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                                                                     EXHIBIT 4.6


                      FORM OF CAPITAL SECURITY CERTIFICATE

                           [FORM OF FACE OF SECURITY]

     [IF THIS CAPITAL SECURITY IS A GLOBAL CAPITAL SECURITY, INSERT: THIS
CAPITAL SECURITY IS A GLOBAL CAPITAL SECURITY WITHIN THE MEANING OF THE
DECLARATION HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE
DEPOSITORY TRUST COMPANY (THE "CLEARING AGENCY") OR A NOMINEE OF THE CLEARING
AGENCY. THIS CAPITAL SECURITY IS EXCHANGEABLE FOR CAPITAL SECURITIES REGISTERED
IN THE NAME OF A PERSON OTHER THAN THE CLEARING AGENCY OR ITS NOMINEE ONLY IN
THE LIMITED CIRCUMSTANCES DESCRIBED IN THE DECLARATION AND NO TRANSFER OF THIS
CAPITAL SECURITY (OTHER THAN A TRANSFER OF THIS CAPITAL SECURITY AS A WHOLE BY
THE CLEARING AGENCY TO A NOMINEE OF THE CLEARING AGENCY OR BY A NOMINEE OF THE
CLEARING AGENCY TO THE CLEARING AGENCY OR ANOTHER NOMINEE OF THE CLEARING
AGENCY) MAY BE REGISTERED EXCEPT IN LIMITED CIRCUMSTANCES.

     UNLESS THIS CAPITAL SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
OF THE CLEARING AGENCY TO THE TRUST OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY CAPITAL SECURITY ISSUED IS REGISTERED IN THE NAME
OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF
THE CLEARING AGENCY 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 SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

     [THE HOLDER OF THIS CAPITAL SECURITY BY ITS ACCEPTANCE HEREOF ALSO AGREES,
REPRESENTS AND WARRANTS THAT IT IS NOT AN EMPLOYEE BENEFIT, INDIVIDUAL
RETIREMENT ACCOUNT OR OTHER PLAN OR ARRANGEMENT SUBJECT TO TITLE I OF THE
EMPLOYEE RETIREMENT INCOME SECURITY ACT OF 1974, AS AMENDED ("ERISA"), OR
SECTION 4975 OF THE INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE") (EACH
A "PLAN"), OR AN ENTITY WHOSE UNDERLYING ASSETS INCLUDE "PLAN ASSETS" BY REASON
OF ANY PLAN'S INVESTMENT IN THE ENTITY AND NO PERSON INVESTING "PLAN ASSETS" OF
ANY PLAN MAY ACQUIRE OR HOLD THE CAPITAL SECURITIES OR ANY INTEREST THEREIN,
UNLESS SUCH PURCHASER OR HOLDER IS ELIGIBLE FOR THE EXEMPTIVE RELIEF AVAILABLE
UNDER U.S. DEPARTMENT OF LABOR PROHIBITED TRANSACTION CLASS EXEMPTION 96-23,
95-60, 91-38, 90-1 OR 84-14 OR ANOTHER APPLICABLE EXEMPTION OR ITS PURCHASE AND
HOLDING OF CAPITAL SECURITIES IS NOT PROHIBITED BY SECTION 406 OF ERISA OR
SECTION 4975 OF THE CODE WITH RESPECT TO SUCH PURCHASE OR HOLDING. ANY PURCHASER
OR HOLDER OF THE CAPITAL SECURITIES OR ANY INTEREST THEREIN WILL BE DEEMED TO
HAVE REPRESENTED BY ITS PURCHASE AND


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HOLDING THEREOF THAT EITHER (i) IT IS NOT AN EMPLOYEE BENEFIT PLAN WITHIN THE
MEANING OF SECTION 3(3) OF ERISA, OR A PLAN TO WHICH SECTION 4975 OF THE CODE IS
APPLICABLE, A TRUSTEE OR OTHER PERSON ACTING ON BEHALF OF AN EMPLOYEE BENEFIT
PLAN OR PLAN, OR ANY OTHER PERSON OR ENTITY USING THE ASSETS OF ANY EMPLOYEE
BENEFIT PLAN OR PLAN TO FINANCE SUCH PURCHASE, OR (ii) SUCH PURCHASE WILL NOT
RESULT IN A PROHIBITED TRANSACTION UNDER SECTION 406 OF ERISA OR SECTION 4975 OF
THE CODE FOR WHICH THERE IS NO APPLICABLE STATUTORY OR ADMINISTRATIVE
EXEMPTION.]

In all circumstances, each Capital Security Certificate shall bear the following
legend:

     THE CAPITAL SECURITIES WILL BE ISSUED AND MAY BE TRANSFERRED ONLY IN BLOCKS
HAVING A LIQUIDATION AMOUNT OF NOT LESS THAN $100,000 (100 CAPITAL SECURITIES)
AND MULTIPLES OF $1,000 IN EXCESS THEREOF. ANY ATTEMPTED TRANSFER OF CAPITAL
SECURITIES IN A BLOCK HAVING A LIQUIDATION AMOUNT OF LESS THAN $100,000 (100
CAPITAL SECURITIES) SHALL BE DEEMED TO BE VOID AND OF NO LEGAL EFFECT
WHATSOEVER. ANY SUCH PURPORTED TRANSFEREE SHALL BE DEEMED NOT TO BE THE HOLDER
OF SUCH CAPITAL SECURITIES FOR ANY PURPOSE, INCLUDING, BUT NOT LIMITED TO, THE
RECEIPT OF DISTRIBUTIONS ON SUCH CAPITAL SECURITIES, AND SUCH PURPORTED
TRANSFEREE SHALL BE DEEMED TO HAVE NO INTEREST WHATSOEVER IN SUCH CAPITAL
SECURITIES.

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Certificate Number: [                ]     Aggregate Liquidation Amount:
                                           $
CUSIP Number: [              ]              -------------


                    Certificate Evidencing Capital Securities

                                       of

                         BFD Preferred Capital Trust II

                     10.875% Capital Securities, Series A B
                (liquidation amount $1,000 per Capital Security)

     BFD Preferred Capital Trust II, a statutory business trust created under
the laws of the State of Delaware (the "Trust"), hereby certifies that {CEDE &
CO.} {NAME OF IAI} (the "Holder") is the registered owner of $_________ in
aggregate liquidation amount of Capital Securities of the Trust](1) [_________
is the registered owner of the aggregate liquidation amount of Capital
Securities of the Trust specified in Schedule A hereto](2) representing
undivided preferred beneficial interests in the assets of the Trust designated
the 10.875% Capital Securities, Series B (liquidation amount $1,000 per Capital
Security) (the "Capital Securities"). The Capital 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 Capital Securities represented hereby are
issued and shall in all respects be subject to the provisions of the Amended and
Restated Declaration of Trust, dated as of September 22, 2000, as the same may
be amended from time to time (the "Declaration"), including the designation of
the terms of the Capital Securities as set forth in Annex I to the Declaration.
Capitalized terms used but not defined herein shall have the meaning given them
in the Declaration. The Sponsor will provide a copy of the Declaration, the
Capital Securities Guarantee and the Indenture (including any supplemental
indenture) to a 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 Declaration
and is entitled to the benefits thereunder and to the benefits of the Capital
Securities Guarantee to the extent provided therein.

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



------------------

(1)  Insert in Global Capital Securities only.

(2)  Insert in Definitive Capital Securities only.

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     IN WITNESS WHEREOF, the Trust has executed this certificate this _____ day
of _____________, 2001.


                                       BFD PREFERRED CAPITAL TRUST II


                                       By:
                                          ----------------------------
                                          David F. Holland
                                          Administrative Trustee



                PROPERTY TRUSTEE'S CERTIFICATE OF AUTHENTICATION

     This is one of the 10.875% Capital Securities, Series B of BFD Preferred
Capital Trust II referred to in the within-mentioned Declaration.

Dated:                                                , 2001
       -----------------------------------------------


                                      WILMINGTON TRUST COMPANY,
                                      not in its individual capacity but solely
                                      as Property Trustee

                                      By:

                                         Authorized Signatory

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                          [FORM OF REVERSE OF SECURITY]


     Distributions on each Capital Security will be payable at a fixed rate per
annum of 10.875% (the "Coupon Rate") of the liquidation amount of $1,000 per
Capital 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
semi-annual period will bear interest thereon compounded semi-annually at the
Coupon Rate (to the extent permitted by applicable law). Pursuant to the
Registration Rights Agreement and the Liquidated Damages Agreement, in certain
limited circumstances the Debenture Issuer will be required to pay Liquidated
Damages (as defined in the Registration Rights Agreement and the Liquidated
Damages Agreement) with respect to the Debentures. The term "Distributions," as
used herein, includes such cash distributions and any and all such interest and
Liquidated Damages, if any, 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
legally available therefor.

     Distributions on the Capital Securities will be cumulative, will accumulate
from the most recent date to which Distributions have been paid or, if no
Distributions have been paid, from September 22, 2000 and will be payable
semi-annually in arrears on April 1 and October of each year, commencing April
1, 2001 (each, a "Distribution Date"), except as otherwise described below.
Distributions will be computed on the basis of a 360-day year of twelve 30-day
months. As long as no Event of Default has occurred and is continuing under the
Indenture, the Debenture Issuer has the right under the Indenture to defer
payments of interest by extending the interest payment period at any time and
from time to time on the Debentures for a period not exceeding 10 consecutive
semi-annual calendar periods, including the first such semi-annual period during
such extension period (each an "Extension Period"), PROVIDED THAT no Extension
Period shall end on a date other than an Interest Payment Date for the
Debentures or extend beyond the Maturity Date of the Debentures. As a
consequence of such deferral, Distributions (other than Liquidated Damages, if
any) will also be deferred. Notwithstanding such deferral, semi-annual
Distributions will continue to accumulate with interest thereon (to the extent
permitted by applicable law, but not at a rate exceeding the rate of interest
then accruing on the Debentures) at the Coupon Rate compounded semi-annually
during any such Extension Period. Prior to the termination of any Extension
Period, the Debenture Issuer may further defer payments of interest by further
extending such Extension Period; PROVIDED THAT such Extension Period, together
with all such previous and further extensions within such Extension Period, may
not (i) exceed 10 consecutive semi-annual periods, including the first
semi-annual period during such Extension Period, (ii) end on a date other than
an Interest Payment Date for the Debentures or (iii) extend beyond the Maturity
Date of the Debentures. Payments of accumulated 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.

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     Subject to receipt by the Sponsor of any and all required regulatory
approvals and to certain other conditions set forth in the Declaration and the
Indenture, the Property Trustee may, at the direction of the Sponsor, at any
time dissolve the Trust and after satisfaction of liabilities to creditors of
the Trust as provided by applicable law, cause the Debentures to be distributed
to the Holders of the Securities in liquidation of the Trust or, simultaneously
with any redemption of the Debentures, cause a Like Amount of the Securities to
be redeemed by the Trust.

     The Capital Securities shall be redeemable as provided in the Declaration.

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     The following abbreviations, when used in the inscription on the face of
this Certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

         TEN CON - as tenants in common

         TEN ENT - as tenants in the entireties

         JT TEN - as joint tenants with right of survival

         UNIF GIFT MIN ACT - under Uniform Gift to Minors Act and not as tenants

         Additional abbreviations may also be used though not in the above list.


                            -------------------------
                                   ASSIGNMENT
                            -------------------------


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


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            (Assignee's social security or tax identification number)



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                       (Address and zip code of assignee)

and irrevocably appoints
                        ------------------------------------------------------

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------------------------------------------------------------------------ agent
to transfer this Capital 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 Capital Security
Certificate)

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Signature Guarantee:







          Signature must be guaranteed by an "eligible guarantor institution"
          that is a bank, stockbroker, savings and loan association or credit
          union meeting the requirements of the Registrar, which requirements
          include membership or participation in the Securities Transfer Agents
          Medallion Program ("STAMP") or such other "signature guarantee
          program" as may be determined by the Registrar in addition to, or in
          substitution for, STAMP, all in accordance with the Securities
          Exchange Act of 1934, as amended.