptly deliver to the Company cash or a check
payable and acceptable to the Company to pay the purchase price; provided that
in the event the optionee chooses to pay the purchase price as so provided, the
optionee and the broker shall comply with such procedures and enter into such
agreements of indemnity and other agreements as the Committee shall prescribe as
a condition of such payment procedure; or

                                    (iv) By the optionee delivering to the
Company a promissory note if the Board has authorized the loan of funds to the
optionee for the purpose of enabling or assisting the optionee to effect the
exercise of his Stock Option; PROVIDED THAT at least so much of the exercise
price as represents the par value of the Stock shall be paid other than with a
promissory note.

                  Payment instruments will be received subject to collection.
The delivery of certificates representing the shares of Stock to be purchased
pursuant to the exercise of a Stock Option will be contingent upon receipt from
the optionee (or a purchaser acting in his stead in accordance with the
provisions of the Stock Option) by the Company of the full purchase price for
such shares and the fulfillment of any other requirements contained in the Stock
Option or applicable provisions of laws.

                                      -7-

<PAGE>   8

                           (6) TERMINATION. Unless otherwise provided in the
option agreement or determined by the Committee, upon the optionee's termination
of employment (or other business relationship) with the Company and its
Subsidiaries, the optionee's rights in his Stock Options shall automatically
terminate.

                           (7) ANNUAL LIMIT ON INCENTIVE STOCK OPTIONS. To the
extent required for "incentive stock option" treatment under Section 422 of the
Code, the aggregate Fair Market Value (determined as of the time of grant) of
the shares of Stock with respect to which Incentive Stock Options granted under
this Plan and any other plan of the Company or its parent and subsidiary
corporations become exercisable for the first time by an optionee during any
calendar year shall not exceed $100,000. To the extent that any Stock Option
exceeds this limit, it shall constitute a Non-Qualified Stock Option.

                  (b) RELOAD OPTIONS. At the discretion of the Committee,
Options granted under the Plan may include a "reload" feature pursuant to which
an optionee exercising an Option by the delivery of number of shares of stock in
accordance with Section 5(a)(5)(ii) hereof would automatically be granted an
additional Option (with an exercise price equal to the Fair Market Value of the
Stock on the date the additional Option is granted and with the same expiration
date as the original Option being exercised, and with such other terms as the
Committee may provide) to purchase that number of shares of Stock equal to the
number delivered to exercise the original Option.

                  (c) NON-TRANSFERABILITY OF OPTIONS. No Stock option shall be
transferable by the optionee otherwise than by will or by the laws of descent
and distribution and all Stock Options shall be exercisable, during the
optionee's lifetime, only by the optionee; provided, however, that an optionee
may transfer, without consideration for the transfer, the Non-Qualified Stock
Options to members of his immediate family, to trusts for the benefit of such
family members, to partnerships in which such family members are the only
partners, or to charitable organization so long as the transferee agrees in
writing to be bound by the terms and conditions of this Plan and the applicable
Option Agreement.

         SECTION 6. RESTRICTED STOCK AWARDS

                  (a) NATURE OF RESTRICTED STOCK AWARDS. A Restricted Stock
Award is an Award entitling the recipient to acquire, at par value or such other
purchase price determined by the Committee, shares of Stock subject to such
restrictions and conditions as the Committee may determine at the time of grant
("Restricted Stock"). Conditions may be based on continuing employment (or other
business relationship) and/or achievement or pre-established performance goals
and objectives.

                  (b) RIGHTS AS A STOCKHOLDER. Upon execution of a written
instrument setting forth the Restricted Stock Award and paying any applicable
purchase price, a participant shall have the rights of a stockholder with
respect to the voting of the Restricted Stock, subject to such conditions
contained in the written instrument evidencing the Restricted Stock Award.
Unless the Committee shall otherwise determine, certificates evidencing the
Restricted Stock shall

                                      -8-

<PAGE>   9

remain in the possession of the Company until such Restricted Stock is vested as
provided in Section 6(d) below.

                  (c) RESTRICTIONS. Restricted Stock may not be sold, assigned,
transferred, pledged or otherwise encumbered or disposed of except as
specifically provided herein or in the written instrument evidencing the
Restricted Stock Award. If a participant's employment (or other business
relationship) with the Company and its Subsidiaries terminates under the
conditions specified in the relevant instrument relating to the Award, or upon
such other event or events as may be stated in the instrument evidencing the
Award, the Company or its assigns shall have the right or shall agree, as may be
specified in the relevant instrument, to repurchase some or all of the shares of
Stock subject to the Award at such purchase price as is set forth in such
instrument.

                  (d) VESTING OF RESTRICTED STOCK. The Committee at the time of
grant shall specify the date or dates and/or the attainment of pre-established
performance goals, objectives and other conditions on which Restricted Stock
shall become vested, subject to such further rights of the Company or its
assigns as may be specified in the instrument evidencing the Restricted Stock
Award.

                  (e) WAIVER, DEFERRAL AND REINVESTMENT OF DIVIDENDS. The
written instrument evidencing the Restricted Stock Award may require or permit
the immediate payment, waiver, deferral or investment of dividends paid on the
Restricted Stock.

         SECTION 7. UNRESTRICTED STOCK AWARDS

                  (a) GRANT OR SALE OF UNRESTRICTED STOCK. The Committee may, in
its sole discretion, grant (or sell at a purchase price determined by the
Committee) an Unrestricted Stock Award to any participant, pursuant to which
such participant may receive shares of Stock free of any vesting restrictions
("Unrestricted Stock") under the Plan. Unrestricted Stock Awards may be granted
or sold as described in the preceding sentence in respect of past services or
other valid consideration, or in lieu of any cash compensation due to such
individual.

                  (b) ELECTIONS TO RECEIVE UNRESTRICTED STOCK IN LIEU OF
COMPENSATION. Upon the request of a participant and with the consent of the
Committee, each such participant may, pursuant to an advance written election
delivered to the Company no later than the date specified by the Committee,
receive a portion of the cash compensation otherwise due to such participant in
the form of shares of Unrestricted Stock either currently or on a deferred
basis.

                  (c) RESTRICTIONS ON TRANSFERS. The right to receive shares of
Unrestricted Stock on a deferred basis may not be sold, assigned, transferred,
pledged or otherwise encumbered, other than by will or the laws of descent and
distribution.

         SECTION 8. TAX WITHHOLDING

                  (a) PAYMENT BY PARTICIPANT. Each participant shall, no later
than the date as of which the value of an Award or of any Stock or other amounts
received thereunder first becomes includable in the gross income of the
participant for Federal income tax purposes, pay to the

                                      -9-

<PAGE>   10

Company, or make arrangements satisfactory to the Committee regarding payment
of, any federal, state, or local taxes of any kind required by law to be
withheld with respect to such income. The Company and its Subsidiaries shall, to
the extent permitted by law, have the right to deduct any such taxes from any
payment of any kind otherwise due to the participant.

                  (b) PAYMENT IN STOCK. Subject to approval by the Committee, a
participant may elect to have such tax withholding obligation satisfied, in
whole or in part, by (i) authorizing the Company to withhold from shares of
Stock to be issued pursuant to any Award a number of shares with an aggregate
Fair Market Value (as of the date the withholding is effected) that would
satisfy the withholding amount due, or (ii) transferring to the Company shares
of Stock owned by the participant with an aggregate Fair Market Value (as of the
date the withholding is effected) that would satisfy the withholding amount due.

         SECTION 9. TRANSFER, LEAVE OF ABSENCE, ETC.

                  For purposes of the Plan, the following events shall not be
deemed a termination of employment:

                  (a) a transfer to the employment of the Company from a
subsidiary or from the Company to a Subsidiary, or from one Subsidiary to
another; or

                  (b) an approved leave of absence for military service or
sickness, or for any other purpose approved by the Company, if the employee's
right to re-employment is guaranteed either by a statute or by contract or under
the policy pursuant to which the leave of absence was granted or if the
Committee otherwise so provides in writing.

         SECTION 10. AMENDMENTS AND TERMINATION

         The Board may, at any time, amend or discontinue the Plan and the
Committee may, at any time, amend or cancel any outstanding Award (or provide
substitute Awards at the same or reduced exercise or purchase price or with no
exercise or purchase price in a manner not inconsistent with the terms of the
Plan), but such price, if any, must satisfy the requirements which would apply
to the substitute or amended Award if it were then initially granted under this
Plan for the purpose of satisfying changes in law or for any other lawful
purpose, but no such action shall adversely affect rights under any outstanding
Award without the holder's consent. If and to the extent determined by the
Committee to be required by the Act to ensure that Incentive Stock Options
granted under the Plan are qualified under Section 422 of the Code, Plan
amendments shall be subject to approval by the Company's stockholders who are
eligible to vote at a meeting of stockholders.

         SECTION 11. STATUS OF PLAN

         With respect to the portion of any Award which has not been exercised
and any payments in cash, Stock or other consideration not received by a
participant, a participant shall have no rights greater than those of a general
creditor of the company unless the Committee shall otherwise expressly determine
in connection with any Award or Awards. In its sole discretion, the Committee
may authorize the creation of trusts or other arrangements to meet the Company's

                                      -10-

<PAGE>   11

obligations to deliver Stock or make payments with respect to Awards hereunder,
PROVIDED THAT the existence of such trusts or other arrangements is consistent
with the foregoing sentence.

         SECTION 12. GENERAL PROVISIONS

                  (a) NO DISTRIBUTION; COMPLIANCE WITH LEGAL REQUIREMENTS. The
Committee may require each person acquiring Stock pursuant to an Award to
represent to and agree with the Company in writing that such person is acquiring
the shares without a view to distribution thereof.

                  No shares of Stock shall be issued pursuant to an Award until
all applicable securities law and other legal and stock exchange or similar
requirements have been satisfied. The Committee may require the placing of such
stop orders and restrictive legends on certificates for Stock and Awards, as it
deems appropriate.

                  (b) OTHER COMPENSATION ARRANGEMENTS; NO EMPLOYMENT RIGHTS.
Nothing contained in this Plan shall prevent the Board from adopting other or
additional compensation arrangements, including trusts, and such arrangements
may be either generally applicable or applicable only in specific cases. The
adopting of this Plan and the grant of Awards do not confer upon any employee
any right to continued employment with the Company or any Subsidiary.

         SECTION 13. EFFECTIVE DATE OF PLAN

         This Plan shall become effective upon approval by the holders of a
majority of the shares of Stock of the Company present or represented and
entitled to vote at a meeting of stockholders. Subject to such approval by the
stockholders and to the requirement that no Stock may be issued hereunder prior
to such approval, Stock Options and other Awards may be granted hereunder on and
after adoption of this Plan by the Board.

         SECTION 14. GOVERNING LAW

         This Plan shall be governed by Delaware law except to the extent such
law is preempted by federal law.

Adopted and Effective: August 20, 1999

                                      -11-

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