<PAGE>
                                                                     Exhibit 4.3

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                      AMENDED AND RESTATED TRUST AGREEMENT

                         W. R. BERKLEY CAPITAL TRUST II

                            Dated as of July 26, 2005

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<PAGE>


                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                                         PAGE
                                                                                                         ----
<S>                                                                                                      <C>
ARTICLE I INTERPRETATION AND DEFINITIONS

   SECTION 1.1.    Definitions.......................................................................      1

ARTICLE II TRUST INDENTURE ACT

   SECTION 2.1.    Trust Indenture Act; Application..................................................      7
   SECTION 2.2.    Lists of Holders of Securities....................................................      7
   SECTION 2.3.    Reports by the Property Trustee...................................................      8
   SECTION 2.4.    Periodic Reports to Property Trustee..............................................      8
   SECTION 2.5.    Evidence of Compliance with Conditions Precedent..................................      8
   SECTION 2.6.    Events of Default; Waiver.........................................................      8
   SECTION 2.7.    Event of Default; Notice..........................................................     10

ARTICLE III ORGANIZATION

   SECTION 3.1.    Name..............................................................................     10
   SECTION 3.2.    Office............................................................................     10
   SECTION 3.3.    Purpose...........................................................................     11
   SECTION 3.4.    Authority.........................................................................     11
   SECTION 3.5.    Title to Property of the Trust....................................................     11
   SECTION 3.6.    Powers and Duties of the Administrative Trustees..................................     11
   SECTION 3.7.    Prohibition of Actions by the Trust and the Trustees..............................     14
   SECTION 3.8.    Powers and Duties of the Property Trustee.........................................     15
   SECTION 3.9.    Certain Duties and Responsibilities of the Property Trustee.......................     16
   SECTION 3.10.   Certain Rights of Property Trustee................................................     18
   SECTION 3.11.   Delaware Trustee..................................................................     21
   SECTION 3.12.   Execution of Documents............................................................     21
   SECTION 3.13.   Not Responsible for Recitals or Issuance of Securities............................     21
   SECTION 3.14.   Duration of Trust.................................................................     21
   SECTION 3.15.   Mergers...........................................................................     21

ARTICLE IV SPONSOR

   SECTION 4.1.    Sponsor's Purchase of Common Securities...........................................     23
   SECTION 4.2.    Responsibilities of the Sponsor...................................................     23

ARTICLE V TRUSTEES

   SECTION 5.1.    Number of Trustees................................................................     24
   SECTION 5.2.    Delaware Trustee..................................................................     25
   SECTION 5.3.    Property Trustee; Eligibility.....................................................     25
   SECTION 5.4.    Certain Qualifications of Administrative Trustees and Delaware Trustee Generally..     26
   SECTION 5.5.    Administrative Trustees...........................................................     26
   SECTION 5.6.    Appointment, Removal and Resignation of Trustees..................................     26
   SECTION 5.7.    Vacancies Among Trustees..........................................................     28
   SECTION 5.8.    Effect of Vacancies...............................................................     28
</TABLE>

                                       i
<PAGE>

                                TABLE OF CONTENTS
                                  (continued)

<TABLE>
<CAPTION>
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<S>                                                                                                      <C>
   SECTION 5.9.    Meetings..........................................................................     28
   SECTION 5.10.   Delegation of Power...............................................................     29
   SECTION 5.11.   Merger, Conversion, Consolidation or Succession to Business.......................     29

ARTICLE VI DISTRIBUTIONS

   SECTION 6.1.    Distributions.....................................................................     29

ARTICLE VII ISSUANCE OF SECURITIES

   SECTION 7.1.    General Provisions Regarding Securities...........................................     30
   SECTION 7.2.    Paying Agent......................................................................     30

ARTICLE VIII TERMINATION OF TRUST

   SECTION 8.1.    Termination of Trust..............................................................     31

ARTICLE IX TRANSFER OF INTERESTS

   SECTION 9.1.    Transfer of Securities............................................................     32
   SECTION 9.2.    Transfer of Certificates..........................................................     32
   SECTION 9.3.    Deemed Security Holders...........................................................     32
   SECTION 9.4.    Book Entry Interests..............................................................     32
   SECTION 9.5.    Notices to Clearing Agency........................................................     33
   SECTION 9.6.    Appointment of Successor Clearing Agency..........................................     33
   SECTION 9.7.    Definitive Preferred Security Certificates........................................     33
   SECTION 9.8.    Mutilated, Destroyed, Lost or Stolen Certificates.................................     34

ARTICLE X LIMITATION OF LIABILITY OF HOLDERS OF SECURITIES, TRUSTEES OR OTHERS

   SECTION 10.1.   Liability.........................................................................     35
   SECTION 10.2.   Exculpation.......................................................................     35
   SECTION 10.3.   Fiduciary Duty....................................................................     36
   SECTION 10.4.   Indemnification...................................................................     37
   SECTION 10.5.   Outside Businesses................................................................     39

ARTICLE XI ACCOUNTING

   SECTION 11.1.   Fiscal Year.......................................................................     40
   SECTION 11.2.   Certain Accounting Matters........................................................     40
   SECTION 11.3.   Banking...........................................................................     40
   SECTION 11.4.   Withholding.......................................................................     41

ARTICLE XII AMENDMENTS AND MEETINGS

   SECTION 12.1.   Amendments........................................................................     41
   SECTION 12.2.   Meetings of the Holders of Securities; Action by Written Consent..................     43

ARTICLE XIII REPRESENTATIONS OF PROPERTY TRUSTEE AND DELAWARE TRUSTEE

   SECTION 13.1.   Representations and Warranties of Property Trustee................................     44
</TABLE>

                                       ii
<PAGE>

                                TABLE OF CONTENTS
                                   (continued)
<TABLE>
<S>                                                                                                       <C>
   SECTION 13.2.   Representations and Warranties of Delaware Trustee................................     45

ARTICLE XIV MISCELLANEOUS

   SECTION 14.1.   Notices...........................................................................     46
   SECTION 14.2.   Governing Law.....................................................................     47
   SECTION 14.3.   Intention of the Parties..........................................................     47
   SECTION 14.4.   Headings..........................................................................     47
   SECTION 14.5.   Successors and Assigns............................................................     47
   SECTION 14.6.   Partial Enforceability............................................................     47
   SECTION 14.7.   Counterparts......................................................................     47
</TABLE>

                                      iii
<PAGE>

ANNEX I         TERMS OF SECURITIES

EXHIBIT A-1     FORM OF PREFERRED SECURITY CERTIFICATE

EXHIBIT A-2     FORM OF COMMON SECURITY CERTIFICATE

EXHIBIT B       SPECIMEN OF DEBENTURE

EXHIBIT C       PURCHASE AGREEMENT

                                       iv
<PAGE>

                             CROSS-REFERENCE TABLE*

<TABLE>
<CAPTION>
                                                     SECTION OF
SECTION OF TRUST                                 OF 1939, AS AMENDED
 INDENTURE ACT                                       AGREEMENT
----------------                                 -------------------
<S>                                              <C>
310 (a)                                          5.3(a)
310 (c)                                          Inapplicable
311 (c)                                          Inapplicable
312 (a)                                          2.2(a)
312 (b)                                          2.2(b)
313                                              2.3
314 (a)                                          2.4
314 (b)                                          Inapplicable
314 (c)                                          2.5
314 (d)                                          Inapplicable
314 (f)                                          Inapplicable
315 (a)                                          3.9(b)
315 (c)                                          3.9(a)
315 (d)                                          3.9(a)
316 (a)                                          Annex I
316 (c)                                          3.6(e)
</TABLE>

----------
* This Cross-Reference Table does not constitute part of the Agreement and shall
not affect the interpretation of any of its terms or provisions.

                                       v
<PAGE>

                              AMENDED AND RESTATED

                                 TRUST AGREEMENT

                         W. R. BERKLEY CAPITAL TRUST II

                                  July 26, 2005

      AMENDED AND RESTATED TRUST AGREEMENT (this "Agreement") dated and
effective as of July 26, 2005, by the Trustees (as defined herein), the Sponsor
(as defined herein) and by the holders, from time to time, of undivided
beneficial interests in the assets of the Trust (as defined herein) to be issued
pursuant to this Agreement;

      WHEREAS, the Trustees and the Sponsor established W. R. Berkley Capital
Trust II (the "Trust"), a trust under the Delaware Statutory Trust Act, pursuant
to a Trust Agreement dated as of March 22, 2001 (the "Original Agreement") and a
Certificate of Trust filed with the Secretary of State of the State of Delaware
on March 22, 2001 (the "Certificate of Trust"), for the sole purpose of issuing
and selling certain securities representing undivided beneficial interests in
the assets of the Trust and investing the proceeds thereof in certain Debentures
of the Sponsor;

      WHEREAS, prior to the execution hereof, no interests in the Trust have
been issued;

      WHEREAS, all of the Trustees and the Sponsor, by this Agreement, amend and
restate each and every term and provision of the Original Agreement; and

      NOW, THEREFORE, it being the intention of the parties hereto to continue
the Trust as a statutory trust under the Statutory Trust Act and that this
Agreement constitute the governing instrument of such statutory trust, the
Trustees declare that all assets contributed to the Trust will be held in trust
for the benefit of the holders, from time to time, of the securities
representing undivided beneficial interests in the assets of the Trust issued
hereunder, subject to the provisions of this Agreement.

                                   ARTICLE I
                         INTERPRETATION AND DEFINITIONS

      SECTION 1.1 Definitions. Unless the context otherwise requires:

            (a) Capitalized terms used in this Agreement but not defined in the
      preamble above have the respective meanings assigned to them in this
      Section 1.1;

            (b) a term defined anywhere in this Agreement has the same meaning
      throughout;

            (c) all references to "the Agreement" or "this Agreement" are to
      this Agreement as modified, supplemented or amended from time to time;

            (d) all references in this Agreement to Articles and Sections and
      Annexes and Exhibits are to Articles and Sections of and Annexes and
      Exhibits to this Agreement

                                       1
<PAGE>

      unless otherwise specified and all references in this Agreement to the
      "terms of the Securities" are to the terms of the Securities as set forth
      in Annex I hereto;

            (e) a term defined in the Trust Indenture Act has the same meaning
      when used in this Agreement unless otherwise defined in this Agreement or
      unless the context otherwise requires; and

            (f) a reference to the singular includes the plural and vice versa.

      "Administrative Trustee" has the meaning set forth in Section 5.1.

      "Affiliate" has the same meaning as given to that term in Rule 405 of the
Securities Act or any successor rule thereunder.

      "Agent" means any Paying Agent.

      "Authorized Officer" of a Person means any Person that is authorized to
bind such Person.

      "Book Entry Interest" means a beneficial interest in a Global Certificate,
ownership and transfers of which shall be maintained and made through book
entries by a Clearing Agency as described in Section 9.4.

      "Business Day" means any day other than a day on which banking
institutions in New York, New York or Wilmington, Delaware, are authorized or
required by law or executive order to close.

      "Certificate" means a Common Security Certificate or a Preferred Security
Certificate.

      "Clearing Agency" means an organization registered as a "Clearing Agency"
pursuant to Section 17A of the Exchange Act that is acting as depositary for the
Preferred Securities and in whose name or in the name of a nominee of that
organization shall be registered a Global Certificate and which shall undertake
to effect book entry transfers and pledges of the Preferred Securities.

      "Clearing Agency Participant" means a broker, dealer, bank, other
financial institution or other Person for whom from time to time the Clearing
Agency effects book entry transfers and pledges of securities deposited with the
Clearing Agency.

      "Closing Date" means the "Closing Date" under the Purchase Agreement.

      "Code" means the Internal Revenue Code of 1986, as amended from time to
time, or any successor legislation.

      "Commission" means the Securities and Exchange Commission.

      "Common Security" has the meaning specified in Section 7.1.

                                       2
<PAGE>

      "Common Securities Guarantee" means the Common Securities Guarantee
Agreement, dated as of July 26, 2005, of the Sponsor in respect of the Common
Securities.

      "Common Security Certificate" means a definitive certificate in fully
registered form, substantially in the form of Exhibit A-2, representing a Common
Security.

      "Company Indemnified Person" means (a) any Administrative Trustee; (b) any
Affiliate of any Administrative Trustee; (c) any officers, directors,
shareholders, members, partners, employees, representatives or agents of any
Administrative Trustee; or (d) any officer, employee or agent of the Trust or
its Affiliates.

      "Corporate Trust Office" means the office of the Property Trustee at which
the corporate trust business of the Preferred Guarantee Trustee shall, at any
particular time, be principally administered, which office at the date of
execution of this Agreement located at

      The Bank of New York
      101 Barclay Street, 8W
      New York, NY 10286
      Attention: Corporate Trust Administration

      "Covered Person" means: (a) any officer, director, shareholder, partner,
member, representative, employee or agent of (i) the Trust or (ii) the Trust's
Affiliates; and (b) any Holder of Securities.

      "Debenture Issuer" means W. R. Berkley Corporation, a Delaware
corporation, in its capacity as issuer of the Debentures under the Indenture.

      "Date of Delivery" is defined in the Purchase Agreement.

      "Debenture Trustee" means The Bank of New York, as trustee under the
Indenture until a successor is appointed thereunder, and thereafter such
successor trustee.

      "Debentures" means the series of Debentures to be issued by the Sponsor
under the Indenture and to be held by the Property Trustee, a specimen
certificate for such series of Debentures being substantially in the form of
Exhibit B.

      "Delaware Trustee" has the meaning set forth in Section 5.2.

      "Definitive Preferred Security Certificates" has the meaning set forth in
Section 9.4.

      "Depositary" means The Depository Trust Company, the initial Clearing
Agency.

      "Direction" by a Person means a written direction signed:

            (a) if the Person is a natural person, by that Person; or

            (b) in any other case, in the name of such Person by one or more
      Authorized Officers of such Person.

                                       3
<PAGE>

      "Distribution" means a distribution payable to Holders of Securities in
accordance with Section 6.1.

      "Event of Default" in respect of the Securities means an Event of Default
(as defined in the Indenture) has occurred and is continuing in respect of the
Debentures.

      "Exchange Act" means the Securities Exchange Act of 1934, as amended from
time to time, or any successor legislation.

      "Fiduciary Indemnified Person" has the meaning set forth in Section
10.4(b).

      "Global Certificate" has the meaning set forth in Section 9.4.

      "Holder" means a Person in whose name a Certificate representing a
Security is registered, such Person being a beneficial owner within the meaning
of the Statutory Trust Act.

      "Indemnified Person" means a Company Indemnified Person or a Fiduciary
Indemnified Person.

      "Indenture" means the Subordinated Indenture dated as of July 26, 2005,
from the Debenture Issuer to the Debenture Trustee, and any Subordinated
Indenture supplemental thereto pursuant to which the Debentures are to be issued
(including, without limitation, the Supplemental Indenture No. 1, dated as of
July 26, 2005 between the Debenture Issuer and the Debenture Trustee).

      "Investment Company" means an investment company as defined in the
Investment Company Act.

      "Investment Company Act" means the Investment Company Act of 1940, as
amended from time to time, or any successor legislation.

      "Investment Company Event" has the meaning set forth in Annex I hereto.

      "Legal Action" has the meaning set forth in Section 3.6(g).

      "Majority in liquidation amount of the Securities" means, except as
provided in the terms of the Preferred Securities or by the Trust Indenture Act,
Holder(s) of outstanding Securities voting together as a single class or, as the
context may require, Holders of outstanding Preferred Securities or Holders of
outstanding Common Securities voting separately as a class, who are the record
owners of more than 50% of the aggregate liquidation amount (including the
stated amount that would be paid on redemption, liquidation or otherwise, plus
accrued and unpaid Distributions to the date upon which the voting percentages
are determined) of all outstanding Securities of the relevant class.

      "Ministerial Action" has the meaning set forth in Annex I.

                                       4
<PAGE>

      "Officers' Certificate" means, with respect to any Person, a certificate
signed by two Authorized Officers of such Person; provided that any Officers'
Certificate delivered with respect to compliance with a condition or covenant
provided for in this Agreement shall include:

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

            (b) a brief statement of the nature and scope of the examination or
      investigation undertaken by each officer in rendering such certificate;

            (c) a statement that each such officer has made such examination or
      investigation as, in such officer's opinion, is necessary to enable such
      officer 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 officer,
      such condition or covenant has been complied with.

      "Option Preferred Securities" is defined in the Purchase Agreement.

      "Paying Agent" has the meaning specified in Section 7.2.

      "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

      "Preferred Securities Guarantee" means the Preferred Securities Guarantee
Agreement, dated as of July 26, 2005, of the Sponsor in respect of the Preferred
Securities.

      "Preferred Security" has the meaning specified in Section 7.1.

      "Preferred Security Beneficial Owner" means, with respect to a Book Entry
Interest, a Person who is the beneficial owner of such Book Entry Interest, as
reflected on the books of the Clearing Agency, or on the books of a Person
maintaining an account with such Clearing Agency (directly as a Clearing Agency
Participant or as an indirect participant, in each case in accordance with the
rules of such Clearing Agency).

      "Preferred Security Certificate" means a certificate representing a
Preferred Security substantially in the form of Exhibit A-1.

      "Property Trustee" means the Trustee meeting the eligibility requirements
set forth in Section 5.3.

      "Property Trustee Account" has the meaning set forth in Section 3.8(c).

      "Purchase Agreement" means the Purchase Agreement for the offering and
sale of Preferred Securities in the form of Exhibit C.

                                       5
<PAGE>

      "Quorum" means a majority of the Administrative Trustees or, if there are
only two Administrative Trustees, both of them.

      "Related Party" means, with respect to the Sponsor, any direct or indirect
wholly owned subsidiary of the Sponsor or any other Person that owns, directly
or indirectly, 100% of the outstanding voting securities of the Sponsor.

      "Responsible Officer" means, with respect to the Property Trustee, any
officer within the corporate trust department of the Property Trustee, including
any vice-president, any assistant vice-president, any assistant secretary, the
treasurer, any assistant treasurer or other officer of the Property Trustee
customarily performing functions similar to those performed by any of the above
designated officers, and also means, with respect to a particular corporate
trust matter, any other officer to whom such matter is referred because of that
officer's knowledge of and familiarity with the particular subject.

      "Rule 3a-5" means Rule 3a-5 under the Investment Company Act.

      "Securities" means the Common Securities and the Preferred Securities.

      "Securities Act" means the Securities Act of 1933, as amended from time to
time or any successor legislation.

      "Special Event" has the meaning set forth in Annex I hereto.

      "Sponsor" means W. R. Berkley Corporation, a Delaware corporation, or any
successor entity in a merger, consolidation or amalgamation, in its capacity as
sponsor of the Trust (and in its capacity as Depositor of the Trust under the
Original Agreement).

      "Statutory Trust Act" means Chapter 38 of Title 12 of the Delaware Code,
12 Del. Code Section 3801 et seq., as it may be amended from time to time, or
any successor legislation.

      "Super Majority" has the meaning set forth in Section 2.6 (a) (ii).

      "Tax Event" has the meaning set forth in Annex I hereto.

      "10% in liquidation amount of the Securities" means, except as provided in
the terms of the Preferred Securities or by the Trust Indenture Act, Holder(s)
of outstanding Securities voting together as a single class or, as the context
may require, Holders of outstanding Preferred Securities or Holders of
outstanding Common Securities voting separately as a class, who are the record
owners of 10% or more of the aggregate liquidation amount (including the stated
amount that would be paid on redemption, liquidation or otherwise, plus accrued
and unpaid Distributions to the date upon which the voting percentages are
determined) of all outstanding Securities of the relevant class.

      "Treasury Regulations" means the income tax regulations, including
temporary and proposed regulations, promulgated under the Code by the United
States Treasury, as such regulations may be amended from time to time (including
corresponding provisions of succeeding regulations).

                                       6
<PAGE>

      "Trustee" or "Trustees" means each Person who has signed this Agreement as
a trustee, so long as such Person shall continue as a trustee of the Trust in
accordance with the terms hereof, and all other Persons who may from time to
time be duly appointed, qualified and serving as Trustees in accordance with the
provisions hereof, and references herein to a Trustee or the Trustees shall
refer to such Person or Persons solely in their capacity as trustees hereunder.

      "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended
from time to time, or any successor legislation.

      "Trust Securities" means, collectively, the Common Securities and
Preferred Securities issued by the Trust.

                                   ARTICLE II
                               TRUST INDENTURE ACT

      SECTION 2.1. Trust Indenture Act; Application.

            (a) This Agreement is subject to the provisions of the Trust
      Indenture Act that are required to be part of this Agreement and shall, to
      the extent applicable, be governed by such provisions.

            (b) The Property Trustee shall be the only Trustee which is a
      Trustee for the purposes of the Trust Indenture Act.

            (c) If and to the extent that any provision of this Agreement
      limits, qualifies or conflicts with the duties imposed by Section 310 to
      317, inclusive, of the Trust Indenture Act, such imposed duties shall
      control.

            (d) The application of the Trust Indenture Act to this Agreement
      shall not affect the nature of the Securities as equity securities
      representing undivided beneficial interests in the assets of the Trust.

      SECTION 2.2. Lists of Holders of Securities.

            (a) The Sponsor and the Administrative Trustees on behalf of the
      Trust shall provide the Property Trustee (i) within 14 days after each
      record date for payment of Distributions, a list, in such form as the
      Property Trustee may reasonably require, of the names and addresses of the
      Holders of the Securities ("List of Holders") as of such record date,
      provided that neither the Sponsor nor the Administrative Trustees, on
      behalf of the Trust, shall be obligated to provide such List of Holders at
      any time the List of Holders does not differ from the most recent List of
      Holders given to the Property Trustee by the Sponsor and the
      Administrative Trustees on behalf of the Trust, and (ii) at any other
      time, within 30 days of receipt by the Trust of a written request for a
      List of Holders as of a date no more than 14 days before such List of
      Holders is given to the Property Trustee. The Property Trustee shall
      preserve, in as current a form as is reasonably practicable, all
      information contained in Lists of Holders given to it or which it receives
      in the capacity as Paying Agent (if acting in such capacity); provided
      that the Property Trustee may destroy any List of Holders previously given
      to it on receipt of a new List of Holders.

                                       7
<PAGE>

            (b) The Property Trustee shall comply with its obligations under
      Sections 311(a), 311(b) and 312(b) of the Trust Indenture Act.

      SECTION 2.3. Reports by the Property Trustee. Within 60 days after May 15
of each year, the Property Trustee shall provide to the Holders of the Preferred
Securities such reports as are required by Section 313 of the Trust Indenture
Act, if any, in the form and in the manner provided by Section 313 of the Trust
Indenture Act. The Property Trustee shall also comply with the requirements of
Section 313(d) of the Trust Indenture Act.

      SECTION 2.4. Periodic Reports to Property Trustee. Each of the Sponsor and
the Administrative Trustees, on behalf of the Trust, shall provide to the
Property Trustee and the Holders such documents, reports and information as
required by Section 314 (if any) of the Trust Indenture Act and the compliance
certificate required by such Section 314 of the Trust Indenture Act in the form,
in the manner and at the times required thereby. Delivery of such reports,
information and documents to the Property Trustee is for informational purposes
only and the Property Trustee's receipt of such shall not constitute
constructive notice of any information contained therein or determinable from
information contained therein, including the Sponsor's and the Administrative
Trustees' compliance with any of their covenants hereunder (as to which the
Property Trustee is entitled to rely exclusively on Officers' Certificates).

      SECTION 2.5. Evidence of Compliance with Conditions Precedent. Each of the
Sponsor and the Administrative Trustees, on behalf of the Trust, shall provide
to the Property Trustee such evidence of compliance with any conditions
precedent, if any, provided for in this Agreement that relate to any of the
matters set forth in Section 314(c) of the Trust Indenture Act. Any certificate
or opinion required to be given by an officer pursuant to Section 314(c)(1) may
be given in the form of an Officers' Certificate.

      SECTION 2.6. Events of Default; Waiver.

            (a) The Holders of a Majority in liquidation amount of Preferred
      Securities may, by vote, on behalf of the Holders of all of the Preferred
      Securities, waive any past Event of Default in respect of the Preferred
      Securities and its consequences, provided that, if the underlying Event of
      Default under the Indenture:

                  (i) is not waivable under the Indenture, the Event of Default
         under the Agreement shall also not be waivable; or

                  (ii) requires the consent or vote of greater than a majority
         in principal amount of the holders of the Debentures (a "Super
         Majority") to be waived under the Indenture, the Event of Default under
         the Agreement may only be waived by the vote of the Holders of at least
         the proportion in liquidation amount of the Preferred Securities that
         the relevant Super Majority represents of the aggregate principal
         amount of the Debentures outstanding.

      The foregoing provisions of this Section 2.6(a) shall be in lieu of
Section 316(a)(1)(B) of the Trust Indenture Act and such Section 316(a)(1)(B) of
the Trust Indenture Act is hereby expressly excluded from this Agreement and the
Securities, as permitted by the Trust Indenture Act. Upon such waiver, any such
default shall cease to exist, and any Event of Default with

                                       8
<PAGE>

respect to the Preferred Securities arising therefrom shall be deemed to have
been cured, for every purpose of this Agreement, but no such waiver shall extend
to any subsequent or other default or Event of Default with respect to the
Preferred Securities or impair any right consequent thereon. Any waiver by the
Holders of the Preferred Securities of an Event of Default with respect to the
Preferred Securities shall also be deemed to constitute a waiver by the Holders
of the Common Securities of any such Event of Default with respect to the Common
Securities for all purposes of this Agreement without any further act, vote, or
consent of the Holders of the Common Securities.

            (b) The Holders of a Majority in liquidation amount of the Common
      Securities may, by vote, on behalf of the Holders of all of the Common
      Securities, waive any past Event of Default with respect to the Common
      Securities and its consequences, provided that, if the underlying Event of
      Default under the Indenture:

                  (i) is not waivable under the Indenture, except where the
         Holders of the Common Securities are deemed to have waived such Event
         of Default under the Agreement as provided below in this Section
         2.6(b), the Event of Default under the Agreement shall also not be
         waivable; or

                  (ii) requires the consent or vote of a Super Majority to be
         waived, except where the Holders of the Common Securities are deemed to
         have waived such Event of Default under the Agreement as provided below
         in this Section 2.6(b), the Event of Default under the Agreement may
         only be waived by the vote of the Holders of at least the proportion in
         aggregate liquidation amount of the Common Securities that the relevant
         Super Majority represents of the aggregate principal amount of the
         Debentures outstanding;

provided further, that each Holder of Common Securities will be deemed to have
waived any such Event of Default and all Events of Default with respect to the
Common Securities and its consequences until all Events of Default with respect
to the Preferred Securities have been cured, waived or otherwise eliminated, and
until such Events of Default have been so cured, waived or otherwise eliminated,
the Property Trustee will be deemed with respect to the Preferred Securities to
be acting solely on behalf of the Holders of the Preferred Securities and only
the Holders of the Preferred Securities will have the right to direct the
Property Trustee in accordance with the terms of the Securities. The foregoing
provisions of this Section 2.6(b) shall be in lieu of Sections 316(a)(1)(A) and
316(a)(1)(B) of the Trust Indenture Act and such Sections 316(a)(1)(A) and
316(a)(1)(B) of the Trust Indenture Act are hereby expressly excluded from this
Agreement and the Securities, as permitted by the Trust Indenture Act. Subject
to the foregoing provisions of this Section 2.6(b), upon such waiver, any such
default shall cease to exist and any Event of Default with respect to the Common
Securities arising therefrom shall be deemed to have been cured for every
purpose of this Agreement, but no such waiver shall extend to any subsequent or
other default or Event of Default with respect to the Common Securities or
impair any right consequent thereon.

            (c) A waiver of an Event of Default under the Indenture by the
      Property Trustee at the written direction of the Holders of the Preferred
      Securities constitutes a waiver of the corresponding Event of Default with
      respect to the Preferred Securities

                                       9
<PAGE>

      under this Agreement. Any waiver of an Event of Default under the
      Indenture by the Property Trustee at the direction of the Holders of the
      Preferred Securities shall also be deemed to constitute a waiver by the
      Holders of the Common Securities of the corresponding Event of Default
      under this Agreement with respect to the Common Securities for all
      purposes of this Agreement without further act, vote or consent of the
      Holders of the Common Securities. The foregoing provisions of this Section
      2.6(c) shall be in lieu of Section 316(a)(1)(B) of the Trust Indenture Act
      and such Section 316(a)(1)(B) of the Trust Indenture Act is hereby
      expressly excluded from this Agreement and the Securities, as permitted by
      the Trust Indenture Act.

      SECTION 2.7. Event of Default; Notice.

            (a) The Property Trustee shall, within five (5) Business Days after
      a Responsible Officer of the Property Trustee obtains actual knowledge of
      the occurrence of an Event of Default, transmit by mail, first class
      postage prepaid, to the Holders of the Securities, notices of all defaults
      with respect to the Securities actually known to a Responsible Officer of
      the Property Trustee, unless such defaults have been cured before the
      giving of such notice (the term "defaults" for the purposes of this
      Section 2.7 being hereby defined to be an Event of Default as defined in
      the Indenture, not including any periods of grace provided for therein and
      irrespective of the giving of any notice provided therein); provided that,
      except with respect to a default in the payment of principal of (or
      premium, if any) or interest on any of the Debentures or in the payment of
      any sinking fund installment established for the Debentures, the Property
      Trustee shall be protected in withholding such notice if and so long as a
      Responsible Officer of the Property Trustee in good faith determines that
      the withholding of such notice is in the interests of the Holders of the
      Securities.

            (b) The Property Trustee shall not be deemed to have knowledge of
      any default except:

                  (i) a default under Sections 5.1 or 5.3 of the Indenture; or

                  (ii) any default as to which the Property Trustee shall have
         received written notice or of which a Responsible Officer of the
         Property Trustee charged with the administration of the Agreement shall
         have actual knowledge.

                                  ARTICLE III
                                  ORGANIZATION

      SECTION 3.1. Name. The Trust is named "W. R. Berkley Capital Trust II," as
such name may be modified from time to time by the Administrative Trustees
following written notice to the Holders of Securities and the filing of a
certificate of amendment under the Statutory Trust Act. The Trust's activities
may be conducted under the name of the Trust or any other name deemed advisable
by the Administrative Trustees.

      SECTION 3.2. Office. The address of the principal office of the Trust is
475 Steamboat Road, Greenwich, Connecticut 06830. On ten Business Days' written
notice to the

                                       10
<PAGE>

other Trustees and to the Holders of the Securities, the Administrative Trustees
may designate another principal office.

      SECTION 3.3. Purpose. The exclusive purposes and functions of the Trust
are (i) to issue and sell the Preferred Securities and the Common Securities
representing undivided beneficial interests in the assets of the Trust, (ii) to
use the gross proceeds from the sale of the Securities to acquire the Debentures
and (iii) to engage in only those other activities necessary or incidental
thereto. The Trust shall not borrow money, issue debt or reinvest proceeds
derived from investments, pledge any of its assets, or otherwise undertake (or
permit to be undertaken) any activity that would cause the Trust not to be
classified for United States federal income tax purposes as a grantor trust.

      The Trustees, the Sponsor and the Holders of the Preferred Securities and
Common Securities (by their acceptance of such Securities) agree not to take any
position for United States federal income tax purposes which is contrary to the
classification of the Trust as a grantor trust.

      SECTION 3.4. Authority. Subject to the limitations provided in this
Agreement and to the specific duties of the Property Trustee and the Sponsor,
the Administrative Trustees shall have exclusive and complete authority to carry
out the purposes of the Trust. An action taken by the Administrative Trustees in
accordance with their powers shall constitute the act of and serve to bind the
Trust and an action taken by the Property Trustee on behalf of the Trust in
accordance with its powers shall constitute the act of and serve to bind the
Trust. In dealing with the Trustees acting on behalf of the Trust, no person
shall be required to inquire into the authority of the Trustees to bind the
Trust. Persons dealing with the Trust are entitled to rely conclusively on the
power and authority of the Trustees as set forth in this Agreement.

      SECTION 3.5. Title to Property of the Trust. Except as provided in Section
3.8 with respect to the Debentures and the Property Trustee Account or as
otherwise provided in this Agreement, legal title to all assets of the Trust
shall be vested in the Trust. The Holders shall not have legal title to any part
of the assets of the Trust, but shall have an undivided beneficial interest in
the assets of the Trust.

      SECTION 3.6. Powers and Duties of the Administrative Trustees. The
Administrative Trustees shall have the exclusive power, duty and authority to
cause the Trust to engage in the following activities:

            (a) to issue and sell the Preferred Securities and the Common
      Securities in accordance with this Agreement; provided, however, that the
      Trust may issue no more than one series of Preferred Securities and no
      more than one series of Common Securities, and, provided further, that
      there shall be no interests in the Trust other than the Securities, and
      the issuance of Securities shall be limited to a simultaneous issuance of
      both Preferred Securities and Common Securities on the Closing Date and on
      the Date of Delivery with respect to Option Preferred Securities;

            (b) in connection with the issue and sale of the Preferred
      Securities, at the direction of the Sponsor, to:

                                       11
<PAGE>

                  (i) execute and file with the Commission the registration
         statement on Form S-3 prepared by the Sponsor, including any amendments
         thereto, pertaining to the Preferred Securities;

                  (ii) execute and file any documents prepared by the Sponsor,
         or take any acts as determined by the Sponsor to be necessary or
         advisable in order to qualify or register all or part of the Preferred
         Securities in any State in which the Sponsor has determined to qualify
         or register such Preferred Securities for sale;

                  (iii) execute and file an application, prepared by the
         Sponsor, to the New York Stock Exchange, Inc. or any other national
         stock exchange or the Nasdaq Stock Market's National Market for listing
         upon notice of issuance of any Preferred Securities pursuant to Section
         3.8;

                  (iv) execute and file with the Commission a registration
         statement on Form 8-A, including any amendments thereto, prepared by
         the Sponsor, relating to the registration of the Preferred Securities
         under Section 12(b) of the Exchange Act; and

                  (v) execute and enter into the (or perform in accordance with
         the previously executed) Purchase Agreement providing for the sale of
         the Preferred Securities.

            (c) to acquire the Debentures with the proceeds of the sale of the
      Preferred Securities and the Common Securities; provided, however, that
      the Administrative Trustees shall cause legal title to the Debentures to
      be held of record in the name of the Property Trustee for the benefit of
      the Holders of the Preferred Securities and the Holders of Common
      Securities pursuant to Section 3.8;

            (d) to cause the Trust to enter into, and to execute, deliver and
      perform on behalf of the Trust, such agreements as may be necessary or
      desirable in connection with the purposes and function of the Trust,
      including agreements with the Paying Agent and a Common Securities
      subscription agreement or purchase agreement between the Trust and the
      Sponsor;

            (e) to give the Sponsor and the Property Trustee prompt written
      notice of the occurrence of a Special Event; provided that the
      Administrative Trustees shall consult with the Sponsor and the Property
      Trustee before taking or refraining from taking any Ministerial Action in
      relation to a Tax Event;

            (f) to establish a record date with respect to all actions to be
      taken hereunder that require a record date to be established, including
      and with respect to, for the purposes of Section 316(c) of the Trust
      Indenture Act, Distributions, voting rights, redemptions and exchanges,
      and to issue relevant notices to the Holders of Preferred Securities and
      Holders of Common Securities as to such actions and applicable record
      dates;

            (g) to take all actions and perform such duties as may be required
      of the Administrative Trustees pursuant to the terms of the Securities;

                                       12
<PAGE>

            (h) to bring or defend, pay, collect, compromise, arbitrate, resort
      to legal action, or otherwise adjust claims or demands of or against the
      Trust ("Legal Action"), unless pursuant to Section 3.8(e), the Property
      Trustee has the exclusive power to bring such Legal Action;

            (i) to employ or otherwise engage employees and agents (who may be
      designated as officers with titles) and managers, contractors, advisors,
      and consultants and pay reasonable compensation for such services;

            (j) to cause the Trust to comply with the Trust's obligations under
      the Trust Indenture Act;

            (k) to give the certificate required by Section 314(a)(4) of the
      Trust Indenture Act to the Property Trustee, which certificate may be
      executed by any Administrative Trustee;

            (l) to incur expenses that are necessary, appropriate, convenient or
      incidental to carry out any of the purposes of the Trust;

            (m) to act as, or appoint another Person to act as, registrar and
      transfer agent for the Securities;

            (n) to give prompt written notice to the Property Trustee and to the
      Holders of the Securities of any notice received from the Debenture Issuer
      of its election to defer payments of interest on the Debentures by
      extending the interest payment period under the Indenture;

            (o) to take all action that may be necessary or appropriate for the
      preservation and the continuation of the Trust's valid existence, rights,
      franchises and privileges as a statutory trust under the laws of the State
      of Delaware and of each other jurisdiction in which such existence is
      necessary to protect the limited liability of the Holders of the Preferred
      Securities or to enable the Trust to effect the purposes for which the
      Trust was created;

            (p) to take any action, not inconsistent with this Agreement or with
      applicable law, that the Administrative Trustees determine in their
      discretion to be necessary or desirable in carrying out the activities of
      the Trust as set out in this Section 3.6, including, but not limited to:

                  (i) causing the Trust not to be deemed to be an Investment
         Company required to be registered under the Investment Company Act;

                  (ii) causing the Trust to continue to be classified for United
         States federal income tax purposes as a grantor trust; and

                  (iii) cooperating with the Debenture Issuer to ensure that the
         Debentures will be treated as indebtedness of the Debenture Issuer for
         United States federal income tax purposes,

                                       13
<PAGE>

provided that such action does not adversely affect the interests of the Holders
in any material respect;

            (q) to take all action necessary to cause all applicable tax returns
      and tax information reports that are required to be filed with respect to
      the Trust to be duly prepared and filed by the Administrative Trustees, on
      behalf of the Trust; and

            (r) to execute all documents or instruments, perform all duties and
      powers, and do all things for and on behalf of the Trust in all matters
      necessary or incidental to the foregoing.

      The Administrative Trustees must exercise the powers set forth in this
Section 3.6 in a manner that is consistent with the purposes and functions of
the Trust set out in Section 3.3, and the Administrative Trustees shall not take
any action that is inconsistent with the purposes and functions of the Trust set
forth in Section 3.3.

      Subject to this Section 3.6, the Administrative Trustees shall have none
of the powers or the authority of the Property Trustee set forth in Section 3.8.

      Any expenses incurred by the Administrative Trustees pursuant to this
Section 3.6 shall be reimbursed by the Debenture Issuer.

      SECTION 3.7. Prohibition of Actions by the Trust and the Trustees.

            (a) The Trust shall not, and the Trustees (including the Property
      Trustee) shall not, engage in any activity other than as required or
      authorized by this Agreement. In particular, the Trust shall not and the
      Trustees (including the Property Trustee) shall cause the Trust not to:

                  (i) invest any proceeds received by the Trust from holding the
         Debentures, but shall distribute all such proceeds to Holders of
         Securities pursuant to the terms of this Agreement and of the
         Securities;

                  (ii) acquire any assets other than as expressly provided
         herein;

                  (iii) possess Trust property for other than a Trust purpose as
         set forth in Section 3.3;

                  (iv) make any loans or incur any indebtedness other than loans
         represented by the Debentures;

                  (v) possess any power or otherwise act in such a way as to
         vary the Trust assets or the terms of the Securities in any way
         whatsoever;

                  (vi) issue any securities or other evidences of beneficial
         ownership of, or beneficial interest in, the Trust other than the
         Securities; or

                                       14
<PAGE>

                  (vii) other than as provided in this Agreement (including,
         without limitation, Annex I), (A) direct the time, method and place of
         conducting any proceeding with respect to any remedy available to the
         Debenture Trustee or exercising any trust or power conferred upon the
         Debenture Trustee with respect to the Debentures, (B) waive any past
         default under the Indenture, (C) exercise any right to rescind or annul
         any declaration that the principal of all the Debentures shall be due
         and payable, or (D) consent to any amendment, modification or
         termination of the Indenture or the Debentures where such consent shall
         be required unless the Trust shall have received an opinion of
         nationally recognized tax counsel to the effect that such amendment,
         modification or termination will not cause more than an insubstantial
         risk that (x) the Trust be deemed an Investment Company required to be
         registered under the Investment Company Act or (y) for United States
         federal income tax purposes the Trust will be classified as other than
         a grantor trust as a result of such action.

      SECTION 3.8. Powers and Duties of the Property Trustee.

            (a) The legal title to the Debentures shall be held of record by the
      Property Trustee in trust for the benefit of the Holders of the
      Securities. The right, title and interest of the Property Trustee to the
      Debentures shall vest automatically in each Person who may hereafter be
      appointed as Property Trustee in accordance with Section 5.6. Such vesting
      and cessation of title shall be effective whether or not conveyancing
      documents with regard to the Debentures have been executed and delivered.

            (b) The Property Trustee shall not transfer its right, title and
      interest in the Debentures to the Administrative Trustees or to the
      Delaware Trustee (if the Property Trustee does not also act as Delaware
      Trustee).

            (c) The Property Trustee shall:

                  (i) establish and maintain a segregated non-interest bearing
         trust account (the "Property Trustee Account") in the name of and under
         the exclusive control of the Property Trustee on behalf of the Holders
         of the Securities and, upon the receipt of payments of funds made in
         respect of the Debentures held by the Property Trustee, deposit such
         funds into the Property Trustee Account and make payments to the
         Holders of the Preferred Securities and Holders of the Common
         Securities from the Property Trustee Account in accordance with Section
         6.1. Funds in the Property Trustee Account shall be held uninvested
         until disbursed in accordance with this Agreement. The Property Trustee
         Account shall be an account that is maintained with a banking
         institution the rating on whose long-term unsecured indebtedness is at
         least equal to the rating assigned to the Preferred Securities by a
         "nationally recognized statistical rating organization," as that term
         is defined for purposes of Rule 436(g)(2) under the Securities Act;

                  (ii) engage in such ministerial activities as shall be
         necessary or appropriate to effect the redemption of the Preferred
         Securities and the Common

                                       15
<PAGE>

         Securities pursuant to this Agreement (including, without limitation,
         Annex I) to the extent the Debentures are redeemed or mature; and

                  (iii) upon written notice of distribution issued by the
         Administrative Trustees in accordance with the terms of the Securities,
         engage in such ministerial activities as shall be necessary or
         appropriate to effect the distribution of the Debentures to Holders of
         Securities upon the occurrence of certain special events (as may be
         defined in the terms of the Securities) arising from a change in law or
         a change in legal interpretation or other specified circumstances
         pursuant to the terms of the Securities.

            (d) The Property Trustee shall take all actions and perform such
      duties as may be specifically required of the Property Trustee pursuant to
      the terms of the Securities.

            (e) The Property Trustee shall take any Legal Action which arises
      out of or in connection with an Event of Default of which a Responsible
      Officer of the Property Trustee has actual knowledge or the Property
      Trustee's duties and obligations under this Agreement or the Trust
      Indenture Act.

            (f) The Property Trustee shall not resign as a Trustee unless
      either:

                  (i) the Trust has been completely liquidated and the proceeds
         of the liquidation distributed to the Holders of Securities pursuant to
         the terms of the Securities; or

                  (ii) a Successor Property Trustee (as defined in Section 5.6)
         has been appointed and has accepted that appointment in accordance with
         Section 5.6.

            (g) The Property Trustee shall have the legal power to exercise all
      of the rights, powers and privileges of a holder of Debentures under the
      Indenture and, if an Event of Default actually known to a Responsible
      Officer of the Property Trustee occurs and is continuing, the Property
      Trustee shall, for the benefit of Holders of the Securities, enforce its
      rights as holder of the Debentures subject to the rights of the Holders
      pursuant to the terms of such Securities.

            (h) Subject to this Section 3.8, the Property Trustee shall have
      none of the duties, liabilities, powers or the authority of the
      Administrative Trustees set forth in Section 3.6.

      The Property Trustee must exercise the powers set forth in this Section
3.8 in a manner that is consistent with the purposes and functions of the Trust
set out in Section 3.3, and the Property Trustee shall not take any action that
is inconsistent with the purposes and functions of the Trust set out in Section
3.3.

      SECTION 3.9. Certain Duties and Responsibilities of the Property Trustee.

            (a) The Property Trustee, before the occurrence of any Event of
      Default and after the curing or waiving of all Events of Default that may
      have occurred, shall

                                       16
<PAGE>

      undertake to perform only such duties as are specifically set forth in
      this Agreement and no implied covenants shall be read into this Agreement
      against the Property Trustee. In case an Event of Default has occurred
      (that has not been cured or waived pursuant to Section 2.6) of which a
      Responsible Officer of the Property Trustee has actual knowledge, the
      Property 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 person would exercise or use under the
      circumstances in the conduct of his or her own affairs.

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

                  (i) prior to the occurrence of an Event of Default and after
         the curing or waiving of all such Events of Default that may have
         occurred:

            (A) the duties and obligations of the Property Trustee shall be
      determined solely by the express provisions of this Agreement and the
      Property Trustee shall not be liable except for the performance of such
      duties and obligations as are specifically set forth in this Agreement,
      and no implied covenants or obligations shall be read into this Agreement
      against the Property Trustee; and

            (B) in the absence of bad faith on the part of the Property Trustee,
      the Property Trustee may conclusively rely, as to the truth of the
      statements and the correctness of the opinions expressed therein, upon any
      certificates or opinions furnished to the Property Trustee and conforming
      to the requirements of this Agreement; but in the case of any such
      certificates or opinions that by any provision hereof are specifically
      required to be furnished to the Property Trustee, the Property Trustee
      shall be under a duty to examine the same to determine whether or not they
      conform to the requirements of this Agreement (but need not confirm or
      investigate the accuracy of mathematical calculations or other facts
      stated therein);

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

                  (iii) the Property 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 of not less than a
         Majority in liquidation amount of the Securities relating to the time,
         method and place of conducting any proceeding for any remedy available
         to the Property Trustee, or exercising any trust or power conferred
         upon the Property Trustee under this Agreement;

                  (iv) no provision of this Agreement shall require the Property
         Trustee to expend or risk its own funds or otherwise incur any
         liability in the performance of any of its duties or in the exercise of
         any of its rights or powers, if it shall have reasonable grounds for
         believing that the repayment of such funds or liability is not

                                       17
<PAGE>

         reasonably assured to it under the terms of this Agreement or indemnity
         reasonably satisfactory to the Property Trustee against such risk or
         liability is not reasonably assured to it;

                  (v) the Property Trustee's sole duty with respect to the
         custody, safe keeping and physical preservation of the Debentures and
         the Property Trustee Account shall be to deal with such property in a
         similar manner as the Property Trustee deals with similar property for
         its own account, subject to the protections and limitations on
         liability afforded to the Property Trustee under this Agreement and the
         Trust Indenture Act;

                  (vi) the Property Trustee shall have no duty or liability for
         or with respect to the value, genuineness, existence or sufficiency of
         the Debentures or the payment of any taxes or assessments levied
         thereon or in connection therewith;

                  (vii) the Property Trustee shall not be liable for any
         interest on any money received by it except as it may otherwise agree
         in writing with the Sponsor. Money held by the Property Trustee need
         not be segregated from other funds held by it except in relation to the
         Property Trustee Account maintained by the Property Trustee pursuant to
         Section 3.8(c)(i) and except to the extent otherwise required by law;
         and

                  (viii) the Property Trustee shall not be responsible for
         monitoring the compliance by the Administrative Trustees or the Sponsor
         with their respective duties under this Agreement, nor shall the
         Property Trustee be liable for any default or misconduct of the
         Administrative Trustees or the Sponsor.

      SECTION 3.10. Certain Rights of Property Trustee.

            (a) Subject to the provisions of Section 3.9:

                  (i) the Property Trustee may conclusively rely and shall be
         fully 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, sent or presented by the
         proper party or parties;

                  (ii) any direction or act of the Sponsor or the Administrative
         Trustees contemplated by this Agreement shall be sufficiently evidenced
         by a Direction or an Officers' Certificate;

                  (iii) whenever, in the administration of this Agreement, the
         Property Trustee shall deem it desirable that a matter be proved or
         established before taking, suffering or omitting any action hereunder,
         the Property Trustee (unless other evidence is herein specifically
         prescribed) may, in the absence of bad faith on its part, request and
         conclusively rely upon an Officers' Certificate which, upon receipt of

                                       18
<PAGE>

         such request, shall be promptly delivered by the Sponsor or the
         Administrative Trustees;

                  (iv) the Property Trustee shall have no duty to see to any
         recording, filing or registration of any instrument (including any
         financing or continuation statement or any filing under tax or
         securities laws) or any rerecording, refiling or reregistration
         thereof;

                  (v) the Property Trustee may consult with counsel or other
         experts of its selection and the advice or opinion of such counsel and
         experts with respect to legal matters or advice within the scope of
         such experts' area of expertise 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 accordance with such
         advice or opinion, it being understood that such counsel may be counsel
         to the Sponsor or any of its Affiliates, and may include any of its
         employees. The Property Trustee shall have the right at any time to
         seek instructions concerning the administration of this Agreement from
         any court of competent jurisdiction;

                  (vi) the Property 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 Holder, unless such Holder shall have
         provided to the Property Trustee security and indemnity, reasonably
         satisfactory to the Property Trustee, against the costs, expenses
         (including attorneys' fees and expenses and the expenses of the
         Property Trustee's agents, nominees or custodians) and liabilities that
         might be incurred by it in complying with such request or direction,
         including such reasonable advances as may be requested by the Property
         Trustee provided, that, nothing contained in this Section 3.10(a)(vi)
         shall be taken to relieve the Property Trustee, upon the occurrence of
         an Event of Default, of its obligation to exercise the rights and
         powers vested in it by this Agreement;

                  (vii) the Property 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,
         direction, consent, order, bond, debenture, note, other evidence of
         indebtedness or other paper or document, but the Property Trustee, in
         its discretion, may make such further inquiry or investigation into
         such facts or matters as it may see fit and, if the Property Trustee
         shall determine to make such further inquiry or investigation, it shall
         be entitled to examine the books, records and premises of the Company,
         personally or by agent or attorney at the sole cost of the Company and
         shall incur no liability or additional liability of any kind by reason
         of such inquiry or investigation;

                  (viii) the Property Trustee may execute any of the trusts or
         powers hereunder or perform any duties hereunder either directly or by
         or through agents, custodians, nominees or attorneys and the Property
         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;

                                       19
<PAGE>

                  (ix) any action taken by the Property Trustee or its agents
         hereunder shall bind the Trust and the Holders of the Securities, and
         the signature of the Property Trustee or its agents alone shall be
         sufficient and effective to perform any such action and no third party
         shall be required to inquire as to the authority of the Property
         Trustee to so act or as to its compliance with any of the terms and
         provisions of this Agreement, both of which shall be conclusively
         evidenced by the Property Trustee's or its agent's taking such action;

                  (x) whenever in the administration of this Agreement the
         Property Trustee shall deem it desirable to receive instructions with
         respect to enforcing any remedy or right or taking any other action
         hereunder, the Property Trustee (i) may request instructions from the
         Holders of the Securities which instructions may only be given by the
         Holders of the same proportion in liquidation amount of the Securities
         as would be entitled to direct the Property Trustee under the terms of
         the Securities in respect of such remedy, right or action, (ii) may
         refrain from enforcing such remedy or right or taking such other action
         until such instructions are received, and (iii) shall be fully
         protected in conclusively relying on or acting in accordance with such
         instructions;

                  (xi) except as otherwise expressly provided by this Agreement,
         the Property Trustee shall not be under any obligation to take any
         action that is discretionary under the provisions of this Agreement.

                  (xii) the Property Trustee shall not be liable for any action
         taken, suffered, or omitted to be taken by it in good faith, without
         negligence, and reasonably believed by it to be authorized or within
         the discretion or rights or powers conferred upon it by this Agreement;

                  (xiii) when the Property Trustee incurs expenses or renders
         services in connection with an Event of Default under the Indenture,
         such expenses (including the fees and expenses of its counsel) and the
         compensation for such services are intended to constitute expenses of
         administration under any bankruptcy law or law relating to creditors
         rights generally;

                  (xiv) in the event that the Property Trustee is also acting as
         Paying Agent hereunder, the rights and protections afforded to the
         Property Trustee pursuant to this Article III shall also be afforded to
         such Paying Agent;

                  (xv) in no event shall the Property Trustee be responsible or
         liable for special, indirect, or consequential loss or damage of any
         kind whatsoever (including, but not limited to, loss of profit)
         irrespective of whether the Property Trustee has been advised of the
         likelihood of such loss or damage and regardless of the form of action;
         and

                  (xvi) the rights, privileges, protections, immunities and
         benefits given to the Property Trustee, including, without limitation,
         its right to be indemnified, are

                                       20
<PAGE>

         extended to, and shall be enforceable by, the Property Trustee in each
         of its capacities hereunder, and each agent, custodian and other Person
         employed to act hereunder.

            (b)   No provision of this Agreement shall be deemed to impose any
      duty or obligation on the Property Trustee to perform any act or acts or
      exercise any right, power, duty or obligation conferred or imposed on it,
      in any jurisdiction in which it shall be illegal, or in which the Property
      Trustee shall be unqualified or incompetent in accordance with applicable
      law, to perform any such act or acts, or to exercise any such right,
      power, duty or obligation. No permissive power or authority available to
      the Property Trustee shall be construed to be a duty.

      SECTION 3.11. Delaware Trustee. Notwithstanding any other provision of
this Agreement other than Section 5.2, the Delaware Trustee shall not be
entitled to exercise any powers, nor shall the Delaware Trustee have any of the
duties and responsibilities of the Administrative Trustees or the Property
Trustee described in this Agreement. Except as set forth in Section 5.2, the
Delaware Trustee shall be a Trustee for the sole and limited purpose of
fulfilling the requirements of Section 3807 of the Statutory Trust Act and
taking such actions as are required to be taken by the Delaware Trustee under
the Statutory Trust Act. In the event that the Delaware Trustee is required to
take any action or perform any duty hereunder, the Delaware Trustee shall be
entitled to the benefits of Section 3.9(b)(ii) through (viii) and Section 3.10
of this Agreement.

      SECTION 3.12. Execution of Documents. Unless otherwise determined by the
Administrative Trustees, and except as otherwise required by the Statutory Trust
Act, any Administrative Trustee is authorized to execute on behalf of the Trust
any documents that the Administrative Trustees have the power and authority to
execute pursuant to Section 3.6; provided that, the registration statement
referred to in Section 3.6(b)(i), including any amendments thereto, shall be
signed by all of the Administrative Trustees.

      SECTION 3.13. Not Responsible for Recitals or Issuance of Securities. The
recitals contained in this Agreement and the Securities shall be taken as the
statements of the Sponsor, and the Trustees do not assume any responsibility for
their correctness. The Trustees make no representations as to the value or
condition of the property of the Trust or any part thereof. The Trustees make no
representations as to the validity or sufficiency of this Agreement or the
Securities.

      SECTION 3.14. Duration of Trust. The Trust, unless terminated earlier
pursuant to the provisions of Article VIII hereof, shall have existence for
fifty-five (55) years from the issuance of the Debentures.

      SECTION 3.15. Mergers.

            (a)   The Trust may not consolidate, amalgamate, merge with or into,
      or be replaced by, or convey, transfer or lease its properties and assets
      substantially as an entirety to any Person, except as described in
      Sections 3.15(b) and (c).

            (b)   The Trust may, with the consent of the Administrative Trustees
      (or, if there are more than two, a majority of the Administrative
      Trustees) and without the

                                       21
<PAGE>

      consent of the Holders of the Securities, the Delaware Trustee or the
      Property Trustee, consolidate, amalgamate, merge with or into, or be
      replaced by a trust organized as such under the laws of any State;
      provided that:

                  (i)   such successor entity (the "Successor Entity") either:

            (A)   expressly assumes all of the obligations of the Trust under
      the Securities; or

            (B)   substitutes for the Preferred Securities other securities
      having substantially the same terms as the Preferred Securities (the
      "Successor Securities") so long as the Successor Securities rank the same
      as the Preferred Securities rank with respect to Distributions and
      payments upon liquidation, redemption and otherwise;

                  (ii)  the Debenture Issuer expressly appoints a trustee of the
         Successor Entity that possesses the same powers and duties as the
         Property Trustee as the Holder of the Debentures;

                  (iii) the Preferred Securities or any Successor Securities are
         listed, or any Successor Securities will be listed upon notification of
         issuance, on any national securities exchange or with another
         organization on which the Preferred Securities are then listed or
         quoted;

                  (iv)  such merger, consolidation, amalgamation or replacement
         does not cause the Preferred Securities (including any Successor
         Securities) to be downgraded by any nationally recognized statistical
         rating organization;

                  (v)   such merger, consolidation, amalgamation or replacement
         does not adversely affect the rights, preferences and privileges of the
         Holders of the Securities (including any Successor Securities) in any
         material respect (other than with respect to any dilution of such
         Holders' interests in the Preferred Securities as a result of such
         merger, consolidation, amalgamation or replacement);

                  (vi)  such Successor Entity has a purpose substantially
         identical to that of the Trust;

                  (vii) prior to such merger, consolidation, amalgamation or
         replacement, the Sponsor has received an opinion of a nationally
         recognized independent counsel to the Trust experienced in such matters
         to the effect that:

            (A)   such merger, consolidation, amalgamation or replacement does
      not adversely affect the rights, preferences and privileges of the Holders
      of the Securities (including any Successor Securities) in any material
      respect (other than with respect to any dilution of the Holders' interest
      in the new entity); and

            (B)   following such merger, consolidation, amalgamation or
      replacement, neither the Trust nor the Successor Entity will be required
      to register as an Investment Company under the Investment Company Act;

                                       22
<PAGE>

            (C)   following such merger, consolidation, amalgamation or
      replacement, the Trust (or the Successor Entity) will continue to be
      classified as a grantor trust for United States federal income tax
      purposes; and

                  (viii) the Sponsor guarantees the obligations of such
         Successor Entity under the Successor Securities at least to the extent
         provided by the Preferred Securities Guarantee.

            (c)   Notwithstanding Section 3.15(b), the Trust shall not, except
      with the consent of Holders of 100% in liquidation amount of the
      Securities, consolidate, amalgamate, merge with or into, or be replaced by
      any other entity or permit any other entity to consolidate, amalgamate,
      merge with or into, or replace it if such consolidation, amalgamation,
      merger or replacement would cause the Trust or Successor Entity to be
      classified as other than a grantor trust for United States federal income
      tax purposes.

                                   ARTICLE IV
                                     SPONSOR

      SECTION 4.1. Sponsor's Purchase of Common Securities. On the Closing Date
at the same time as the Preferred Securities are sold, the Sponsor will purchase
all of the Common Securities issued by the Trust.

      SECTION 4.2. Responsibilities of the Sponsor. In connection with the issue
and sale of the Preferred Securities, the Sponsor shall have the exclusive right
and responsibility to engage in the following activities:

            (a)   to prepare for filing by the Trust with the Commission a
      registration statement on Form S-3 in relation to the Preferred
      Securities, including any amendments thereto;

            (b)   to determine the States in which to take appropriate action to
      qualify or register for sale all or part of the Preferred Securities and
      to do any and all such acts, other than actions which must be taken by the
      Trust, advise the Trust of actions it must take, and prepare for execution
      and filing any documents to be executed and filed by the Trust, as the
      Sponsor deems necessary or advisable in order to comply with the
      applicable laws of any such States;

            (c)   prepare for execution and filing by the Trust of documents or
      instruments to be delivered to the Depositary relating to the Preferred
      Securities;

            (d)   to prepare for filing by the Trust an application to the New
      York Stock Exchange or any other national stock exchange or the Nasdaq
      National Market for listing upon notice of issuance of any Preferred
      Securities;

            (e)   to prepare for filing by the Trust with the Commission a
      registration statement on Form 8-A relating to the registration of the
      Preferred Securities under Section 12(b) of the Exchange Act, including
      any amendments thereto; and

                                       23
<PAGE>

            (f)   to negotiate the terms of the Purchase Agreement providing for
      the sale of the Preferred Securities.

                                   ARTICLE V
                                    TRUSTEES

      SECTION 5.1. Number of Trustees. The number of Trustees initially shall be
four (4), and:

            (a)   at any time before the issuance of any Securities, the Sponsor
      may, by written instrument, increase or decrease the number of Trustees;

            (b)   after the issuance of any Securities, the number of Trustees
      may be increased or decreased by vote of the Holders of a Majority in
      liquidation amount of the Common Securities voting as a class at a meeting
      of the Holders of the Common Securities; provided, however, that the
      number of Trustees shall in no event be less than two (2); provided
      further that (1) one Trustee meets the requirements of Sections 5.2(a) or
      (b); (2) there shall be at least two Trustees who are employees or
      officers of, or are affiliated with, the Sponsor (each, an "Administrative
      Trustee"); and (3) at least one Trustee shall be a Property Trustee for so
      long as this Agreement is required to qualify as an indenture under the
      Trust Indenture Act, and such Trustee may also serve as Delaware Trustee
      if it meets the applicable requirements;

            (c)   after the issuance of any Securities, unless an Event of
      Default shall have occurred and be continuing, at any time or times, for
      the purpose of meeting the legal requirements of the Trust Indenture Act
      or of any jurisdiction in which any part of the property of any trust may
      at the time be located, the Holders of a Majority in liquidation amount of
      the Common Securities voting as a class at a meeting of the Holders of the
      Common Securities and the Administrative Trustee shall have power to
      appoint one or more persons either to act as a co-Trustee, jointly with
      the Property Trustee, of all or any part of the property of any trust, or
      to act as separate Trustee of any such property, in either case with such
      powers as may be provided in the instrument of appointment, and to vest in
      such person or persons in such capacity any property, title, right or
      power deemed necessary or desirable, subject to the provisions of the
      applicable restated trust agreement; and

            (d)   after the issuance of any Securities, if an Event of Default
      shall have occurred and be continuing, at any time or times, for the
      purpose of meeting the legal requirements of the Trust Indenture Act or of
      any jurisdiction in which any part of the property of any trust may at the
      time be located, the Property Trustee shall have power to appoint one or
      more persons either to act as a co-Trustee, jointly with the Property
      Trustee, of all or any part of the property of any trust, or to act as
      separate Trustee of any such property, in either case with such powers as
      may be provided in the instrument of appointment, and to vest in such
      person or persons in such capacity any property, title, right or power
      deemed necessary or desirable, subject to the provisions of the applicable
      restated trust agreement.

                                       24
<PAGE>

      SECTION 5.2. Delaware Trustee. If required by the Statutory Trust Act, one
Trustee (the "Delaware Trustee") shall be:

            (a)   a natural person who is a resident of the State of Delaware;
      or

            (b)   if not a natural person, an entity which has its principal
      place of business in the State of Delaware, and otherwise meets the
      requirements of applicable law, provided that, if the Property Trustee has
      its principal place of business in the State of Delaware and otherwise
      meets the requirements of applicable law, then the Property Trustee shall
      also be the Delaware Trustee and Section 3.11 shall have no application.

            (c)   The initial Delaware Trustee shall be:

                  The Bank of New York (Delaware)
                  502 White Clay Center
                  Route 273
                  PO Box 6973
                  Newark, Delaware 19711
                  Attention: Corporate Trust Administration

      SECTION 5.3. Property Trustee; Eligibility.

            (a)   There shall at all times be one Trustee which shall act as
      Property Trustee and which shall:

                  (i)   not be an Affiliate of the Sponsor; and

                  (ii)  be a corporation organized and doing business under the
         laws of the United States of America or any State or Territory thereof
         or of the District of Columbia, or a corporation or Person permitted by
         the Commission to act as an institutional trustee under the Trust
         Indenture Act, authorized under such laws to exercise corporate trust
         powers, having a combined capital and surplus of at least 50 million
         U.S. dollars ($50,000,000), and subject to supervision or examination
         by Federal, State, Territorial or District of Columbia authority. If
         such corporation publishes reports of condition at least annually,
         pursuant to law or to the requirements of the supervising or examining
         authority referred to above, then for the purposes of this Section
         5.3(a)(ii), 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.

            (b)   If at any time the Property Trustee shall cease to be eligible
      to so act under Section 5.3(a), the Property Trustee shall immediately
      resign in the manner and with the effect set forth in Section 5.6(c).

            (c)   If the Property Trustee has or shall acquire any "conflicting
      interest" within the meaning of Section 310(b) of the Trust Indenture Act,
      the Property Trustee and the Holder of the Common Securities (as if it
      were the obligor referred to in Section

                                       25
<PAGE>

      310(b) of the Trust Indenture Act) shall in all respects comply with the
      provisions of Section 310(b) of the Trust Indenture Act.

            (d)   The Preferred Securities Guarantee shall be deemed to be
      specifically described in this Agreement for purposes of clause (i) of the
      first provision contained in Section 310(b) of the Trust Indenture Act.

            (e)   The initial Property Trustee shall be:

                  The Bank of New York
                  101 Barclay Street, 8W
                  New York, New York 10286
                  Attention: Corporate Trust Administration

      SECTION 5.4. Certain Qualifications of Administrative Trustees and
Delaware Trustee Generally. Each Administrative Trustee and the Delaware Trustee
(unless the Property Trustee also acts as Delaware Trustee) shall be either a
natural person who is at least 21 years of age or a legal entity that shall act
through one or more Authorized Officers.

      SECTION 5.5. Administrative Trustees. The initial Administrative Trustees
shall be:

                  Ira S. Lederman
                  c/o W. R. Berkley Corporation
                  475 Steamboat Road
                  Greenwich, Connecticut 06830

                  Eugene G. Ballard
                  c/o W. R. Berkley Corporation
                  475 Steamboat Road
                  Greenwich, Connecticut 06830

            (a)   Except as expressly set forth in this Agreement and except if
      a meeting of the Administrative Trustees is called with respect to any
      matter over which the Administrative Trustees have power to act, any power
      of the Administrative Trustees may be exercised by, or with the consent
      of, any one such Administrative Trustee.

            (b)   As more specifically provided in Section 5.10, an
      Administrative Trustee may, by power of attorney consistent with
      applicable law, delegate to any other natural person over the age of 21
      his or her power for the purposes of signing any documents which the
      Administrative Trustees have power and authority to cause the Trust to
      execute pursuant to Section 3.6.

      SECTION 5.6. Appointment, Removal and Resignation of Trustees.

            (a)   Subject to Section 5.6(b), Trustees may be appointed or
      removed without cause at any time:

                                       26
<PAGE>

                  (i)   until the issuance of any Securities, by written
         instrument executed by the Sponsor;

                  (ii)  after the issuance of any Securities, by vote of the
         Holders of a Majority in liquidation amount of the Common Securities
         voting as a class at a meeting of the Holders of the Common Securities,
         unless an Event of Default under the corresponding subordinated debt
         securities shall have occurred and be continuing, in which case the
         Property Trustee and the Delaware Trustee may not be so removed; and

                  (iii) after the issuance of any Securities, if an Event of
         Default under the corresponding subordinated debt securities shall have
         occurred and be continuing, the Property Trustee and the Delaware
         Trustee may be removed by the Holders of a Majority in liquidation
         amount of the outstanding Preferred Securities.

            (b)   (i) The Trustee that acts as Property Trustee shall not be
      removed in accordance with Section 5.6(a) until a Successor Property
      Trustee (a "Successor Property Trustee") has been appointed and has
      accepted such appointment by written instrument executed by such Successor
      Property Trustee and delivered to the Administrative Trustees and the
      Sponsor; and

                  (ii) the Trustee that acts as Delaware Trustee shall not be
         removed in accordance with this Section 5.6(a) until a successor
         Trustee possessing the qualifications to act as Delaware Trustee under
         Sections 5.2 and 5.4 (a "Successor Delaware Trustee") has been
         appointed and has accepted such appointment by written instrument
         executed by such Successor Delaware Trustee and delivered to the
         Administrative Trustees and the Sponsor.

            (c)   A Trustee appointed to office shall hold office until his
      successor shall have been appointed or until his death, removal or
      resignation. Any Trustee may resign from office (without need for prior or
      subsequent accounting) by an instrument in writing signed by such Trustee
      and delivered to the Sponsor and the Trust, which resignation shall take
      effect upon such delivery or upon such later date as is specified therein;
      provided, however, that:

                  (i)   No such resignation of the Trustee that acts as the
         Property Trustee shall be effective:

            (A)   until a Successor Property Trustee has been appointed and has
      accepted such appointment by instrument executed by such Successor
      Property Trustee and delivered to the Trust, the Sponsor and the resigning
      Property Trustee; or

            (B)   until the assets of the Trust have been completely liquidated
      and the proceeds thereof distributed to the holders of the Securities; and

                  (ii)  no such resignation of the Trustee that acts as the
         Delaware Trustee shall be effective until a Successor Delaware Trustee
         has been appointed and

                                       27
<PAGE>

         has accepted such appointment by instrument executed by such Successor
         Delaware Trustee and delivered to the Trust, the Sponsor and the
         resigning Delaware Trustee.

            (d)   The Holders of the Common Securities shall use their best
      efforts to promptly appoint a Successor Delaware Trustee or Successor
      Property Trustee, as the case may be, if the Property Trustee or the
      Delaware Trustee delivers an instrument of resignation in accordance with
      this Section 5.6.

            (e)   If no Successor Property Trustee or Successor Delaware Trustee
      shall have been appointed and accepted appointment as provided in this
      Section 5.6 within 60 days after delivery to the Sponsor and the Trust of
      an instrument of resignation, the resigning Property Trustee or Delaware
      Trustee, as applicable, may petition any court of competent jurisdiction
      for appointment of a Successor Property Trustee or Successor Delaware
      Trustee at the expense of the Sponsor. Such court may thereupon, after
      prescribing such notice, if any, as it may deem proper and prescribe,
      appoint a Successor Property Trustee or Successor Delaware Trustee, as the
      case may be.

            (f)   No Property Trustee or Delaware Trustee shall be liable for
      the acts or omissions to act of any Successor Property Trustee or
      Successor Delaware Trustee, as the case may be.

      SECTION 5.7. Vacancies Among Trustees. If a Trustee ceases to hold office
for any reason and the number of Trustees is not reduced pursuant to Section
5.1, or if the number of Trustees is increased pursuant to Section 5.1, a
vacancy shall occur. A resolution certifying the existence of such vacancy by
the Administrative Trustees (or, if there are more than two, a majority of the
Administrative Trustees) shall be conclusive evidence of the existence of such
vacancy. Any such vacancy shall be filled with a Trustee appointed in accordance
with Section 5.6.

      SECTION 5.8. Effect of Vacancies. The death, resignation, retirement,
removal, bankruptcy, dissolution, liquidation, incompetence or incapacity to
perform the duties of a Trustee shall not operate to annul the Trust. Whenever a
vacancy in the number of Administrative Trustees shall occur, until such vacancy
is filled by the appointment of an Administrative Trustee in accordance with
Section 5.6, the Administrative Trustees in office, regardless of their number,
shall have all the powers granted to the Administrative Trustees and shall
discharge all the duties imposed upon the Administrative Trustees by this
Agreement.

      SECTION 5.9. Meetings. If there is more than one Administrative Trustee,
meetings of the Administrative Trustees shall be held from time to time upon the
call of any Administrative Trustee. Regular meetings of the Administrative
Trustees may be held at a time and place fixed by resolution of the
Administrative Trustees. Notice of any in-person meetings of the Administrative
Trustees shall be hand delivered or otherwise delivered in writing (including by
facsimile, with a hard copy by overnight courier) not less than 48 hours before
such meeting. Notice of any telephonic meetings of the Administrative Trustees
or any committee thereof shall be hand delivered or otherwise delivered in
writing (including by facsimile, with a hard copy by overnight courier) not less
than 24 hours before such meeting. Notices shall contain a brief statement of
the time, place and anticipated purposes of the meeting.

                                       28
<PAGE>

The presence (whether in person or by telephone) of an Administrative Trustee at
a meeting shall constitute a waiver of notice of such meeting except where an
Administrative Trustee attends a meeting for the express purpose of objecting to
the transaction of any activity on the ground that the meeting has not been
lawfully called or convened. Unless provided otherwise in this Agreement, any
action of the Administrative Trustees may be taken at a meeting by vote of a
majority of the Administrative Trustees present (whether in person or by
telephone) and eligible to vote with respect to such matter, provided that a
Quorum is present, or without a meeting by the unanimous written consent of the
Administrative Trustees. In the event there is only one Administrative Trustee,
any and all action of such Administrative Trustee shall be evidenced by a
written consent of such Administrative Trustee.

      SECTION 5.10. Delegation of Power.

            (a)   Any Administrative Trustee may, by power of attorney
      consistent with applicable law, delegate to any other natural person over
      the age of 21 his or her power for the purpose of executing any documents
      contemplated in Section 3.6, including any registration statement or
      amendment thereto filed with the Commission, or making any other
      governmental filing; and

            (b)   the Administrative Trustees shall have power to delegate from
      time to time to such of their number or to officers of the Trust the doing
      of such things and the execution of such instruments either in the name of
      the Trust or the names of the Administrative Trustees or otherwise as the
      Administrative Trustees may deem expedient, to the extent such delegation
      is not prohibited by applicable law or contrary to the provisions of the
      Trust, as set forth herein.

      SECTION 5.11. Merger, Conversion, Consolidation or Succession to Business.
Any Person into which the Property Trustee or the Delaware Trustee, as the case
may be, may be merged or converted or with which either may be consolidated, or
any Person resulting from any merger, conversion or consolidation to which the
Property Trustee or the Delaware Trustee, as the case may be, shall be a party,
or any Person succeeding to all or substantially all the corporate trust
business of the Property Trustee or the Delaware Trustee, as the case may be,
shall be the successor of the Property Trustee or the Delaware Trustee, as the
case may be, hereunder, provided such Person 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.

                                   ARTICLE VI
                                  DISTRIBUTIONS

      SECTION 6.1. Distributions. Holders shall receive Distributions (as
defined herein) in accordance with the applicable terms of the relevant Holder's
Securities. Distributions shall be made on the Preferred Securities and the
Common Securities in accordance with the preferences set forth in their
respective terms. If and to the extent that the Debenture Issuer makes a payment
of interest (including Additional Interest (as defined in the Indenture)),
premium and/or principal on the Debentures held by the Property Trustee (the
amount of any such payment being a "Payment Amount"), the Property Trustee shall
and is directed, to the

                                       29
<PAGE>

extent funds are available for that purpose, to make a distribution (a
"Distribution") of such Payment Amount to Holders.

                                   ARTICLE VII
                             ISSUANCE OF SECURITIES

      SECTION 7.1. General Provisions Regarding Securities.

            (a)   The Administrative Trustees shall, on behalf of the Trust,
      issue one class of preferred securities representing undivided beneficial
      interests in the assets of the Trust having such terms as are set forth in
      Annex I (the "Preferred Securities"), and one class of common securities
      representing undivided beneficial interests in the assets of the Trust
      having such terms as are set forth in Annex I (the "Common Securities").
      The Trust shall issue no securities or other interests in the assets of
      the Trust other than the Preferred Securities and the Common Securities.

            (b)   The Certificates shall be signed on behalf of the Trust by an
      Administrative Trustee. Such signature shall be the manual signature of
      any present or any future Administrative Trustee. In case any
      Administrative Trustee of the Trust who shall have signed any of the
      Securities shall cease to be such Administrative Trustee before the
      Certificates so signed shall be delivered by the Trust, such Certificates
      nevertheless may be delivered as though the person who signed such
      Certificates had not ceased to be such Administrative Trustee; and any
      Certificate may be signed on behalf of the Trust by such persons who, at
      the actual date of execution of such Certificate, shall be the
      Administrative Trustees of the Trust, although at the date of the
      execution and delivery of the Agreement any such person was not such an
      Administrative Trustee. Certificates shall be printed, lithographed or
      engraved or may be produced in any other manner as is reasonably
      acceptable to the Administrative Trustees, as evidenced by their execution
      thereof, and may have such letters, numbers or other marks of
      identification or designation and such legends or endorsements as the
      Administrative Trustees may deem appropriate, or as may be required to
      comply with any law or with any rule or regulation of any stock exchange
      on which Securities may be listed, or to conform to usage.

            (c)   The consideration received by the Trust for the issuance of
      the Securities shall constitute a contribution to the capital of the Trust
      and shall not constitute a loan to the Trust.

            (d)   Upon issuance of the Securities as provided in this Agreement,
      the Securities so issued shall be deemed to be validly issued, fully paid
      and (subject to Section 10.1) non-assessable.

            (e)   Every Person, by virtue of having become a Holder or a
      Preferred Security Beneficial Owner in accordance with the terms of this
      Agreement, shall be deemed to have expressly assented and agreed to the
      terms of, and shall be bound by, this Agreement.

      SECTION 7.2. Paying Agent. In the event that the Preferred Securities are
not in book-entry only form, the Trust shall maintain an office or agency where
the Preferred Securities

                                       30
<PAGE>

may be presented for payment ("Paying Agent"), and any such Paying Agent shall
comply with Section 317(b) of the Trust Indenture Act. The Trust may appoint the
Paying Agent and may appoint one or more additional paying agents in such other
locations as it shall determine. The term "Paying Agent" includes any such
additional paying agent. The Trust may change any Paying Agent without prior
notice to any Holder. The Trust shall notify the Property Trustee of the name
and address of any Agent not a party to this Agreement. If the Trust fails to
appoint or maintain another entity as Paying Agent, the Property Trustee shall
act as such. The Trust or any of its Affiliates may act as Paying Agent. The
Property Trustee shall initially act as Paying Agent for the Preferred
Securities and the Common Securities.

                                  ARTICLE VIII
                              TERMINATION OF TRUST

      SECTION 8.1. Termination of Trust. (a) The Trust shall dissolve in the
earlier to occur of 55 years after the issuance of the Debentures or:

                  (i)   upon the bankruptcy of the Sponsor;

                  (ii)  upon the filing of a certificate of dissolution or its
         equivalent with respect to the Sponsor or the revocation of the
         Sponsor's charter and the expiration of 90 days after the date of
         revocation without a reinstatement thereof;

                  (iii) upon the consent of a Majority in liquidation amount of
         the Securities affected thereby voting together as a single class to
         dissolve the Trust;

                  (iv)  upon the entry of a decree of judicial dissolution of
         the Holder of the Common Securities, the Sponsor or the Trust;

                  (v)   when all of the Securities shall have been called for
         redemption and the amounts necessary for redemption thereof shall have
         been paid to the Holders, in each case in accordance with the terms of
         the Securities;

                  (vi)  at the election of the Sponsor (which is wholly within
         its sole discretion) at any time pursuant to which the Trust shall have
         been dissolved in accordance with the terms of the Securities as set
         forth in Annex I and all of the Debentures endorsed thereon shall have
         been distributed to the Holders of Securities in exchange for all of
         the Securities; or

                  (vii) before the issuance of any Securities, with the consent
         of all of the Administrative Trustees and the Sponsor.

            (b)   As soon as is practicable after the occurrence of an event
      referred to in Section 8.1(a) and upon completion of the winding-up of the
      Trust and satisfaction of all liabilities of the Trust in accordance with
      the Statutory Trust Act, the Administrative Trustees shall file a
      certificate of cancellation with the Secretary of State of the State of
      Delaware and the Trust shall terminate.

            (c)   The provisions of Article X shall survive the termination of
      the Trust.

                                       31
<PAGE>

                                   ARTICLE IX
                              TRANSFER OF INTERESTS

      SECTION 9.1. Transfer of Securities.

            (a)   Securities may only be transferred, in whole or in part, in
      accordance with the terms and conditions set forth in this Agreement and
      in the terms of the Securities. Any transfer or purported transfer of any
      Security not made in accordance with this Agreement shall be null and
      void.

            (b)   Subject to this Article IX, Preferred Securities shall be
      freely transferable.

            (c)   Subject to this Article IX, the Sponsor and any Related Party
      may only transfer Common Securities to the Sponsor or a Related Party of
      the Sponsor; provided that, any such transfer is subject to the condition
      precedent that the transferor obtain the written opinion of nationally
      recognized independent counsel experienced in such matters that such
      transfer would not cause more than an insubstantial risk that:

                  (i)   the Trust would not continue to be classified for United
         States federal income tax purposes as a grantor trust; and

                  (ii)  the Trust would be an Investment Company or the
         transferee would become an Investment Company.

      SECTION 9.2. Transfer of Certificates. The Administrative Trustees shall
provide for the registration of Certificates and of transfers of Certificates,
which will be effected without charge but only upon payment (with such indemnity
as the Administrative Trustees may require) in respect of any tax or other
government charges that may be imposed in relation to it. Upon surrender for
registration of transfer of any Certificate, the Administrative Trustees shall
cause one or more new Certificates to be issued in the name of the designated
transferee or transferees. Every Certificate surrendered for registration of
transfer shall be accompanied by a written instrument of transfer in form
satisfactory to the Administrative Trustees duly executed by the Holder or such
Holder's attorney duly authorized in writing. Each Certificate surrendered for
registration of transfer shall be canceled by the Administrative Trustees. A
transferee of a Certificate shall be entitled to the rights and subject to the
obligations of a Holder hereunder upon the receipt by such transferee of a
Certificate. By acceptance of a Certificate, each transferee shall be deemed to
have agreed to be bound by this Agreement.

      SECTION 9.3. Deemed Security Holders. The Trustees may treat the Person in
whose name any Certificate shall be registered on the books and records of the
Trust as the sole holder of such Certificate and of the Securities represented
by such Certificate for purposes of receiving Distributions and for all other
purposes whatsoever and, accordingly, shall not be bound to recognize any
equitable or other claim to or interest in such Certificate or in the Securities
represented by such Certificate on the part of any Person, whether or not the
Trust shall have actual or other notice thereof.

      SECTION 9.4. Book Entry Interests. Unless otherwise specified in the terms
of the Preferred Securities, the Preferred Securities Certificates, on original
issuance, will be issued in

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<PAGE>

the form of one or more fully registered, global Preferred Security Certificates
(each a "Global Certificate"), to be delivered to the Depositary, the initial
Clearing Agency, by, or on behalf of, the Trust. Such Global Certificate(s)
shall initially be registered on the books and records of the Trust in the name
of Cede & Co., the nominee of the Depositary, and no Preferred Security
Beneficial Owner will receive a definitive Preferred Security Certificate
representing such Preferred Security Beneficial Owner's interests in such Global
Certificate(s), except as provided in Section 9.7. Unless and until definitive,
fully registered Preferred Security Certificates (the "Definitive Preferred
Security Certificates") have been issued to the Preferred Security Beneficial
Owners pursuant to Section 9.7:

            (a)   the provisions of this Section 9.4 shall be in full force and
      effect;

            (b)   the Trust and the Trustees shall be entitled to deal with the
      Clearing Agency for all purposes of this Agreement (including the payment
      of Distributions on the Global Certificate(s) and receiving approvals,
      votes or consents hereunder) as the Holder of the Preferred Securities and
      the sole holder of the Global Certificate(s) and shall have no obligation
      to the Preferred Security Beneficial Owners;

            (c)   to the extent that the provisions of this Section 9.4 conflict
      with any other provisions of this Agreement, the provisions of this
      Section 9.4 shall control; and

            (d)   the rights of the Preferred Security Beneficial Owners shall
      be exercised only through the Clearing Agency and shall be limited to
      those established by law and agreements between such Preferred Security
      Beneficial Owners and the Clearing Agency and/or the Clearing Agency
      Participants and the Clearing Agency shall receive and transmit payments
      of Distributions on the Global Certificates to such Clearing Agency
      Participants. The Depositary will make book entry transfers among the
      Clearing Agency Participants.

      SECTION 9.5. Notices to Clearing Agency. Whenever a notice or other
communication to the Preferred Security Holders is required under this
Agreement, unless and until Definitive Preferred Security Certificates shall
have been issued to the Preferred Security Beneficial Owners pursuant to Section
9.7, the Administrative Trustees shall give all such notices and communications
specified herein to be given to the Preferred Security Holders to the Clearing
Agency, and shall have no notice obligations to the Preferred Security
Beneficial Owners.

      SECTION 9.6. Appointment of Successor Clearing Agency. If any Clearing
Agency elects to discontinue its services as securities depositary with respect
to the Preferred Securities, the Administrative Trustees may, in their sole
discretion, appoint a successor Clearing Agency with respect to such Preferred
Securities.

      SECTION 9.7. Definitive Preferred Security Certificates. If:

            (a)   a Clearing Agency elects to discontinue its services as
      securities depositary with respect to the Preferred Securities and a
      successor Clearing Agency is not appointed within 90 days after such
      discontinuance pursuant to Section 9.6;

                                       33
<PAGE>

            (b)   the Administrative Trustees elect after consultation with the
      Sponsor to terminate the book entry system through the Clearing Agency
      with respect to the Preferred Securities; or

            (c)   after the occurrence of an Event of Default under the
      corresponding subordinated debt securities, Holders of Preferred
      Securities representing at least a majority of liquidation amount of such
      Preferred Securities advise the Property Trustee in writing that the
      continuation of a book-entry system through the Depositary is no longer in
      their best interests, then:

                  (i)   Definitive Preferred Security Certificates shall be
         prepared by the Administrative Trustees on behalf of the Trust with
         respect to such Preferred Securities; and

                  (ii)  upon surrender of the Global Certificate(s) by the
         Clearing Agency, accompanied by registration instructions, the
         Administrative Trustees shall cause Definitive Preferred Security
         Certificates to be delivered to Preferred Security Beneficial Owners in
         accordance with the instructions of the Clearing Agency. Neither the
         Trustees nor the Trust shall be liable for any delay in delivery of
         such instructions and each of them may conclusively rely on and shall
         be protected in relying on, said instructions of the Clearing Agency.
         The Definitive Preferred Security Certificates shall be printed,
         lithographed or engraved or may be produced in any other manner as is
         reasonably acceptable to the Administrative Trustees, as evidenced by
         their execution thereof, and may have such letters, numbers or other
         marks of identification or designation and such legends or endorsements
         as the Administrative Trustees may deem appropriate, or as may be
         required to comply with any law or with any rule or regulation made
         pursuant thereto or with any rule or regulation of any stock exchange
         on which Preferred Securities may be listed, or to conform to usage.

      SECTION 9.8. Mutilated, Destroyed, Lost or Stolen Certificates. If:

            (a)   any mutilated Certificates should be surrendered to the
      Administrative Trustees, or if the Administrative Trustees shall receive
      evidence to their satisfaction of the destruction, loss or theft of any
      Certificate; and

            (b)   there shall be delivered to the Administrative Trustees
      security or indemnity satisfactory to them to keep each of them harmless;

then, in the absence of notice that such Certificate shall have been acquired by
a bona fide purchaser, any Administrative Trustee on behalf of the Trust shall
execute and deliver, in exchange for or in lieu of any such mutilated,
destroyed, lost or stolen Certificate, a new Certificate of like denomination.
In connection with the issuance of any new Certificate under this Section 9.8,
the Administrative Trustees may require the payment of a sum sufficient to cover
any tax or other governmental charge that may be imposed in connection
therewith. Any duplicate Certificate issued pursuant to this Section shall
constitute conclusive evidence of an

                                       34
<PAGE>

ownership interest in the relevant Securities, as if originally issued, whether
or not the lost, stolen or destroyed Certificate shall be found at any time.

                                    ARTICLE X
                           LIMITATION OF LIABILITY OF
                    HOLDERS OF SECURITIES, TRUSTEES OR OTHERS

      SECTION 10.1. Liability.

            (a)   Except as expressly set forth in this Agreement, the
      Debentures, the Preferred Securities Guarantee, the Common Securities
      Guarantee and the terms of the Securities, the Sponsor shall not be:

                  (i)   personally liable for the return of any portion of the
         capital contributions (or any return thereon) of the Holders of the
         Securities which shall be made solely from assets of the Trust; or

                  (ii)  required to pay to the Trust or to any Holder of
         Securities any deficit upon dissolution of the Trust or otherwise.

            (b)   The Holder of the Common Securities shall be liable for all of
      the debts and obligations of the Trust (other than with respect to the
      Securities) to the extent not satisfied out of the Trust's assets.

            (c)   Pursuant to Section 3803(a) of the Statutory Trust Act, the
      Holders of the Preferred Securities shall be entitled to the same
      limitation of personal liability extended to stockholders of private
      corporations for profit organized under the General Corporation Law of the
      State of Delaware.

      SECTION 10.2. Exculpation.

            (a)   No Indemnified Person shall be liable, responsible or
      accountable in damages or otherwise to the Trust or any Covered Person for
      any loss, damage or claim incurred by reason of any act performed or
      omission made by such Indemnified Person in good faith on behalf of the
      Trust and in a manner such Indemnified Person reasonably believed to be
      within the scope of the authority conferred on such Indemnified Person by
      this Agreement or by law, except that an Indemnified Person shall be
      liable for any such loss, damage or claim incurred by reason of such
      Indemnified Person's gross negligence (or ordinary negligence in the case
      of the Property Trustee) or willful misconduct with respect to such acts
      or omissions.

            (b)   An Indemnified Person shall be fully protected in conclusively
      relying in good faith upon the records of the Trust and upon such
      information, opinions, reports or statements presented to the Trust by any
      Person as to matters the Indemnified Person reasonably believes are within
      such other Person's professional or expert competence and who has been
      selected with reasonable care by or on behalf of the Trust, including
      information, opinions, reports or statements as to the value and amount of
      the assets,

                                       35
<PAGE>

      liabilities, profits, losses, or any other facts pertinent to the
      existence and amount of assets from which Distributions to Holders of
      Securities might properly be paid.

      SECTION 10.3. Fiduciary Duty.

            (a)   To the extent that, at law or in equity, an Indemnified Person
      has duties (including fiduciary duties) and liabilities relating thereto
      to the Trust or to any other Covered Person, an Indemnified Person acting
      under this Agreement shall not be liable to the Trust or to any other
      Covered Person for its good faith reliance on the provisions of this
      Agreement. The provisions of this Agreement, to the extent that they
      restrict the duties and liabilities of an Indemnified Person otherwise
      existing at law or in equity (other than the duties imposed on the
      Property Trustee under the Trust Indenture Act), are agreed by the parties
      hereto to replace such other duties and liabilities of such Indemnified
      Person.

            (b)   Unless otherwise expressly provided herein:

                  (i)   whenever a conflict of interest exists or arises between
         any Covered Persons; or

                  (ii)  whenever this Agreement or any other agreement
         contemplated herein provides that an Indemnified Person shall act in a
         manner that is, or provides terms that are, fair and reasonable to the
         Trust or any Holder of Securities,

      the Indemnified Person shall resolve such conflict of interest, take such
      action or provide such terms, considering in each case the relative
      interest of each party (including its own interest) to such conflict,
      agreement, transaction or situation and the benefits and burdens relating
      to such interests, any customary or accepted industry practices, and any
      applicable generally accepted accounting practices or principles. In the
      absence of bad faith by the Indemnified Person, the resolution, action or
      term so made, taken or provided by the Indemnified Person shall not
      constitute a breach of this Agreement or any other agreement contemplated
      herein or of any duty or obligation of the Indemnified Person at law or in
      equity or otherwise.

            (c)   Whenever in this Agreement an Indemnified Person is permitted
      or required to make a decision:

                  (i)   in its "discretion" or under a grant of similar
         authority, the Indemnified Person shall be entitled to consider such
         interests and factors as it desires, including its own interests, and
         shall have no duty or obligation to give any consideration to any
         interest of or factors affecting the Trust or any other Person; or

                  (ii)  in its "good faith" or under another express standard,
         the Indemnified Person shall act under such express standard and shall
         not be subject to any other or different standard imposed by this
         Agreement or by applicable law.

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<PAGE>

         SECTION 10.4. Indemnification.

            (a)   (i) The Sponsor shall indemnify, to the full extent permitted
      by law, any Company Indemnified Person who was or is a party or is
      threatened to be made a party to any threatened, pending or completed
      action, suit or proceeding, whether civil, criminal, administrative or
      investigative (other than an action by or in the right of the Trust) by
      reason of the fact that he is or was a Company Indemnified Person against
      expenses (including attorneys' fees), judgments, fines and amounts paid in
      settlement actually and reasonably incurred by him in connection with such
      action, suit or proceeding if he acted in good faith and in a manner he
      reasonably believed to be in or not opposed to the best interests of the
      Trust, and, with respect to any criminal action or proceeding, had no
      reasonable cause to believe his conduct was unlawful. The termination of
      any action, suit or proceeding by judgment, order, settlement, conviction,
      or upon a plea of nolo contendere or its equivalent, shall not, of itself,
      create a presumption that the Company Indemnified Person did not act in
      good faith and in a manner which he reasonably believed to be in or not
      opposed to the best interests of the Trust, and, with respect to any
      criminal action or proceeding, had reasonable cause to believe that his
      conduct was unlawful.

                  (i)   The Sponsor shall indemnify, to the full extent
         permitted by law, any Company Indemnified Person who was or is a party
         or is threatened to be made a party to any threatened, pending or
         completed action or suit by or in the right of the Trust to procure a
         judgment in its favor by reason of the fact that he is or was a Company
         Indemnified Person against expenses (including attorneys' fees)
         actually and reasonably incurred by him in connection with the defense
         or settlement of such action or suit if he acted in good faith and in a
         manner he reasonably believed to be in or not opposed to the best
         interests of the Trust and except that no such indemnification shall be
         made in respect of any claim, issue or matter as to which such Company
         Indemnified Person shall have been adjudged to be liable to the Trust
         unless and only to the extent that the Court of Chancery of Delaware or
         the court in which such action or suit was brought shall determine upon
         application that, despite the adjudication of liability but in view of
         all the circumstances of the case, such person is fairly and reasonably
         entitled to indemnity for such expenses which such Court of Chancery or
         such other court shall deem proper.

                  (ii)  To the extent that a Company Indemnified Person shall be
         successful on the merits or otherwise (including dismissal of an action
         without prejudice or the settlement of an action without admission of
         liability) in defense of any action, suit or proceeding referred to in
         paragraphs (i) and (ii) of this Section 10.4(a), or in defense of any
         claim, issue or matter therein, he shall be indemnified, to the full
         extent permitted by law, against expenses (including attorneys' fees)
         actually and reasonably incurred by him in connection therewith.

                  (iii) Any indemnification under paragraphs (i) and (ii) of
         this Section 10.4(a) (unless ordered by a court) shall be made by the
         Sponsor only as authorized in the specific case upon a determination
         that indemnification of the Company Indemnified Person is proper in the
         circumstances because he has met the applicable

                                       37
<PAGE>

         standard of conduct set forth in paragraphs (i) and (ii). Such
         determination shall be made (1) by the Administrative Trustees by a
         majority vote of a quorum consisting of such Administrative Trustees
         who were not parties to such action, suit or proceeding, (2) if such a
         quorum is not obtainable, or, even if obtainable, if a quorum of
         disinterested Administrative Trustees so directs, by independent legal
         counsel in a written opinion, or (3) by the Common Security Holder of
         the Trust.

                  (iv)  Expenses (including attorneys' fees) incurred by a
         Company Indemnified Person in defending a civil, criminal,
         administrative or investigative action, suit or proceeding referred to
         in paragraphs (i) and (ii) of this Section 10.4(a) shall be paid by the
         Sponsor in advance of the final disposition of such action, suit or
         proceeding upon receipt of an undertaking by or on behalf of such
         Company Indemnified Person to repay such amount if it shall ultimately
         be determined that he is not entitled to be indemnified by the Sponsor
         as authorized in this Section 10.4(a). Notwithstanding the foregoing,
         no advance shall be made by the Sponsor if a determination is
         reasonably and promptly made (i) by the Administrative Trustees by a
         majority vote of a quorum of disinterested Administrative Trustees,
         (ii) if such a quorum is not obtainable, or, even if obtainable, if a
         quorum of disinterested Administrative Trustees so directs, by
         independent legal counsel in a written opinion or (iii) the Common
         Security Holder of the Trust, that, based upon the facts known to the
         Administrative Trustees, counsel or the Common Security Holder at the
         time such determination is made, such Company Indemnified Person acted
         in bad faith or in a manner that such person did not believe to be in
         or not opposed to the best interests of the Trust, or, with respect to
         any criminal proceeding, that such Company Indemnified Person believed
         or had reasonable cause to believe his conduct was unlawful. In no
         event shall any advance be made in instances where the Administrative
         Trustees, independent legal counsel or Common Security Holder
         reasonably determine that such person deliberately breached his duty to
         the Trust or its Common or Preferred Security Holders.

                  (v)   The indemnification and advancement of expenses provided
         by, or granted pursuant to, the other paragraphs of this Section
         10.4(a) shall not be deemed exclusive of any other rights to which
         those seeking indemnification and advancement of expenses may be
         entitled under any agreement, vote of stockholders or disinterested
         directors of the Sponsor or Preferred Security Holders of the Trust or
         otherwise, both as to action in his official capacity and as to action
         in another capacity while holding such office. All rights to
         indemnification under this Section 10.4(a) shall be deemed to be
         provided by a contract between the Sponsor and each Company Indemnified
         Person who serves in such capacity at any time while this Section
         10.4(a) is in effect. Any repeal or modification of this Section
         10.4(a) shall not affect any rights or obligations then existing.

                  (vi)  The Sponsor or the Trust may purchase and maintain
         insurance on behalf of any person who is or was a Company Indemnified
         Person against any liability asserted against him and incurred by him
         in any such capacity, or arising out of his status as such, whether or
         not the Sponsor would have the power to indemnify him against such
         liability under the provisions of this Section 10.4(a).

                                       38
<PAGE>

                  (vii) For purposes of this Section 10.4(a), references to "the
         Trust" shall include, in addition to the resulting or surviving entity,
         any constituent entity (including any constituent of a constituent)
         absorbed in a consolidation or merger, so that any person who is or was
         a director, trustee, officer or employee of such constituent entity, or
         is or was serving at the request of such constituent entity as a
         director, trustee, officer, employee or agent of another entity, shall
         stand in the same position under the provisions of this Section 10.4(a)
         with respect to the resulting or surviving entity as he would have with
         respect to such constituent entity if its separate existence had
         continued.

                  (viii) The indemnification and advancement of expenses
         provided by, or granted pursuant to, this Section 10.4(a) shall, unless
         otherwise provided when authorized or ratified, continue as to a person
         who has ceased to be a Company Indemnified Person and shall inure to
         the benefit of the heirs, executors and administrators of such a
         person.

            (b)   The Sponsor agrees to indemnify (i) the Property Trustee, (ii)
      the Delaware Trustee, (iii) any Affiliate of the Property Trustee and the
      Delaware Trustee, and (iv) any officers, directors, shareholders, members,
      partners, employees, representatives, custodians, nominees or agents of
      the Property Trustee and the Delaware Trustee (each of the Persons in (i)
      through (iv) being referred to as a "Fiduciary Indemnified Person") for,
      and to hold each Fiduciary Indemnified Person harmless against, any loss,
      liability or expense incurred without gross negligence (or, in the case of
      the Property Trustee, pursuant to Section 3.9, negligence) or bad faith on
      its part, arising out of or in connection with the acceptance or
      administration of the trust or trusts hereunder, including the costs and
      expenses (including reasonable legal fees and expenses) of defending
      itself against or investigating any claim or liability in connection with
      the exercise or performance of any of its powers or duties hereunder. The
      obligation to indemnify as set forth in this Section 10.4(b) shall survive
      the resignation or removal of the Property Trustee or the Delaware Trustee
      and the satisfaction and discharge of this Agreement.

            (c)   The Sponsor agrees to pay the Property Trustee and the
      Delaware Trustee, from time to time, such compensation for all services
      rendered by the Property Trustee and the Delaware Trustee hereunder
      including reasonable compensation expenses and disbursements of its agents
      and counsel as may be mutually agreed upon in writing by the Sponsor and
      the Property Trustee or the Delaware Trustee, as the case may be, and,
      except as otherwise expressly provided herein, to reimburse the Property
      Trustee and the Delaware Trustee upon its or their request for all
      reasonable expenses, disbursements and advances incurred or made by the
      Property Trustee or the Delaware Trustee, as the case may be, in
      accordance with the provisions of this Agreement, except any such expense,
      disbursement or advance as may be attributable to its or their negligence
      or bad faith.

      SECTION 10.5. Outside Businesses. Any Covered Person, the Sponsor, the
Delaware Trustee and the Property Trustee may engage in or possess an interest
in other business ventures of any nature or description, independently or with
others, similar or dissimilar to the business of the Trust, and the Trust and
the Holders of Securities shall have no rights by virtue of this

                                       39
<PAGE>

Agreement in and to such independent ventures or the income or profits derived
therefrom, and the pursuit of any such venture, even if competitive with the
business of the Trust, shall not be deemed wrongful or improper. No Covered
Persons, the Sponsor, the Delaware Trustee, or the Property Trustee shall be
obligated to present any particular investment or other opportunity to the Trust
even if such opportunity is of a character that, if presented to the Trust,
could be taken by the Trust, and any Covered Person, the Sponsor, the Delaware
Trustee and the Property Trustee shall have the right to take for its own
account (individually or as a partner or fiduciary) or to recommend to others
any such particular investment or other opportunity. Any Covered Person, the
Delaware Trustee and the Property Trustee may engage or be interested in any
financial or other transaction with the Sponsor or any Affiliate of the Sponsor,
or may act as depositary for, trustee or agent for, or act on any committee or
body of holders of, securities or other obligations of the Sponsor or its
Affiliates.

                                   ARTICLE XI
                                   ACCOUNTING

      SECTION 11.1. Fiscal Year. The fiscal year ("Fiscal Year") of the Trust
shall be the calendar year, or such other year as is required by the Code.

      SECTION 11.2. Certain Accounting Matters.

            (a)   At all times during the existence of the Trust, the
      Administrative Trustees shall keep, or cause to be kept, full books of
      account, records and supporting documents, which shall reflect in
      reasonable detail, each transaction of the Trust. The books of account
      shall be maintained on the accrual method of accounting, in accordance
      with generally accepted accounting principles, consistently applied. The
      Trust shall use the accrual method of accounting for United States federal
      income tax purposes. The books of account and the records of the Trust
      shall be examined by and reported upon as of the end of each Fiscal Year
      of the Trust by a firm of independent certified public accountants
      selected by the Administrative Trustees.

            (b)   The Administrative Trustees shall cause to be duly prepared
      and delivered to each of the Holders of Securities, any annual United
      States federal income tax information statement, required by the Code,
      containing such information with regard to the Securities held by each
      Holder as is required by the Code and the Treasury Regulations. The
      Administrative Trustees shall endeavor to deliver all such statements
      within 30 days after the end of each Fiscal Year of the Trust.

            (c)   The Administrative Trustees shall cause to be duly prepared
      and filed with the appropriate taxing authority, an annual United States
      federal income tax return, on a Form 1041 or such other form required by
      United States federal income tax law, and any other annual income tax
      returns required to be filed by the Administrative Trustees on behalf of
      the Trust with any state or local taxing authority.

      SECTION 11.3. Banking. The Trust shall maintain one or more bank accounts
in the name and for the sole benefit of the Trust; provided, however, that all
payments of funds in respect of the Debentures held by the Property Trustee
shall be made directly to the Property

                                       40
<PAGE>

Trustee Account and no other funds of the Trust shall be deposited in the
Property Trustee Account. The sole signatories for such accounts shall be
designated by the Administrative Trustees; provided, however, that the Property
Trustee shall designate the signatories for the Property Trustee Account.

      SECTION 11.4. Withholding. The Trust and the Administrative Trustees shall
comply with all withholding requirements under United States federal, state and
local law. The Trust shall request, and the Holders shall provide to the Trust,
such forms or certificates as are necessary to establish an exemption from
withholding with respect to each Holder or beneficial owner, and any
representations and forms as shall reasonably be requested by the Trust to
assist it in determining the extent of, and in fulfilling, its withholding
obligations. The Administrative Trustees shall file required forms with
applicable jurisdictions and, unless an exemption from withholding is properly
established by a Holder or beneficial owner, shall remit amounts withheld with
respect to the Holder or beneficial owner to applicable jurisdictions. To the
extent that the Trust is required to withhold and pay over any amounts to any
authority with respect to Distributions or allocations to any Holder or
beneficial owner, the amount withheld shall be deemed to be a Distribution in
the amount of the withholding to the Holder or beneficial owner. In the event of
any claimed over withholding, Holders shall be limited to an action against the
applicable jurisdiction. If the amount required to be withheld was not withheld
from actual Distributions made, the Trust may reduce subsequent Distributions by
the amount of such withholding.

                                  ARTICLE XII
                             AMENDMENTS AND MEETINGS

      SECTION 12.1. Amendments.

            (a)   Except as otherwise provided in this Agreement or by any
      applicable terms of the Securities, this Agreement may only be amended by
      a written instrument approved and executed by:

                  (i)   the Sponsor and the Administrative Trustees (or, if
         there are more than two Administrative Trustees, a majority of the
         Administrative Trustees);

                  (ii)  if the amendment affects the rights, powers, duties,
         obligations or immunities of the Property Trustee, the Property
         Trustee; and

                  (iii) if the amendment affects the rights, powers, duties,
         obligations or immunities of the Delaware Trustee, the Delaware
         Trustee.

            (b)   No amendment shall be made, and any such purported amendment
      shall be void and ineffective:

                  (i)   unless, in the case of any proposed amendment, the
         Property Trustee shall have first received an Officers' Certificate
         from each of the Trust and the Sponsor that such amendment is permitted
         by, and conforms to, the terms of this Agreement (including the terms
         of the Securities);

                                       41
<PAGE>

                  (ii)  unless, in the case of any proposed amendment which
         affects the rights, powers, duties, obligations or immunities of the
         Property Trustee and/or the Delaware Trustee, as applicable, the
         Property Trustee and/or the Delaware Trustee, as applicable shall have
         also first received an opinion of counsel (who may be counsel to the
         Sponsor or the Trust) that such amendment is permitted by, and conforms
         to, the terms of this Agreement (including the terms of the
         Securities); and

                  (iii) to the extent the result of such amendment would be to:

            (A)   cause the trust to fail to continue to be classified for
      purposes of United States federal income taxation as a grantor trust;

            (B)   reduce or otherwise adversely affect the powers of the
      Property Trustee in contravention of the Trust Indenture Act;

            (C)   cause the Trust to be deemed to be an Investment Company
      required to be registered under the Investment Company Act; or

            (D)   change the amount or timing of any distribution on the Trust
      Securities or otherwise adversely affect the amount of any distribution
      required to be made in respect of the Trust Securities as of a specified
      date, or restrict the right of a holder of Trust Securities to institute
      suit for the enforcement of any such payment on or after such date without
      the consent of each holder of Trust Securities.

            (c)   At such time after the Trust has issued any Securities that
      remain outstanding, any amendment that would adversely affect the rights,
      privileges or preferences of any Holder of Securities may be effected only
      with such additional requirements as may be set forth in the terms of such
      Securities.

            (d)   Section 9.1(c), Section 10.1(c) and this Section 12.1 shall
      not be amended without the consent of all of the Holders of the
      Securities.

            (e)   Article IV shall not be amended without the consent of the
      Holders of a Majority in liquidation amount of the Common Securities.

            (f)   The rights of the holders of the Common Securities under
      Article V to increase or decrease the number of, and appoint and remove,
      Trustees shall not be amended without the consent of the Holders of a
      Majority in liquidation amount of the Common Securities.

            (g)   notwithstanding Section 12.1(c), this Agreement may be amended
      without the consent of the Holders of the Securities to:

                  (i)   cure any ambiguity;

                  (ii)  correct or supplement any provision in this Agreement
         that may be defective or inconsistent with any other provision of this
         Agreement;

                                       42
<PAGE>

                  (iii) add to the covenants, restrictions or obligations of the
         Sponsor;

                  (iv)  conform to any change in Rule 3a-5 or written change in
         interpretation or application of Rule 3a-5 by any legislative body,
         court, government agency or regulatory authority, which change does not
         have a material adverse effect on the right, preferences or privileges
         of the Holders; and

                  (v)   modify, eliminate and add to any provision of this
         Agreement to such extent as may be necessary, provided such
         modification, elimination or addition would not adversely affect the
         rights, privileges or preference of any Holder of the Securities.

      SECTION 12.2. Meetings of the Holders of Securities; Action by Written
Consent.

            (a)   Meetings of the Holders of any class of Securities may be
      called at any time by the Administrative Trustees (or as provided in the
      terms of the Securities) to consider and act on any matter on which
      Holders of such class of Securities are entitled to act under the terms of
      this Agreement, the terms of the Securities or the rules of any stock
      exchange on which the Preferred Securities are listed or admitted for
      trading. The Administrative Trustees shall call a meeting of the Holders
      of such class if directed to do so by the Holders of at least 10% in
      liquidation amount of such class of Securities. Such direction shall be
      given by delivering to the Administrative Trustees one or more calls in a
      writing stating that the signing Holders of Securities wish to call a
      meeting and indicating the general or specific purpose for which the
      meeting is to be called. Any Holders of Securities calling a meeting shall
      specify in writing the Security Certificates held by the Holders of
      Securities exercising the right to call a meeting and only those
      Securities evidenced by Securities Certificates so specified shall be
      counted for purposes of determining whether the required percentage set
      forth in the second sentence of this paragraph has been met.

            (b)   Except to the extent otherwise provided in the terms of the
      Securities, the following provisions shall apply to meetings of Holders of
      Securities:

                  (i)   notice of any such meeting shall be given to all the
         Holders of Securities having a right to vote thereat at least 7 days
         and not more than 60 days before the date of such meeting. Whenever a
         vote, consent or approval of the Holders of Securities is permitted or
         required under this Agreement or the rules of any stock exchange on
         which the Preferred Securities are listed or admitted for trading, such
         vote, consent or approval may be given at a meeting of the Holders of
         Securities. Any action that may be taken at a meeting of the Holders of
         Securities may be taken without a meeting if a consent in writing
         setting forth the action so taken is signed by the Holders of
         Securities owning not less than the minimum amount of Securities in
         liquidation amount that would be necessary to authorize or take such
         action at a meeting at which all Holders of Securities having a right
         to vote thereon were present and voting. Prompt notice of the taking of
         action without a meeting shall be given to the Holders of Securities
         entitled to vote who have not consented in writing. The Administrative
         Trustees may specify that any written ballot submitted to the Security

                                       43
<PAGE>

         Holder for the purpose of taking any action without a meeting shall be
         returned to the Trust within the time specified by the Administrative
         Trustees;

                  (ii)  each Holder of a Security may authorize any Person to
         act for it by proxy on all matters in which a Holder of Securities is
         entitled to participate, including waiving notice of any meeting, or
         voting or participating at a meeting. No proxy shall be valid after the
         expiration of 11 months from the date thereof unless otherwise provided
         in the proxy. Every proxy shall be revocable at the pleasure of the
         Holder of Securities executing it. Except as otherwise provided herein,
         all matters relating to the giving, voting or validity of proxies shall
         be governed by the General Corporation Law of the State of Delaware
         relating to proxies, and judicial interpretations thereunder, as if the
         Trust were a Delaware corporation and the Holders of the Securities
         were stockholders of a Delaware corporation;

                  (iii) each meeting of the Holders of the Securities shall be
         conducted by the Administrative Trustees or by such other Person that
         the Administrative Trustees may designate; and

                  (iv)  unless the Statutory Trust Act, this Agreement, the
         terms of the Securities, the Trust Indenture Act or the listing rules
         of any stock exchange on which the Preferred Securities are then listed
         or trading, otherwise provides, the Administrative Trustees, in their
         sole discretion, shall establish all other provisions relating to
         meetings of Holders of Securities, including notice of the time, place
         or purpose of any meeting at which any matter is to be voted on by any
         Holders of Securities, waiver of any such notice, action by consent
         without a meeting, the establishment of a record date, quorum
         requirements, voting in person or by proxy or any other matter with
         respect to the exercise of any such right to vote.

                                  ARTICLE XIII
                       REPRESENTATIONS OF PROPERTY TRUSTEE
                              AND DELAWARE TRUSTEE

      SECTION 13.1. Representations and Warranties of Property Trustee. The
Trustee that acts as initial Property Trustee represents and warrants to the
Trust and to the Sponsor at the date of this Agreement, and each Successor
Property Trustee represents and warrants to the Trust and the Sponsor at the
time of the Successor Property Trustee's acceptance of its appointment as
Property Trustee that:

            (a)   (i) in the case of the initial Property Trustee, it is a New
      York banking corporation with trust powers, duly organized, validly
      existing and in good standing under the laws of the State of New York,
      with corporate power and authority to execute and deliver, and to carry
      out and perform its obligations under the terms of, the Agreement and (ii)
      in the case of any Successor Property Trustee, it satisfies the
      requirements of Section 5.3(a) herein;

            (b)   the execution, delivery and performance by the Property
      Trustee of the Agreement has been duly authorized by all necessary
      corporate action on the part of the

                                       44
<PAGE>

      Property Trustee. The Agreement has been duly executed and delivered by
      the Property Trustee, and it constitutes a legal, valid and binding
      obligation of the Property Trustee, enforceable against it in accordance
      with its terms, subject to applicable bankruptcy, reorganization,
      moratorium, insolvency, and other similar laws affecting creditors' rights
      generally and to general principles of equity and the discretion of the
      court (regardless of whether the enforcement of such remedies is
      considered in a proceeding in equity or at law);

            (c)   the execution, delivery and performance of the Agreement by
      the Property Trustee does not conflict with or constitute a breach of the
      Articles of Organization or By-laws of the Property Trustee; and

            (d)   no consent, approval or authorization of, or registration with
      or notice to, any State or Federal banking authority is required for the
      execution, delivery or performance by the Property Trustee, of the
      Agreement.

      SECTION 13.2. Representations and Warranties of Delaware Trustee. The
Trustee that acts as initial Delaware Trustee represents and warrants to the
Trust and to the Sponsor at the date of this Agreement, and each Successor
Delaware Trustee represents and warrants to the Trust and the Sponsor at the
time of the Successor Delaware Trustee's acceptance of its appointment as
Delaware Trustee that:

            (a)   (i) in the case of the initial Delaware Trustee, it is a
      Delaware banking corporation with trust powers, duly organized, validly
      existing and in good standing under the laws of the State of Delaware,
      with corporate power and authority to execute and deliver, and to carry
      out and perform its obligations under the terms of, the Agreement and (ii)
      in the case of any Successor Delaware Trustee, it satisfies the
      requirements of Section 5.2 herein;

            (b)   the Delaware Trustee has been authorized to perform its
      obligations under the Certificate of Trust and the Agreement. The
      Agreement under Delaware law constitutes a legal, valid and binding
      obligation of the Delaware Trustee, enforceable against it in accordance
      with its terms, subject to applicable bankruptcy, reorganization,
      moratorium, insolvency, and other similar laws affecting creditors' rights
      generally and to general principles of equity and the discretion of the
      court (regardless of whether the enforcement of such remedies is
      considered in a proceeding in equity or at law);

            (c)   no consent, approval or authorization of, or registration with
      or notice to, any State or Federal banking authority governing the banking
      or trust powers of the Delaware Trustee is required for the execution,
      delivery or performance by the Delaware Trustee, of the Agreement; and

            (d)   the Delaware Trustee is a natural person who is a resident of
      the State of Delaware or, if not a natural person, an entity which has its
      principal place of business in the State of Delaware.

                                       45
<PAGE>

                                   ARTICLE XIV
                                  MISCELLANEOUS

      SECTION 14.1. Notices. All notices provided for in this Agreement shall be
in writing, duly signed by the party giving such notice, and shall be delivered,
telecopied or mailed by registered or certified mail, as follows:

            (a) if given to the Trust, in care of the Administrative Trustees at
      the Trust's mailing address set forth below (or such other address as the
      Trust may give notice of to the Holders of the Securities):

                W. R. Berkley Capital Trust II
                c/o W. R. Berkley Corporation
                475 Steamboat Road
                Greenwich, Connecticut 06830

            (b) if given to the Delaware Trustee, at the mailing address set
      forth below (or such other address as Delaware Trustee may give notice of
      to the Holders of the Securities):

                The Bank of New York (Delaware)
                502 White Clay Center
                Route 273
                PO Box 6973
                Newark, Delaware 19711
                Attention: Corporate Trust Administration

            (c) if given to the Property Trustee, at its Corporate Trust Office
      to the attention of Corporate Trust Administration (or such other address
      as the Property Trustee may give notice of to the Holders of the
      Securities):

            (d) if given to the Holder of the Common Securities, at the mailing
      address of the Sponsor set forth below (or such other address as the
      Holder of the Common Securities may give notice to the Trust):

                W. R. Berkley Corporation
                475 Steamboat Road
                Greenwich, Connecticut 06830

            (e) if given to any other Holder, at the address set forth on the
      books and records of the Trust.

      All such notices shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid except that if a notice or other document is refused delivery or
cannot be delivered because of a changed address of which no notice was given,
such notice or other document shall be deemed to have been delivered on the date
of such refusal or inability to deliver.

                                       46
<PAGE>

      SECTION 14.2. Governing Law. This Agreement and the rights of the parties
hereunder shall be governed by and interpreted in accordance with the laws of
the State of Delaware and all rights and remedies shall be governed by such laws
without regard to principles of conflict of laws, PROVIDED, HOWEVER, THAT THERE
SHALL NOT BE APPLICABLE TO THE PARTIES HEREUNDER OR THIS TRUST AGREEMENT ANY
PROVISION OF THE LAWS (COMMON OR STATUTORY) OF THE STATE OF DELAWARE PERTAINING
TO TRUSTS THAT RELATE TO OR REGULATE, IN A MANNER INCONSISTENT WITH THE TERMS
HEREOF, (A) THE FILING WITH ANY COURT OR GOVERNMENTAL BODY OR AGENCY OF TRUSTEE
ACCOUNTS OR SCHEDULES OF TRUSTEE FEES AND CHARGES, (B) AFFIRMATIVE REQUIREMENTS
TO POST BONDS FOR TRUSTEES, OFFICERS, AGENTS OR EMPLOYEES OF A TRUST, (C) THE
NECESSITY FOR OBTAINING COURT OR OTHER GOVERNMENTAL APPROVAL CONCERNING THE
ACQUISITION, HOLDING OR DISPOSITION OF REAL OR PERSONAL PROPERTY, (D) FEES OR
OTHER SUMS PAYABLE TO TRUSTEES, OFFICERS, AGENTS OR EMPLOYEES OF A TRUST, (E)
THE ALLOCATION OF RECEIPTS AND EXPENDITURES TO INCOME OR PRINCIPAL, (F)
RESTRICTIONS OR LIMITATIONS ON THE PERMISSIBLE NATURE, AMOUNT OR CONCENTRATION
OF TRUST INVESTMENTS OR REQUIREMENTS RELATING TO THE TITLING, STORAGE OR OTHER
MANNER OF HOLDING OR INVESTING TRUST ASSETS OR (G) THE ESTABLISHMENT OF
FIDUCIARY OR OTHER STANDARDS OF RESPONSIBILITY OR LIMITATIONS ON THE ACTS OR
POWERS OF TRUSTEES THAT ARE INCONSISTENT WITH THE LIMITATIONS OR AUTHORITIES AND
POWERS OF THE TRUSTEES HEREUNDER AS SET FORTH OR REFERENCED IN THIS AGREEMENT.
SECTION 3540 OF TITLE 12 OF THE DELAWARE CODE SHALL NOT APPLY TO THE TRUST.

      SECTION 14.3. Intention of the Parties. It is the intention of the parties
hereto that the Trust be classified for United States federal income tax
purposes as a grantor trust. The provisions of this Agreement shall be
interpreted to further this intention of the parties.

      SECTION 14.4. Headings. Headings contained in this Agreement are inserted
for convenience of reference only and do not affect the interpretation of this
Agreement or any provision hereof.

      SECTION 14.5. Successors and Assigns. Whenever in this Agreement any of
the parties hereto is named or referred to, the successors and assigns of such
party shall be deemed to be included, and all covenants and agreements in this
Agreement by the Sponsor and the Trustees shall bind and inure to the benefit of
their respective successors and assigns, whether or not so expressed.

      SECTION 14.6. Partial Enforceability. If any provision of this Agreement,
or the application of such provision to any Person or circumstance, shall be
held invalid, the remainder of this Agreement, or the application of such
provision to persons or circumstances other than those to which it is held
invalid, shall not be affected thereby.

      SECTION 14.7. Counterparts. This Agreement may contain more than one
counterpart of the signature page and this Agreement may be executed by the
affixing of the signature of each of the Trustees to one of such counterpart
signature pages. All of such counterpart

                                       47
<PAGE>

signature pages shall be read as though one, and they shall have the same force
and effect as though all of the signers had signed a single signature page.

                                       48
<PAGE>

      IN WITNESS WHEREOF, the undersigned has caused these presents to be
executed as of the day and year first above written.

                              /s/ Ira S. Lederman
                              --------------------------------------------------
                              IRA S. LEDERMAN
                              Solely in his capacity as Administrative Trustee

                              /s/ Eugene G. Ballard
                              --------------------------------------------------
                              EUGENE G. BALLARD
                              Solely in his capacity as Administrative Trustee

                              THE BANK OF NEW YORK
                              as Property Trustee

                              By:/s/ Stacey B. Poindexter
                                 -----------------------------------------------
                              Name: Stacey B. Poindexter
                              Title: Assistant Vice President

                              THE BANK OF NEW YORK (DELAWARE)
                              as Delaware Trustee

                              By:/s/ Kristine K. Gullo
                                 -----------------------------------------------
                              Name: Kristine K. Gullo
                              Title: Vice President

                              W. R. BERKLEY CORPORATION
                              as Sponsor

                              By:/s/ Eugene G. Ballard
                                 -----------------------------------------------
                              Name: Eugene G. Ballard
                              Title: Senior Vice President

                                       49
<PAGE>

                                                                         ANNEX I

                                    TERMS OF

                  6.750% TRUST ORIGINATED PREFERRED SECURITIES

                    6.750% TRUST ORIGINATED COMMON SECURITIES

      Pursuant to Section 7.1 of the Amended and Restated Trust Agreement, dated
as of July 26, 2005 (as amended from time to time, the "Agreement"), the
designation, rights, privileges, restrictions, preferences and other terms and
provisions of the Preferred Securities and the Common Securities are set out
below (each capitalized term used but not defined herein has the meaning set
forth in the Agreement or, if not defined in such Agreement, as defined in the
Prospectus Supplement referred to below or the Prospectus, dated December 23,
2003, which it supplements):

      1. Designation and Number. (a) Preferred Securities. 10,000,000 Preferred
Securities of the Trust with an aggregate liquidation amount with respect to the
assets of the Trust of two hundred fifty million dollars ($250,000,000) and a
liquidation amount with respect to the assets of the Trust of $25 per preferred
security, are hereby designated for the purposes of identification only as
6.750% Trust Originated Preferred Securities((SM)) (`TOPrS((SM))')" (the
"Preferred Securities"). The Preferred Security Certificates evidencing the
Preferred Securities shall be substantially in the form of Exhibit A-1 to the
Agreement, with such changes and additions thereto or deletions therefrom as may
be required by ordinary usage, custom or practice or to conform to the rules of
any stock exchange on which the Preferred Securities are listed.

      (b) Common Securities. Four Common Securities of the Trust with an
aggregate liquidation amount with respect to the assets of the Trust of one
hundred dollars ($100) and a liquidation amount with respect to the assets of
the Trust of $25 per common security, are hereby designated for the purposes of
identification only as 6.750% Trust Originated Common Securities" (the "Common
Securities"). The Common Security Certificates evidencing the Common Securities
shall be substantially in the form of Exhibit A-2 to the Agreement, with such
changes and additions thereto or deletions therefrom as may be required by
ordinary usage, custom or practice.

      2. Distributions. (a) Distributions payable on each Security will be fixed
at a rate per annum of 6.750% (the "Coupon Rate") of the stated liquidation
amount of $25 per Security, such rate being the rate of interest payable on the
Debentures to be held by the Property Trustee. Distributions in arrears for more
than three consecutive months will bear interest thereon compounded quarterly at
the Coupon Rate (to the extent permitted by applicable law). The term
"Distributions" as used herein includes such cash distributions and any such
interest payable unless otherwise stated. A Distribution is payable only to the
extent that payments are made in respect of the Debentures held by the Property
Trustee and to the extent the Property Trustee has funds available therefor. The
amount of Distributions payable for any period will be computed for any full
quarterly Distribution period on the basis of a 360-day year of twelve 30-day
months, and for any period shorter than a full quarterly Distribution period for
which Distributions are computed, Distributions will be computed on the basis of
the actual number of days elapsed per 90-day quarter.

                                       1
<PAGE>

      (b) Distributions on the Securities will be cumulative, will accrue from
July 26, 2005, and will be payable quarterly in arrears, on January 30, April
30, July 30 and October 30 of each year, commencing on October 30, 2005, except
as otherwise described below. The Debenture Issuer has the right under the
Indenture to defer payments of interest by extending the interest payment period
from time to time on the Debentures for a period not exceeding 20 consecutive
quarters (each such period, an "Extension Period"), during which Extension
Period no interest shall be due and payable on the Debentures, provided that no
Extension Period shall last beyond the date of maturity of the Debentures. As a
consequence of any such deferral, Distributions will also be deferred. Despite
any such deferral, quarterly Distributions will continue to accrue with interest
thereon (to the extent permitted by applicable law) at the Coupon Rate
compounded quarterly during any such Extension Period. Prior to the termination
of any such Extension Period, the Debenture Issuer may further extend such
Extension Period; provided that such Extension Period together with all such
previous and further extensions thereof may not exceed 20 consecutive quarters.
Upon the termination of any Extension Period, payments of accrued Distributions
will be payable to Holders as they appeared on the books and records of the
Trust on the record date immediately preceding the end of the applicable
Extension Period. Upon the termination of any Extension Period and the payment
of all amounts then due, the Sponsor may commence a new Extension Period,
subject to the above requirements.

      (c) Distributions on the Securities will be payable to the Holders thereof
as they appear on the books and records of the Trust on the relevant record
dates. While the Preferred Securities remain in book-entry only form, the
relevant record dates shall be one Business Day prior to the relevant payment
dates, which payment dates shall correspond to the interest payment dates on the
Debentures. Subject to any applicable laws and regulations and the provisions of
the Agreement, each such payment in respect of the Preferred Securities will be
made as described under the heading "Description of the Securities -- Certain
terms of the trust preferred securities -- Book-entry-only issuance -- DTC" in
the Prospectus Supplement dated July 26, 2005, of the Trust included in the
Registration Statement on Form S-3 of the Sponsor and the Trust. The relevant
record dates for the Common Securities shall be the same record dates as for the
Preferred Securities. If the Preferred Securities shall cease to be in
book-entry only form, the relevant record dates for the Preferred Securities
shall conform to the rules of any securities exchange on which the securities
are listed and, if none, shall be the January 15, April 15, July 15 and October
15, as the case may be, before the relevant payment dates, which payment dates
correspond to the interest payment dates on the Debentures. Distributions
payable on any Securities that are not punctually paid on any Distribution
payment date, as a result of the Debenture Issuer having failed to make a
payment under the Debentures, will cease to be payable to the Person in whose
name such Securities are registered on the relevant record date, and such
defaulted Distribution will instead be payable to the Person in whose name such
Securities are registered on the special record date or other specified date
determined in accordance with the Indenture. If any date on which Distributions
are payable on the Securities is not a Business Day, then payment of the
Distribution payable on such date will be made on the next succeeding day that
is a Business Day (and without any interest or other payment in respect of any
such delay) except that, if such Business Day is in the next succeeding calendar
year, such payment shall be made on the immediately preceding Business Day, in
each case with the same force and effect as if made on such date.

                                       2
<PAGE>

      (d) In the event that there is any money or other property held by or for
the Trust that is not accounted for hereunder, such property shall be
distributed Pro Rata (as defined herein) among the Holders of the Securities.

      3. Liquidation Distribution upon Dissolution. In the event of any
voluntary or involuntary dissolution, winding-up or termination of the Trust,
the Holders of the Securities on the date of such dissolution, winding-up or
termination, as the case may be, will be entitled to receive out of the assets
of the Trust available for distribution to Holders of Securities after
satisfaction of liabilities of creditors of the Trust an amount equal to the
aggregate of the stated liquidation amount of $25 per Security plus accrued and
unpaid Distributions thereon to the date of payment (such amount being the
"Liquidation Distribution"), unless, in connection with such dissolution,
winding-up or termination, Debentures in an aggregate principal amount equal to
the aggregate stated liquidation amount of such Securities, with an interest
rate equal to the Coupon Rate of, and bearing accrued and unpaid interest in an
amount equal to the accrued and unpaid Distributions on, such Securities, shall
be distributed on a Pro Rata basis to the Holders of the Securities in exchange
for such Securities.

      If, upon any such dissolution, the Liquidation Distribution can be paid
only in part because the Trust has insufficient assets available to pay in full
the aggregate Liquidation Distribution, then the amounts payable directly by the
Trust on the Securities shall be paid on a Pro Rata basis.

      4. Redemption and Distribution. (a) The Securities are subject to
redemption in accordance herewith at any time after July 26, 2010 and, in
certain circumstances, following the occurrence of a Special Event (as defined
below).

      (b) Upon the repayment of the Debentures in whole or in part, whether at
maturity or upon redemption (either at the option of the Debenture Issuer or
pursuant to a Special Event in each case as described below), the proceeds from
such repayment or payment shall be simultaneously applied to redeem Securities
having an aggregate liquidation amount equal to the aggregate principal amount
of the Debentures so repaid or redeemed at a redemption price of $25 per
Security plus an amount equal to accrued and unpaid Distributions thereon at the
date of the redemption, payable in cash (the "Redemption Price"). Holders will
be given not less than 30 nor more than 60 days' notice of any such redemption.

      (c) If fewer than all the outstanding Securities are to be so redeemed,
the Common Securities and the Preferred Securities will be redeemed Pro Rata and
the Preferred Securities to be redeemed will be redeemed as described in Section
4(h)(ii) below.

      (d) The Sponsor shall have the right at any time, upon notice to the
Administrative Trustees, to elect to terminate the Trust, and upon receipt of
such notice, the Administrative Trustees shall dissolve the Trust and, after
satisfaction of creditors of the Trust, cause Debentures held by the Property
Trustee, having an aggregate principal amount equal to the aggregate stated
liquidation amount of, with an interest rate identical to the Coupon Rate of,
and accrued and unpaid interest equal to accrued and unpaid Distributions on,
and having the same record date for payment as, the Securities, to be
distributed to the Holders of the Securities in liquidation of such

                                       3
<PAGE>

Holders' interests in the Securities within 90 days following receipt of the
Sponsor's notice of election.

      (e) If, at any time, a Tax Event or an Investment Company Event (each as
defined below, and each a "Special Event") has occurred and is continuing, the
Company shall have the right, upon not less than 30 nor more than 60 days
notice, to redeem the Securities in whole but not in part, for cash in the
amount of the Redemption Price, within 90 days following the occurrence of such
Special Event, and, following such redemption, Securities with an aggregate
liquidation amount equal to the aggregate principal amount of the Securities so
redeemed shall be redeemed by the Trust at the Redemption Price; provided,
however, that in the case of a Tax Event if at the time there is available to
the Sponsor or the Trust the opportunity to eliminate, within such 90 day
period, such Tax Event by taking some Ministerial Action, the Sponsor or the
Trust will pursue such measure in lieu of a redemption. If the Sponsor does not
elect either (i) to terminate the Trust and cause the Debentures to be
distributed to the Holders of the Preferred Securities in liquidation of such
Holders' interests in the Securities in accordance with Section 4(d) or (ii) to
redeem the Securities, the Securities shall remain outstanding and, in the event
a Special Event is continuing, Additional Sums (as defined in Section 10.9 of
the Indenture) will be payable on the Securities.

      "Tax Event" means, in respect of a Trust, the receipt by such Trust of an
Opinion of Counsel, rendered by an independent law firm experienced in such
matters, to the effect that, as a result of any amendment to, or change
(including any announced prospective change) in, the laws (or any regulations
thereunder) of the United States or any political subdivision or taxing
authority thereof or therein, or as a result of any official administrative
pronouncement or judicial decision interpreting or applying such laws or
regulations, which amendment or change is effective or which pronouncement or
decision is announced on or after July 19, 2005, there is more than an
insubstantial risk that (i) such Trust is, or will be within 90 days of the date
of such Opinion of Counsel, subject to United States Federal income tax with
respect to interest received or accrued on the corresponding series of
Securities, (ii) interest payable by the Company on the corresponding series of
Securities is not, or within 90 days of the date of such Opinion of Counsel will
not be, deductible by the Company, in whole or in part, for United States
Federal income tax purposes or (iii) such Trust is, or will be within 90 days of
the date of such Opinion of Counsel, subject to more than a de minimis amount of
other taxes, duties, assessments or other governmental charges.

      "Investment Company Event" means, in respect of a Trust, the receipt by
such Trust of an Opinion of Counsel, rendered by an independent law firm
experienced in such matters, to the effect that, as a result of the occurrence
of a change in law or regulation or a change in interpretation or application of
law or regulation by any legislative body, court, governmental agency or
regulatory authority there is more than an insubstantial risk that the Trust is
or will be considered an "investment company" under the Investment Company Act
of 1940, as amended, that is required to be registered under this law, which
change becomes effective after July 19, 2005.

      "Ministerial Action" means the filing of a form, the making of an
election, or the pursuit of some other similar reasonable measure that has no
adverse effect on the Trust, the Sponsor, the Sponsor or the Holders.

                                       4
<PAGE>

      After the date for any distribution of Debentures upon dissolution of the
Trust: (i) the Securities will no longer be deemed to be outstanding, (ii) the
Depositary or its nominee (or any successor Clearing Agency or its nominee), as
the record Holder of the Preferred Securities, will receive a registered global
certificate or certificates representing the Debentures to be delivered upon
such distribution and (iii) any certificates representing Securities, except for
certificates representing Preferred Securities held by the Depositary or its
nominee (or any successor Clearing Agency or its nominee), will be deemed to
represent beneficial interests in the Debentures having an aggregate principal
amount equal to the aggregate stated liquidation amount of, with an interest
rate identical to the distribution rate of, and accrued and unpaid interest
equal to accrued and unpaid Distributions on such Securities until such
certificates are presented to the Debenture Issuer or its agent for transfer or
reissue.

      (f) The Trust may not redeem fewer than all the outstanding Securities
unless all accrued and unpaid Distributions have been paid on all Securities for
all quarterly Distribution periods terminating on or before the date of
redemption.

      (g) If the Debentures are distributed to holders of the Securities,
pursuant to the terms of the Indenture, the Debenture Issuer will use its best
efforts to have the Debentures listed on the New York Stock Exchange or on such
other exchange as the Preferred Securities were listed immediately prior to the
distribution of the Debentures.

      (h) Redemption or Distribution Procedures.

            (i) Notice of any redemption of, or notice of distribution of
      Debentures in exchange for, the Securities (a "Redemption/Distribution
      Notice") will be given by the Trust by mail to each Holder of Securities
      to be redeemed or exchanged not fewer than 30 nor more than 60 days before
      the date fixed for redemption or exchange thereof which, in the case of a
      redemption, will be the date fixed for redemption of the Debentures. For
      purposes of the calculation of the date of redemption or exchange and the
      dates on which notices are given pursuant to this Section 4(f)(i), a
      Redemption/Distribution Notice shall be deemed to be given on the day such
      notice is first mailed by first-class mail, postage prepaid, to Holders of
      Securities. Each Redemption/Distribution Notice shall be addressed to the
      Holders of Securities at the address of each such Holder appearing in the
      books and records of the Trust. No defect in the Redemption/Distribution
      Notice or in the mailing of either thereof with respect to any Holder
      shall affect the validity of the redemption or exchange proceedings with
      respect to any other Holder.

            (ii) In the event that fewer than all the outstanding Securities are
      to be redeemed, the Securities to be redeemed shall be redeemed Pro Rata
      from each Holder of Securities, it being understood that, in respect of
      Preferred Securities registered in the name of and held of record by the
      Depositary or its nominee (or any successor Clearing Agency or its
      nominee), the distribution of the proceeds of such redemption will be made
      to each Clearing Agency Participant (or Person on whose behalf such
      nominee holds such securities) in accordance with the procedures applied
      by such agency or nominee.

                                       5
<PAGE>

            (iii) If Securities are to be redeemed and the Trust gives a
      Redemption/Distribution Notice, which notice may only be issued if the
      Debentures are redeemed as set out in this Section 4 (which notice will be
      irrevocable), then (A) while the Preferred Securities are in book-entry
      only form, with respect to the Preferred Securities, by 12:00 noon, New
      York City time, on the redemption date, provided that the Debenture Issuer
      has paid the Property Trustee a sufficient amount of cash in connection
      with the related redemption or maturity of the Debentures, the Property
      Trustee will deposit irrevocably with the Depositary or its nominee (or
      successor Clearing Agency or its nominee) funds sufficient to pay the
      applicable Redemption Price with respect to the Preferred Securities and
      will give the Depositary irrevocable instructions and authority to pay the
      Redemption Price to the Holders of the Preferred Securities, and (B) with
      respect to Preferred Securities issued in definitive form and Common
      Securities, provided that the Debenture Issuer has paid the Property
      Trustee a sufficient amount of cash in connection with the related
      redemption or maturity of the Debentures, the Property Trustee will pay
      the relevant Redemption Price to the Holders of such Securities by check
      mailed to the address of the relevant Holder appearing on the books and
      records of the Trust on the redemption date. If a Redemption/Distribution
      Notice shall have been given and funds deposited as required, if
      applicable, then immediately prior to the close of business on the date of
      such deposit, or on the redemption date, as applicable, distributions will
      cease to accrue and all rights of Holders of such Securities so called for
      redemption will cease, except the right of the Holders of such Securities
      to receive the Redemption Price, but without interest on such Redemption
      Price. Neither the Administrative Trustees nor the Trust shall be required
      to register or cause to be registered the transfer of any Securities that
      have been so called for redemption. If any date fixed for redemption of
      Securities is not a Business Day, then payment of the Redemption Price
      payable on such date will be made on the next succeeding day that is a
      Business Day (without any interest or other payment in respect of any such
      delay) except that, if such Business Day falls in the next calendar year,
      such payment will be made on the immediately preceding Business Day, in
      each case with the same force and effect as if made on such date fixed for
      redemption. If payment of the Redemption Price in respect of any
      Securities is improperly withheld or refused and not paid either by the
      Property Trustee or by the Sponsor as guarantor pursuant to the relevant
      Securities Guarantee, Distributions on such Securities will continue to
      accrue from the original redemption date to the actual date of payment, in
      which case the actual payment date will be considered the date fixed for
      redemption for purposes of calculating the Redemption Price.

            (iv) Redemption/Distribution Notices shall be sent by the
      Administrative Trustees on behalf of the Trust to (A) in respect of the
      Preferred Securities, the Depositary or its nominee (or any successor
      Clearing Agency or its nominee) if Global Certificates have been issued
      or, if Definitive Preferred Security Certificates have been issued, to the
      Holder thereof, and (B) in respect of the Common Securities to the Holder
      thereof.

            (v) Subject to the foregoing and applicable law (including, without
      limitation, United States federal securities laws), provided the acquirer
      is not the Holder of the Common Securities or the obligor under the
      Indenture, the Sponsor or any of its

                                       6
<PAGE>

      subsidiaries may at any time and from time to time purchase outstanding
      Preferred Securities by tender, in the open market or by private
      agreement.

      5. Voting Rights - Preferred Securities. (a) Except as provided under
Sections 5(b) and 7 of this Annex I and as otherwise required by law and the
Agreement, the Holders of the Preferred Securities will have no voting rights.

      (b) Subject to the requirements set forth in this paragraph, the Holders
of a Majority in liquidation amount of the Preferred Securities, voting
separately as a class may direct the time, method, and place of conducting any
proceeding for any remedy available to the Property Trustee, or exercising any
trust or power conferred upon the Property Trustee under the Agreement,
including (i) directing the time, method, place of conducting any proceeding for
any remedy available to the Debenture Trustee, or exercising any trust or power
conferred on the Debenture Trustee with respect to the Debentures, (ii) waive
any past default and its consequences that is waivable under Section 5.7 of the
Indenture, or (iii) exercise any right to rescind or annul a declaration that
the principal of all the Debentures shall be due and payable, provided, however,
that, where a consent or action under the Indenture would require the consent or
act of the Holders of a Super Majority of the Holders in principal amount of
Debentures affected thereby, the Property Trustee may only give such consent or
take such action at the written direction of the Holders of at least the
proportion in liquidation amount of the Preferred Securities which the relevant
Super Majority represents of the aggregate principal amount of the Debentures
outstanding. The Property Trustee shall not revoke any action previously
authorized or approved by a vote of the Holders of the Preferred Securities.
Other than with respect to directing the time, method and place of conducting
any remedy available to the Property Trustee or the Debenture Trustee as set
forth above, the Property Trustee shall not take any action in accordance with
the directions of the Holders of the Preferred Securities under this paragraph
unless the Property Trustee has obtained an opinion of tax counsel to the effect
that for the purposes of United States federal income tax the Trust will not be
classified as other than a grantor trust on account of such action. If an Event
of Default has occurred and is continuing and such event is attributable to the
failure of the Debenture Issuer to pay interest or principal on the Debentures
on the date such interest or principal is otherwise payable (or in the case of
redemption, on the redemption date), then a Holder of Preferred Securities may
directly institute a proceeding for enforcement of payment to such Holder of the
principal of or interest on the Debentures having a principal amount equal to
the aggregate liquidation amount of the Preferred Securities of such Holder on
or after the respective due date specified in the Debentures. Notwithstanding
any payments made to such Holder by the Debenture Issuer in connection with such
proceeding, the Debenture Issuer shall remain obligated to pay the principal of
or interest on the Debentures held by the Trust or the Property Trustee, and the
Sponsor shall be subrogated to the rights of the Holders of Preferred Securities
with respect to payments on the Preferred Securities to the extent of any
payments made by the Debenture Issuer to such Holder in any such proceeding.
Except as provided in the second preceding sentence, the Holders of Preferred
Securities will not be able to exercise directly any other remedy available to
the holders of the Debentures.

      Any approval or direction of Holders of Preferred Securities may be given
at a separate meeting of Holders of Preferred Securities convened for such
purpose, at a meeting of all of the Holders of Securities in the Trust or
pursuant to written consent. The Administrative Trustees

                                       7
<PAGE>

will cause a notice of any meeting at which Holders of Preferred Securities are
entitled to vote, or of any matter upon which action by written consent of such
Holders is to be taken, to be mailed to each Holder of record of Preferred
Securities. Each such notice will include a statement setting forth (i) the date
of such meeting or the date by which such action is to be taken, (ii) a
description of any resolution proposed for adoption at such meeting on which
such Holders are entitled to vote or of such matter upon which written consent
is sought and (iii) instructions for the delivery of proxies or consents.

      No vote or consent of the Holders of the Preferred Securities will be
required for the Trust to redeem and cancel Preferred Securities or to
distribute the Debentures in accordance with the Agreement and the terms of the
Securities.

      Notwithstanding that Holders of Preferred Securities are entitled to vote
or consent under any of the circumstances described above, any of the Preferred
Securities that are owned by the Sponsor or any Affiliate of the Sponsor shall
not be entitled to vote or consent and shall, for purposes of such vote or
consent, be treated as if they were not outstanding.

6. Voting Rights - Common Securities. (a) Except as provided under Sections 6(b)
and (c) of this Annex I and as otherwise required by law and the Agreement, the
Holders of the Common Securities will have no voting rights.

      (b) The Holders of the Common Securities are entitled, in accordance with
Article V of the Agreement, to vote to appoint, remove or replace any Trustee or
to increase or decrease the number of Trustees.

      (c) Subject to Section 2.6 of the Agreement and only after the Event of
Default with respect to the Preferred Securities has been cured, waived, or
otherwise eliminated and subject to the requirements of the second to last
sentence of this paragraph, the Holders of a Majority in liquidation amount of
the Common Securities, voting separately as a class, may direct the time,
method, and place of conducting any proceeding for any remedy available to the
Property Trustee, or exercising any trust or power conferred upon the Property
Trustee under the Agreement, including (i) directing the time, method, place of
conducting any proceeding for any remedy available to the Debenture Trustee, or
exercising any trust or power conferred on the Debenture Trustee with respect to
the Debentures, (ii) waive any past default and its consequences that is
waivable under Section 5.7 of the Indenture, or (iii) exercise any right to
rescind or annul a declaration that the principal of all the Debentures shall be
due and payable, provided that, where a consent or action under the Indenture
would require the consent or act of the Holders of a Super Majority in principal
amount of Debentures affected thereby, the Property Trustee may only give such
consent or take such action at the written direction of the Holders of at least
the proportion in liquidation amount of the Common Securities which the relevant
Super Majority represents of the aggregate principal amount of the Debentures
outstanding. Pursuant to this Section 6(c), the Property Trustee shall not
revoke any action previously authorized or approved by a vote of the Holders of
the Preferred Securities. Other than with respect to directing the time, method
and place of conducting any remedy available to the Property Trustee or the
Debenture Trustee as set forth above, the Property Trustee shall not take any
action in accordance with the directions of the Holders of the Common Securities
under this paragraph unless the Property Trustee has obtained an opinion of tax
counsel to the effect that for the

                                       8
<PAGE>

purposes of United States federal income tax the Trust will not be classified as
other than a grantor trust on account of such action.

      Any approval or direction of Holders of Common Securities may be given at
a separate meeting of Holders of Common Securities convened for such purpose, at
a meeting of all of the Holders of Securities in the Trust or pursuant to
written consent. The Administrative Trustees will cause a notice of any meeting
at which Holders of Common Securities are entitled to vote, or of any matter
upon which action by written consent of such Holders is to be taken, to be
mailed to each Holder of record of Common Securities. Each such notice will
include a statement setting forth (i) the date of such meeting or the date by
which such action is to be taken, (ii) a description of any resolution proposed
for adoption at such meeting on which such Holders are entitled to vote or of
such matter upon which written consent is sought and (iii) instructions for the
delivery of proxies or consents.

      No vote or consent of the Holders of the Common Securities will be
required for the Trust to redeem and cancel Common Securities or to distribute
the Debentures in accordance with the Agreement and the terms of the Securities.

      7. Amendments to Agreement and Indenture. (a) In addition to any
requirements under Section 12.1 of the Agreement, if any proposed amendment to
the Agreement provides for, or the Administrative Trustees otherwise propose to
effect, (i) any action that would adversely affect the powers, preferences or
special rights of the Securities, whether by way of amendment to the Agreement
or otherwise, or (ii) the dissolution, winding-up or termination of the Trust,
other than as described in Section 8.1 of the Agreement, then the Holders of
outstanding Securities as a class, will be entitled to vote on such amendment or
proposal (but not on any other amendment or proposal) and such amendment or
proposal shall not be effective except with the approval of the Holders of at
least a Majority in liquidation amount of the Securities, voting together as a
single class; provided, however, if any amendment or proposal referred to in
clause (i) above would adversely affect only the Preferred Securities or only
the Common Securities, then only the affected class will be entitled to vote on
such amendment or proposal and such amendment or proposal shall not be effective
except with the approval of a Majority in liquidation amount of such class of
Securities.

      (b) In the event the consent of the Property Trustee as the holder of the
Debentures is required under the Indenture with respect to any amendment,
modification or termination of the Indenture or the Debentures, the Property
Trustee shall request the written direction of the Holders of the Securities
with respect to such amendment, modification or termination and shall vote with
respect to such amendment, modification or termination as directed by a Majority
in liquidation amount of the Securities voting together as a single class;
provided, however, that where a consent under the Indenture would require the
consent of the holders of a Super Majority of the Debentures, the Property
Trustee may only give such consent at the direction of the Holders of at least
the proportion in liquidation amount of the Securities which the relevant Super
Majority represents of the aggregate principal amount of the Debentures
outstanding; provided, further, that the Property Trustee shall not take any
action in accordance with the directions of the Holders of the Securities under
this Section 7(b) unless the Property Trustee has obtained an opinion of tax
counsel to the effect that for the purposes of United States federal income tax
the Trust will not be classified as other than a grantor trust on account of
such action.

                                       9
<PAGE>

      8. Pro Rata. A reference in this Annex I to any payment, distribution or
treatment as being "Pro Rata" shall mean pro rata to each Holder of Securities
according to the aggregate liquidation amount of the Securities held by the
relevant Holder in relation to the aggregate liquidation amount of all
Securities outstanding unless, in relation to a payment, an Event of Default
under the Agreement has occurred and is continuing, in which case any funds
available to make such payment shall be paid first to each Holder of the
Preferred Securities pro rata according to the aggregate liquidation amount of
Preferred Securities held by the relevant Holder relative to the aggregate
liquidation amount of all Preferred Securities outstanding, and only after
satisfaction of all amounts owed to the Holders of the Preferred Securities, to
each Holder of Common Securities pro rata according to the aggregate liquidation
amount of Common Securities held by the relevant Holder relative to the
aggregate liquidation amount of all Common Securities outstanding.

      9. Ranking. The Preferred Securities rank pari passu with, and payment
thereon shall be made Pro Rata with, the Common Securities except that, where an
Event of Default occurs and is continuing under the Indenture in respect of the
Debentures held by the Property Trustee, the rights of Holders of the Common
Securities to payment in respect of Distributions and payments upon liquidation,
redemption and otherwise are subordinated to the rights to payment of the
Holders of the Preferred Securities.

      10. Listing. The Administrative Trustees shall use their best efforts to
cause the Preferred Securities to be listed for quotation on the New York Stock
Exchange, Inc.

      11. Acceptance of Securities Guarantee and Indenture. Each Holder of
Preferred Securities and Common Securities, by the acceptance thereof, agrees to
the provisions of the Preferred Securities Guarantee and the Common Securities
Guarantee, respectively, including the subordination provisions therein, and to
the provisions of the Indenture.

      12. No Preemptive Rights. The Holders of the Securities shall have no
preemptive rights to subscribe for any additional securities.

      13. Miscellaneous. The foregoing terms set forth in this Annex I
constitute a part of the Agreement.

      The Sponsor will provide a copy of the Agreement, the Preferred Securities
Guarantee or the Common Securities Guarantee (as may be appropriate), and the
Indenture to any Holder without charge on written request to the Sponsor at its
principal place of business.

                                       10
<PAGE>

                                   EXHIBIT A-1

                     FORM OF PREFERRED SECURITY CERTIFICATE

      [IF THE PREFERRED SECURITY IS TO BE A GLOBAL CERTIFICATE INSERT - This
Preferred Security is a Global Certificate within the meaning of the Agreement
hereinafter referred to and is registered in the name of The Depository Trust
Company, a New York corporation (the "Depositary"), or a nominee of the
Depositary. This Preferred Security is exchangeable for Preferred Securities
registered in the name of a person other than the Depositary or its nominee only
in the limited circumstances described in the Agreement and no transfer of this
Preferred Security (other than a transfer of this Preferred Security as a whole
by the Depositary to a nominee of the Depositary or by a nominee of the
Depositary to the Depositary or another nominee of the Depositary) may be
registered except in limited circumstances.

      Unless this Preferred Security is presented by an authorized
representative of the Depositary to the Trust or its agent for registration of
transfer, exchange or payment, and any Preferred Security issued is registered
in the name of Cede & Co. or such other name as requested by an authorized
representative of the Depositary (and any payment hereon is made to Cede & Co.),
ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY
PERSON IS WRONGFUL in as much as the registered owner hereof, Cede & Co., has an
interest herein.]

Certificate Number:

Number of Preferred Securities:

                                                          CUSIP No.: 08449Q 20 3

                   Certificate Evidencing Preferred Securities
                                       of

                         W. R. BERKLEY CAPITAL TRUST II

         6.750% Trust Originated Preferred Securities(SM) ("TOPrS"(SM))
                 (liquidation amount $25 per Preferred Security)

      W. R. BERKLEY CAPITAL TRUST II, a statutory trust formed under the laws of
the State of Delaware (the "Trust"), hereby certifies that            (the
"Holder") is the registered owner of preferred securities of the Trust
representing undivided beneficial interests in the assets of the Trust
designated the 6.750% Trust Originated Preferred Securities(SM) (liquidation
amount $25 per Preferred Security) (the "Preferred Securities"). The Preferred
Securities are transferable on the books and records of the Trust, in person or
by a duly authorized attorney, upon surrender of this certificate duly endorsed
and in proper form for transfer. The designation, rights, privileges,
restrictions, preferences and other terms and provisions of the Preferred
Securities represented hereby are issued and shall in all respects be subject to
the provisions of the Amended and Restated Trust Agreement of the Trust dated as
of July 26, 2005, as the same may be amended from time to time (the
"Agreement"), including the

                                      A-1-1
<PAGE>

designation of the terms of the Preferred Securities as set forth in Annex I to
the Agreement. Capitalized terms used herein but not defined shall have the
meaning given them in the Agreement. The Holder is entitled to the benefits of
the Preferred Securities Guarantee to the extent provided therein. The Sponsor
will provide a copy of the Agreement, the Preferred Securities Guarantee and the
Indenture to the Holder without charge upon written request to the Trust at its
principal place of business.

      Upon receipt of this certificate, the Holder is bound by the Agreement and
is entitled to the benefits thereunder.

      By acceptance, the Holder agrees to treat, for United States federal
income tax purposes, the Debentures as indebtedness and the Preferred Securities
as evidence of indirect beneficial ownership in the Debentures.

      Distributions payable on each Preferred Security will be fixed at a rate
per annum of 6.750% (the "Coupon Rate") of the stated liquidation amount of $25
per Preferred Security, such rate being the rate of interest payable on the
Debentures to be held by the Property Trustee. Distributions in arrears for more
than one quarter will bear interest thereon compounded quarterly at the Coupon
Rate (to the extent permitted by applicable law). The term "Distributions" as
used herein includes such cash distributions and any such interest payable
unless otherwise stated. A Distribution is payable only to the extent that
payments are made in respect of the Debentures held by the Property Trustee and
to the extent the Property Trustee has funds available therefor. The amount of
Distributions payable for any period will be computed for any full quarterly
Distribution period on the basis of a 360-day year of twelve 30-day months, and
for any period shorter than a full quarterly Distribution period for which
Distributions are computed, Distributions will be computed on the basis of the
actual number of days elapsed per 90-day quarter.

      Except as otherwise described below, Distributions on the Preferred
Securities will be cumulative, will accrue from the date of original issuance
and will be payable quarterly in arrears, on January 30, April 30, July 30 and
October 30 of each year, commencing on October 30, 2005, to Holders of record
one (1) Business Day prior to such payment dates, which payment dates shall
correspond to the interest payment dates on the Debentures; provided however,
that if the Preferred Securities are not then in book-entry only form, such
Distributions shall be paid to the Holders of record on the January 15, April
15, July 15 and October 15, as the case may be, prior to such payment dates. The
Debenture Issuer has the right under the Indenture to defer payments of interest
by extending the interest payment period from time to time on the Debentures for
a period not exceeding 20 consecutive quarters (each an "Extension Period") and,
as a consequence of such deferral, Distributions will also be deferred. Despite
such deferral, quarterly Distributions will continue to accrue with interest
thereon (to the extent permitted by applicable law) at the Coupon Rate
compounded quarterly during any such Extension Period. Prior to the termination
of any such Extension Period, the Debenture Issuer may further extend such
Extension Period; provided that such Extension Period together with all such
previous and further extensions thereof may not exceed 20 consecutive quarters.
Payments of accrued Distributions will be payable to Holders as they appear on
the books and records of the Trust on the record date immediately preceding the
end of the Extension Period. Upon the termination of

                                     A-1-2
<PAGE>

any Extension Period and the payment of all amounts then due, the Debenture
Issuer may commence a new Extension Period, subject to the above requirements.

      The Preferred Securities shall be redeemable as provided in the Agreement.

                                     A-1-3
<PAGE>

      IN WITNESS WHEREOF, the Trust has executed this certificate this ____ day
of ___, ____.

W. R. BERKLEY CAPITAL TRUST II

_____________________________________
By:
Name:
Title: Administrative Trustee

                                     A-1-4
<PAGE>

                                   ASSIGNMENT

FOR VALUE RECEIVED, the undersigned assigns and transfers this Preferred
Security Certificate to:

        (Insert assignee's social security or tax identification number)
                   (Insert address and zip code of assignee)

and irrevocably appoints

                        agent to transfer this Preferred Security Certificate on
the books of the Trust. The agent may substitute another to act for him or her.

Date:

Signature:

(Sign exactly as your name appears on the other side of this Preferred Security
Certificate)

                                     A-1-5
<PAGE>

                                   EXHIBIT A-2

                       FORM OF COMMON SECURITY CERTIFICATE

      The Common Securities may only be transferred by the Sponsor and any
Related Party to the Sponsor or a Related Party of the Sponsor; provided that,
any such transfer is subject to the condition precedent that the transferor
obtain the written opinion of nationally recognized independent counsel
experienced in such matters that such transfer would not cause more than an
insubstantial risk that:

            (i) the Trust would not be classified for United States federal
      income tax purposes as a grantor Trust; and

            (ii) the Trust would be an Investment Company or the transferee
      would become an Investment Company.

Certificate Number:

Number of Common Securities:

                    Certificate Evidencing Common Securities

                         W. R. BERKLEY CAPITAL TRUST II

                    6.750% Trust Originated Common Securities
                  (liquidation amount $25 per Common Security)

      W. R. BERKLEY CAPITAL TRUST II, a statutory trust formed under the laws of
the State of Delaware (the "Trust"), hereby certifies that (the "Holder") is the
registered owner of common securities of the Trust representing undivided
beneficial interests in the assets of the Trust designated the 6.750% Trust
Originated Common Securities (liquidation amount $25 per Common Security) (the
"Common Securities"). The Common Securities are transferable on the books and
records of the Trust, in person or by a duly authorized attorney, upon surrender
of this certificate duly endorsed and in proper form for transfer. The
designation, rights, privileges, restrictions, preferences and other terms and
provisions of the Common Securities represented hereby are issued and shall in
all respects be subject to the provisions of the Amended and Restated Trust
Agreement of the Trust dated as of July 26, 2005, as the same may be amended
from time to time (the "Agreement"), including the designation of the terms of
the Common Securities as set forth in Annex I to the Agreement. Capitalized
terms used herein but not defined shall have the meaning given them in the
Agreement. The Holder is entitled to the benefits of the Common Securities
Guarantee to the extent provided therein. The Sponsor will provide a copy of the
Agreement, the Common Securities Guarantee and the Indenture to a Holder without
charge upon written request to the Sponsor at its principal place of business.

      Upon receipt of this certificate, the Sponsor is bound by the Agreement
and is entitled to the benefits thereunder.

                                     A-2-1
<PAGE>

      By acceptance, the Holder agrees to treat, for United States federal
income tax purposes, the Debentures as indebtedness and the Common Securities as
evidence of indirect beneficial ownership in the Debentures.

      Distributions payable on each Common Security will be fixed at a rate per
annum of 6.750% (the "Coupon Rate") of the stated liquidation amount of $25 per
Common Security, such rate being the rate of interest payable on the Debentures
to be held by the Property Trustee. Distributions in arrears for more than one
quarter will bear interest thereon compounded quarterly at the Coupon Rate (to
the extent permitted by applicable law). The term "Distributions" as used herein
includes such cash distributions and any such interest payable unless otherwise
stated. A Distribution is payable only to the extent that payments are made in
respect of the Debentures held by the Property Trustee and to the extent the
Property Trustee has funds available therefor. The amount of Distributions
payable for any period will be computed for any full quarterly Distribution
period on the basis of a 360-day year of twelve 30-day months, and for any
period shorter than a full quarterly Distribution period for which Distributions
are computed, Distributions will be computed on the basis of the actual number
of days elapsed per 90-day quarter.

      Except as otherwise described below, Distributions on the Common
Securities will be cumulative, will accrue from the date of original issuance
and will be payable quarterly in arrears, on January 30, April 30, July 30 and
October 30 of each year, commencing on October 30, 2005, to Holders of record
one (1) Business Day prior to such payment dates, which payment dates shall
correspond to the interest payment dates on the Debentures; provided, however,
that if the Preferred Securities are not then in book-entry only form, such
Distributions shall be paid to the Holders of record on the January 15, April
15, July 15 and October 15, as the case may be, prior to such payment dates. The
Debenture Issuer has the right under the Indenture to defer payments of interest
by extending the interest payment period from time to time on the Debentures for
a period not exceeding 20 consecutive quarters (each an "Extension Period") and,
as a consequence of such deferral, Distributions will also be deferred. Despite
such deferral, quarterly Distributions will continue to accrue with interest
thereon (to the extent permitted by applicable law) at the Coupon Rate
compounded quarterly during any such Extension Period. Prior to the termination
of any such Extension Period, the Debenture Issuer may further extend such
Extension Period; provided that such Extension Period together with all such
previous and further extensions thereof may not exceed 20 consecutive quarters.
Payments of accrued Distributions will be payable to Holders as they appear on
the books and records of the Trust on the record date immediately preceding the
end of the Extension Period. Upon the termination of any Extension Period and
the payment of all amounts then due, the Debenture Issuer may commence a new
Extension Period, subject to the above requirements.

      The Common Securities shall be redeemable as provided in the Agreement.

                                     A-2-2
<PAGE>

      IN WITNESS WHEREOF, the Trust has executed this certificate this ____ day
of ____, ____.

W. R. BERKLEY CAPITAL TRUST II

By:__________________________________
Name:
Title: Administrative Trustee

                                     A-2-3
<PAGE>

                                   ASSIGNMENT

      FOR VALUE RECEIVED, the undersigned assigns and transfers this Common
Security Certificate to:

        (Insert assignee's social security or tax identification number)
                    (Insert address and zip code of assignee)

and irrevocably appoints

                                    agent to transfer this Common Security
Certificate on the books of the Trust. The agent may substitute another to act
for him or her.

Date:

Signature:

(Sign exactly as your name appears on the other side of this Common Security
Certificate)

                                     A-2-4
<PAGE>

                                   EXHIBIT B

                             SPECIMEN OF DEBENTURE

                     FORM OF FACE OF SUBORDINATED DEBENTURE

      THIS SUBORDINATED DEBENTURE IS REGISTERED IN THE NAME OF THE BANK OF NEW
YORK, AS PROPERTY TRUSTEE, AND MAY NOT BE TRANSFERRED, SOLD OR OTHERWISE
DISPOSED OF OTHER THAN AS PERMITTED IN THE SUPPLEMENTAL INDENTURE DATED AS OF
July 26, 2005, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY.

      This Subordinated Debenture is Global Security within the meaning of the
Indenture hereinafter referred to and is registered in the name of the
Depositary or a nominee of the Depositary. This Subordinated Debenture is
exchangeable for Subordinated Debentures registered in the name of a person
other than the Depositary or its nominee only in the limited circumstances
described in the Indenture, and no transfer of this Subordinated Debenture
(other than a transfer of this Subordinated Debenture as a whole by the
Depositary to a nominee of the Depositary or by a nominee of the Depositary to
the Depositary or another nominee of the Depositary) may be registered except in
limited circumstances.

      Unless this Subordinated Debenture is presented by an authorized
representative of The Depository Trust Company (55 Water Street, New York, New
York) to the issuer or its agent for registration of transfer, exchange or
payment, and any Subordinated Debenture issued is registered in the name of Cede
& Co. or such other name as requested by an authorized representative of The
Depository Trust Company and any payment hereon is made to Cede & Co., ANY
TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS
WRONGFUL since the registered owner hereof, Cede & Co., has an interest herein.

                            W. R. BERKLEY CORPORATION

CUSIP No.: 084423 AN 2

                6.750% Subordinated Debentures Due July 26, 2045

No.                                                                  $__________

      W. R. BERKLEY CORPORATION, a corporation duly organized and existing under
the laws of the State of Delaware (herein called the "Company", which term
includes any successor corporation under the Indenture (as defined on the
reverse hereof)), for value received, hereby promises to pay to___________, the
principal sum of $____________ Dollars on July 26, 2045 (such date is
hereinafter referred to as the "Stated Maturity") and to pay interest thereon
from July 26, 2005. Interest shall be payable on this Subordinated Debenture, in
arrears, on January 30, April 30, July 30 and October 30 of each year (each an
"Interest Payment Date") commencing October 30, 2005, at the rate of 6.750% per
annum, until the principal hereof is paid or made available for payment;
provided that any such installment of interest which is overdue shall bear
interest at the rate of 6.750% per annum (to the extent that the payment of

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such interest shall be legally enforceable) from the dates such amounts are due
until they are paid or made available for payment, and such interest shall be
payable on demand; provided further that, notwithstanding anything contained in
the Indenture (as defined on the reverse hereof) to the contrary, the Company
shall have the right at any time, and from time to time, during the term of this
Subordinated Debenture to defer payments of interest by extending the interest
payment period to the next Interest Payment Date by one or more quarterly
periods not exceeding 20 consecutive quarters (each such period, an "Extension
Period"), but no such Extension Period may extend beyond July 26, 2045, or such
other date to which the Stated Maturity may have been shortened or extended as
described below. At the end of any such Extension Period, the Company shall pay
all interest then accrued and unpaid (including any Additional Sums, as defined
in Section 10.9 of the Indenture), together with interest thereon compounded
quarterly at the rate specified for this Subordinated Debenture to the extent
permitted by applicable law; provided, that during any such Extension Period,
(a) the Company shall not declare or pay dividends on, make any distribution
with respect to, or redeem, purchase, acquire or make a liquidation payment with
respect to any of its Capital Stock (other than (i) purchases or acquisitions of
shares of the Company's Common Stock in connection with the satisfaction by the
Company of its obligations under any employee benefit plans or the satisfaction
by the Company of its obligation pursuant to any contract or security requiring
it to purchase shares of its Common Stock, (ii) as a result of a
reclassification of the Company's Capital Stock or the exchange or conversion of
one class or series of the Company's Capital Stock for another class or series
of its Capital Stock, (iii) the purchase of fractional interests in shares of
the Company's Capital Stock pursuant to an acquisition or the conversion or
exchange provisions of such Capital Stock or the security being converted or
exchanged, and (iv) redemptions or purchases pursuant to the Company's Rights
Agreement, dated as of May 11, 1999, as amended, between the Company and Wells
Fargo Bank Minnesota, N.A., as successor in interest to ChaseMellon Shareholder
Services, LLC), (b) the Company shall not make any payment of principal,
premium, if any, or interest on or repay, repurchase or redeem any debt
securities issued by the Company that rank pari passu with or junior to this
Subordinated Debenture and (c) the Company shall not make any guarantee payments
with respect to the foregoing (other than pursuant to the Preferred Securities
Guarantee Agreement, dated as of July 26, 2005 of the Company (the "Guarantee")
with respect to the 6.750% Trust Originated Preferred Securities (the "Preferred
Securities") issued by W. R. Berkley Capital Trust II (the "Trust"), and the
Common Securities Guarantee Agreement, dated as of July 26, 2005 of the Company
(the "Common Guarantee"), the Common Securities Guarantee Agreement, dated as of
December 20, 1996 and the Capital Securities Guarantee Agreement, dated as of
June 6, 1997 with respect to the 8.197% Capital Securities). Prior to the
termination of any such Extension Period, the Company may further defer payments
of interest by extending the interest payment period; provided, however, that,
such Extension Period, including all such previous and further extensions, may
not exceed 20 consecutive quarters or extend beyond the Stated Maturity. Upon
the termination of any Extension Period and the payment of all amounts then due,
the Company may commence a new Extension Period, subject to the terms set forth
below. No interest shall be due and payable during any Extension Period, except
at the end thereof, but the Company may prepay at any time all or any portion of
the interest accrued during any Extension Period. If the Property Trustee (as
defined in the Amended and Restated Trust Agreement of the Trust (the "Trust
Agreement") shall be the sole holder of this Subordinated Debenture, Company
shall give the Administrative Trustees (as

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defined in the Trust Agreement) and the Property Trustee (as defined in the
Trust Agreement), notice of its selection of such Extension Period one Business
Day prior to the earlier of (i) the date Distributions on the Preferred
Securities are payable or (ii) the date the Administrative Trustees are required
to give notice of the record date or the date such distribution is payable to
the New York Stock Exchange (or other applicable self-regulatory organization)
or to holders of the Preferred Securities, but in any event at least one
Business Day before such record date. If the Property Trustee shall not be the
sole holder of this Subordinated Debenture, the Company shall give the holders
of this Subordinated Debenture notice of its selection of such Extension Period
at least 10 Business Days prior to the earlier of (i) the Interest Payment Date
or (ii) the date upon which the Company is required to give notice of the record
or payment date of such interest payment to the New York Stock Exchange (or
other applicable self-regulatory organization) or to holders of this
Subordinated Debenture. The quarter in which any notice is given in accordance
with the foregoing provisions shall be counted as one of the 20 quarters
permitted in the maximum Extension Period permitted hereunder.

      The amount of interest payable on any Interest Payment Date shall be
computed on the basis of twelve 30-day months and a 360-day year and, for any
period that is shorter than a full 90-day quarter, will be calculated on the
basis of the actual number of days elapsed in such period. In the event that any
date on which interest is payable on this Subordinated Debenture is not a
Business Day, then payment of the interest payable on such date will be made on
the next succeeding day which is a Business Day (and without any interest or
other payment in respect of any such delay), except that, if such Business Day
is in the next succeeding calendar year, such payment shall be made on the
immediately preceding Business Day, in each case with the same force and effect
as if made on such date. The interest so payable on any Interest Payment Date
which is punctually paid or duly provided for on any Interest Payment Date will,
as provided in the Indenture referred to on the reverse hereof, be paid to the
person in whose name this Subordinated Debenture is registered at the close of
business on the Regular Record Date for such Interest Payment Date, which shall
be the Business Day preceding such Interest Payment Date; provided, that in the
event the Securities shall not continue to remain in book-entry only form, the
record dates shall be the January 15, April 15, July 15 and October 15 prior to
the applicable Interest Payment Date. Any such interest not so punctually paid
or duly provided for will forthwith cease to be payable to the Person in whose
name this Subordinated Debenture is registered on the relevant Regular Record
Date, and such defaulted interest shall instead be payable to the person in
whose name this Subordinated Debenture is registered on the special record date
for such defaulted interest or other specified date determined in accordance
with the Indenture and the Supplemental Indenture referred to on the reverse
hereof.

      Payment of the principal of and any such interest on this Subordinated
Debenture will be made at the Corporate Trust Office of the Trustee, in such
coin or currency of the United States of America as at the time of payment is
legal tender for payment of public and private debts, provided, however, that at
the option of the Company payment of interest may be paid (i) by check mailed to
the address of the person entitled thereto as such address shall appear in the
Security Register for Subordinated Debentures or (ii) by wire transfer to an
account maintained by the person entitled thereto as specified in such Register.

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

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      Unless the certificate of authentication hereon has been executed by the
Trustee referred to on the reverse hereof by manual signature, this Subordinated
Debenture shall not be entitled to any benefit under the Indenture and
Supplemental Indenture referred to on the reverse hereof or be valid or
obligatory for any purpose.

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      IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed.

Dated: July 26, 2005

                                           W. R. BERKLEY CORPORATION

                                           By:__________________________________
                                           Name:
                                           Title:

      This is one of the Securities of the series described in the
within-mentioned Indenture.

                                           THE BANK OF NEW YORK, as Trustee

                                                By:_____________________________
                                                   Authorized Signatory

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                    FORM OF REVERSE OF SUBORDINATED DEBENTURE

      This Subordinated Debenture is one of a duly authorized issue of
securities of the Company (herein called the "Securities"), issued and to be
issued in one or more series under a Subordinated Indenture, dated as of the
date hereof (herein, together with Supplemental Indenture (as defined below)
called the "Indenture"), from the Company to The Bank of New York (herein called
the "Trustee", which term includes any successor trustee under the Indenture),
to which Indenture reference is hereby made for a statement of the respective
rights, limitations of rights, duties and immunities thereunder of the Company,
the Trustee, the holders of Senior Indebtedness and the Holders of the
Securities and of the terms upon which the Securities are, and are to be,
authenticated and delivered. This Security is one of the series designated on
the face hereof, limited in aggregate principal amount to $_________ and is
issued pursuant to Supplemental Indenture, dated as of July 26, 2005 from the
Company to the Trustee, relating to the Securities of this series (herein called
"Supplemental Indenture").

      The indebtedness evidenced by this Security is to the extent provided in
the Indenture, subordinate and junior in right of payment to all Company Senior
Indebtedness, and this Security is issued subject to the provisions of the
Indenture with respect thereto. Each Holder of this Security, by accepting the
same, (a) agrees to and shall be bound by such provisions, (b) authorizes and
directs the Trustee on his behalf to take such action as may be necessary or
appropriate to acknowledge or effectuate the subordination so provided and (c)
appoints the Trustee his attorney-in-fact for any and all such purposes. Each
Holder hereof, by his acceptance hereof, hereby waives all notice of the
acceptance of the subordination provisions contained herein and in the Indenture
by each holder of Company Senior Indebtedness, whether now outstanding or
hereafter incurred, and waives reliance by each such holder upon said
provisions.

      The Securities of this series are subject to redemption at any time in
whole or from time to time in part, on or after July 26, 2010, but prior to
their Stated Maturity, upon not less than 30 nor more than 60 days' notice, at a
redemption price equal to 100% of the principal amount of the Securities to be
redeemed plus any accrued and unpaid interest, including Additional Sums (as
defined in Section 10.9 of the Indenture), if any, to the date fixed for
redemption (the "Redemption Price").

      The Company will have the right at any time to dissolve the Trust and
cause the Securities to be distributed to the holders of the Trust Securities in
accordance with the Trust Agreement.

      If, at any time, a Tax Event or an Investment Company Event (each a
"Special Event") has occurred and is continuing, the Company shall have the
right, upon not less than 30 nor more than 60 days notice, to redeem the
Securities in whole but not in part, for cash in the amount of the Redemption
Price, within 90 days following the occurrence of such Special Event, and,
following such redemption, Trust Securities with an aggregate liquidation amount
equal to the aggregate principal amount of the Securities so redeemed shall be
redeemed by the Trust at the Redemption Price; provided, however, that if at the
time there is available to the Company or the Trust the opportunity to
eliminate, within such 90-day period, the Tax Event by taking some ministerial
action, such as filing a form or making an election or pursuing some other
similar reasonable measure that has no adverse effect on the Trust, the Company
or the holders of the

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Trust Securities, the Company or the Trust will pursue such measure in lieu of a
redemption. If the Company does not elect either to distribute the Securities to
the holders of the Preferred Securities in liquidation of the Trust or to redeem
the Securities, the Trust Securities shall remain outstanding and, in the event
a Special Event is continuing, Additional Sums (as defined in Section 10.9 of
the Indenture) will be payable on the Securities.

      In the event of redemption of this Security in part only, a new Security
or Securities of this series and of like tenor for the unredeemed portion hereof
will be issued in the name of the Holder hereof upon the cancellation hereof.

      If an Event of Default with respect to Securities of this series shall
occur and be continuing, the principal of the Securities of this series may be
declared due and payable in the manner and with the effect provided in the
Indenture.

      The Indenture contains provisions for defeasance at any time of the
indebtedness of this Security or of certain restrictive covenants and Events of
Default with respect to this Security, in each case upon compliance by the
Company with certain conditions set forth therein, which provisions apply to
this Security.

      The Indenture 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 the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of at least a majority in aggregate principal amount of
the Securities at the time Outstanding of each series to be affected. The
Indenture also contains provisions permitting the Holders of specified
percentages in principal amount of the Securities of each series at the time
Outstanding, on behalf of the Holders of all Securities of such series, to waive
compliance by the Company with certain provisions of the Indenture and certain
past defaults under the Indenture and their consequences. Any such consent or
waiver by the Holder of the Security shall be conclusive and binding upon such
Holder and upon all future Holders of this Security and of any Security issued
upon the registration of transfer hereof or in exchange herefor or in lieu
hereof, whether or not notation of such consent or waiver is made upon this
Security.

      No reference herein to the Indenture or to the Supplemental Indenture and
no provision of this Security or of the Indenture or the Supplemental Indenture
shall alter or impair the obligation of the Company, which is absolute and
unconditional, to pay the principal of, and interest on, this Security at the
times, place and rate, and in the coin or currency, herein prescribed.

      As provided in the Indenture and subject to certain limitations as therein
set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for registration of transfer at the
office or agency of the Company in any place where the principal of and interest
on this Security are payable, duly endorsed by, or accompanied by a written
instrument of transfer in form satisfactory to the Company, the Trustee and the
Registrar duly executed by the Holder hereof or his attorney duly authorized in
writing, and thereupon one or more new Securities of this series and of like
tenor, of authorized denominations and for the same aggregate principal amount,
will be issued to the designated transferee or transferees.

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      The Securities of this series are issuable only in registered form without
coupons in denominations of $1,000 and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations therein set forth,
Securities of this series are exchangeable for a like aggregate principal amount
of Securities of this series of like tenor of a different authorized
denomination, as requested by the Holder surrendering the same.

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

      Prior to due presentment of this Security 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 Security is registered as the owner hereof for all
purposes, whether or not the Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

      The Company and the Holder of this Security agree (i) that for United
States federal, state and local tax purposes it is intended that this Security
constitute indebtedness and (ii) to file all United States federal, state and
local tax returns and reports on such basis (unless the Company or such Holder,
as the case may be, shall have received an opinion of independent nationally
recognized tax counsel to the effect that as a result of a change in law after
the date of the issuance of this Security the Company or such Holder, as the
case may be, is prohibited from filing on such basis).

      All terms used in this Security which are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

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