Document:

<Page>

                              FINANCING COMMITMENT

                                       FOR

                               CEC RESOURCES LTD.

This Financing Commitment constitutes the whole and entire agreement between the
Borrower, CIBC and PLC and cancels and supersedes any prior agreements,
undertakings, declarations, representations and warranties, written or verbal,
among the parties in respect of the subject matter of this Financing Commitment,
including any prior Financing Commitment or arrangements.

                                                                    MAY 18, 2001

BORROWER:           CEC Resources Ltd. (the "BORROWER")

GUARANTOR:          Carbon Energy Corporation (the "GUARANTOR")

LENDER:             Canadian Imperial Bank of Commerce ("CIBC")

GAS PURCHASE AND
SALE TRANSACTIONS
FACILITATOR:        CIBC World Markets PLC or any other subsidiary of CIBC from
                    time to time ("PLC")

CONFIDENTIALITY:    This Financing Commitment will be treated in confidence by
                    the Borrower, CIBC and PLC unless disclosure is required by
                    law or other reporting or disclosure requirements.

AMOUNT:             Cdn. $14,000,000 as a revolving/term production loan (the
                    "PRODUCTION LOAN") and,

                    U.S. $3,500,000 as a swap facility (the "SWAP FACILITY")
                    (collectively, the "FACILITY").

PURPOSE OF
THE FACILITY:       PRODUCTION LOAN

                    For normal operating requirements and to assist the Borrower
                    in the exploration, development, production and/or
                    acquisition of oil and gas reserves in Western Canada.

                    SWAP FACILITY

                    To provide for the Borrower's contingent exposure under
                    commodity swaps either financially or physically settled.

HOSTILE
ACQUISITION:        The Borrower shall not utilize whether directly or
                    indirectly Availments to facilitate, assist or participate
                    in a hostile acquisition without the prior written consent
                    of CIBC which may be withheld in CIBC's sole discretion.

<Page>
                                       2

BORROWING BASE:     Subject to the satisfaction of the Conditions Precedent to
                    Funding, the Production Loan currently permits draws of up
                    to Cdn. $14,000,000, (the "BORROWING BASE") subject to
                    adjustment as herein provided, and will remain in effect
                    until expiration of the Revolving Phase.

                    CIBC will undertake at any time, but not less frequently
                    than semi-annually during the Revolving and Term phase if
                    CIBC so chooses, a review of the Borrower's oil and gas
                    properties evaluated in an independently prepared economic
                    and reserve evaluation report (provided annually) for
                    purposes of redetermining the Borrowing Base applicable to
                    the Facility. To assist in such redetermination, the
                    Borrower will provide to CIBC operating statements and such
                    other technical information with respect to the properties
                    being reviewed as CIBC may request.

                    Should CIBC determine at any time that there is a Borrowing
                    Base Shortfall, during both the Revolving Phase and the Term
                    Phase, the Borrower will, within 60 days, use whatever means
                    necessary to reduce its indebtedness under this Financing
                    Commitment by that amount stipulated by CIBC, or
                    alternatively pledge additional security to CIBC sufficient
                    to cover, in CIBC's opinion, such deficiency.

                    While a Borrowing Base Shortfall exists, the Borrower shall:

                    *    not request new Availments;

                    *    provide CIBC with information needed to determine the
                         Borrower's Available Cash Flow;

                    *    dedicate on a monthly basis for repayment of this
                         Financing Commitment such portion of its Available Cash
                         Flow as is required to eliminate the Borrowing Base
                         Shortfall within 60 days from the date CIBC delivers
                         notice to the Borrower of the Borrowing Base Shortfall;
                         and

                    *    pay the increased compensation required under the
                         heading "Borrowing Base Rate Shortfall or Event of
                         Default".

PRODUCTION LOAN
AVAILABILITY:       The Production Loan can be advanced by way of any
                    combination of the following availments:

                    *    overdraft borrowings in Canadian dollars;

                    *    letters of credit, letters of guarantee, cheque
                         credits, bid cheques for out of Province land sales and
                         corporate visa (collectively the "SUNDRY OPTIONS").

SWAP FACILITY
AVAILABILITY:       At the Borrower's request and subject to market
                    availability, CIBC and/or PLC will provide quotes for (i)
                    forward rate agreements to provide fixed or floating rate
                    funding for part or all of the Production Loan, (ii)
                    commodity swaps covering a portion of the Borrower's oil and
                    gas production, (iii) forward exchange contracts and (iv)
                    firm gas purchase and sale transactions, subject to the
                    following:

                    o    Forward Rate Agreements - terms shall not exceed the
                         lesser of two years and the date of expiry or
                         termination of the Production Loan, with
<Page>
                                       3

                         aggregate amounts hedged not to exceed 60% of the
                         average Principal Indebtedness outstanding during the
                         Borrower's previous fiscal quarter;

                    o    Commodity Swaps - terms shall not exceed the lesser of
                         two years and the date of expiry or termination of the
                         Production Loan, with aggregate production volumes
                         hedged from all sources, for both natural gas and oil,
                         (calculated separately, not collectively) not to exceed
                         60% of the Borrower's average production as forecast by
                         CIBC.

                    o    Forward Exchange Contracts - terms shall not exceed the
                         lesser of two years and the date of expiry or
                         termination of the Production Loan, with aggregate
                         amounts hedged not to exceed 60% of the Borrower's
                         applicable foreign revenue;

                    o    Physical Gas Purchase and Sale Transactions - terms and
                         conditions as outlined in the Master Firm Gas
                         Purchase/Sale Agreement, terms shall not exceed the
                         lesser of two years and the date of expiry or
                         termination of the Production Loan, with aggregate
                         production volumes hedged from natural gas not to
                         exceed 60% of the Borrower's current daily production
                         volume as determined by CIBC;

                    provided that in all instances, the Borrower's contingent
                    liability to CIBC and/or PLC under the Swap Facility shall
                    be secured and rank PARI PASSU with the Principal
                    Indebtedness.

                    Notwithstanding the foregoing, the sum of the aggregate
                    production volumes hedged with CIBC and/or PLC from natural
                    gas under both the commodity swaps and physical gas purchase
                    and sale transactions described above shall not at any time
                    exceed 60% of the Borrower's current daily production
                    volumes of natural gas as determined by CIBC.

TERM AND
REPAYMENT:          The Production Loan will revolve and fluctuate at the
                    Borrower's option until August 31, 2001 (the "REVOLVING
                    PHASE") with interest payable monthly in arrears. At the
                    request of the Borrower, the Production Loan may be renewed
                    upon such terms and for such period, and subject to the
                    requirements listed below, as CIBC may in its discretion
                    agree to (a "REVOLVING PERIOD"). CIBC may elect to renew all
                    or only a portion of the Production Loan for a further
                    Revolving Phase.

                    REVOLVING PHASE

                    While the Production Loan is in the Revolving Phase, the
                    Borrower may, at least 60 days prior to the termination of
                    the then current Revolving Phase, request an extension of
                    the Revolving Phase provided:

                    *    the extension is for 364 days or less;

                    *    the extension will not result in the then current
                         Revolving Period extending beyond 364 days; and

                    *    CIBC, in its unrestricted discretion, consents to the
                         extension.
<Page>
                                       4

                    An extension of the Revolving Phase will create a new and
                    separate Revolving Phase which in turn can only be extended
                    as provided above.

                    Upon the expiration or termination of the then current
                    Revolving Phase, any amount undrawn under the Production
                    Loan will be permanently cancelled.

                    TERM PHASE

                    During the Term Phase, the Production Loan will be
                    permanently reduced by way of consecutive monthly principal
                    payments commencing 30 days after the end of the Revolving
                    Phase over an amortization period consistent with the
                    Borrower's cash flow profile, as determined by CIBC, by
                    applying its usual practice for similar type loans in
                    comparable circumstances, provided that such amortization
                    period shall not exceed 36 months.

                    Where used herein, the term "TERM PHASE" means the period
                    commencing immediately after the end of the Revolving Phase
                    until repayment of the Production Loan in full.

PREPAYMENT AND
CANCELLATION:       The Borrower may permanently prepay the Facility in whole or
                    in part, subject to the following:

                    *    All prepayments, during the Term Phase, will be made in
                         inverse order of maturity;

                    *    Availments by way of commodity swaps (financial or
                         physical), forward rate agreements and forward exchange
                         contracts may be prepaid only at maturity except where
                         the Borrower agrees to pay CIBC's breaking costs due to
                         early redemption of offsetting positions or otherwise,
                         including all costs associated with reversing
                         positions, provided such early redemption is possible;
                         and

                    *    the Borrower may at any time, upon giving CIBC two
                         Banking Days prior notice, cancel any unused part of
                         the Facility and any cancelled portion will not be
                         reinstated.

RATES AND
STAMPING FEES:      REVOLVING PHASE

                    *    CIBC Prime Rate in effect from time to time plus 1/2 of
                         1% per annum with interest payable monthly in arrears.

                    TERM PHASE

                    *    CIBC Prime Rate in effect from time to time plus 1 1/2%
                         per annum with interest payable monthly in arrears.

STANDBY FEE:        During the Revolving Phase, a Standby Fee of 1/4 of 1% per
                    annum calculated on the undrawn portion of the available and
                    unused Production Loan is payable monthly in arrears.

RENEWAL FEE:        $20,000 is payable upon the Borrower's acceptance of the
                    terms and conditions hereof.
<Page>
                                       5

SUNDRY OPTIONS:     Fees on Sundry Options are subject to change without notice
                    and are payable as follows:

                    Letters of Credit/     -  1.3% per annum or portion thereof
                    Letters of Guarantee      in advance with a minimum of $150
                    Corporate Visa         -  CIBC standard rates
                    Bid Cheques            -  2.0% per annum plus $10.00 per
                                              cheque for out of province Bid
                                              Cheque transactions

BORROWING BASE
SHORTFALL OR
EVENT OF DEFAULT:   Effective on the 30th day following receipt by the Borrower
                    of a notice of a Borrowing Base Shortfall or an Event of
                    Default (the "Effective Date"), the interest rates then
                    applicable to CIBC Prime Rate loans shall increase by 2% per
                    annum and such increase shall remain in effect for as long
                    as a Borrowing Base Shortfall or Event of Default subsists.

LEGAL FEES:         CIBC's costs, including legal and the cost to prepare any
                    environmental assessments, in connection with the
                    preparation, establishment, operation or enforcement of this
                    Financing Commitment, including the Security, are for the
                    account of the Borrower.

SECURITY:           The Borrower will provide to CIBC and PLC and maintain the
                    following as security for all obligations of the Borrower
                    arising under this Financing Commitment, including any
                    liability or exposure of CIBC under the Sundry Options and
                    CIBC and/or PLC under the Swap Facility;

                    *    Acknowledgement, in form satisfactory to CIBC, from the
                         Borrower to CIBC and PLC that all previous Security
                         granted to CIBC by the Borrower under any existing
                         facility or any other previous facilities including,
                         without limitation, the financing commitments dated
                         November 25, 1998, October 8, 1999 and September 15,
                         2000, remains in full force and effect;

                    *    a Second Supplemental Debenture in the amount of
                         $25,000,000 conveying a first floating charge (with
                         right to fix) over all the present and after-acquired
                         property of the Borrower together with a pledge
                         thereof;

                    *    Negative pledge from CEC Resources Ltd. and undertaking
                         to provide fixed charge security;

                    *    Guarantee from Carbon Energy Corporation with respect
                         to the unconditional guarantee of the Borrower's
                         indebtedness to CIBC and PLC (containing an
                         acknowledgement that the Negative Pledge dated October
                         6, 2000 granted by the Guarantor continues in full
                         force and effect), together with a legal opinion of the
                         Guarantor's counsel in support thereof, in form
                         satisfactory to CIBC;

                    *    General Security Agreement providing a first priority
                         security interest in all present and after-acquired
                         personal property of the Borrower;

                    *    Officer's certificate certifying ownership of
                         properties and interests as evaluated by CIBC;

                    *    Standard CIBC agreement respecting hydrocarbons;
<Page>
                                       6

                    *    Standard CIBC agreement and documentation relative to
                         Sundry Options;

                    *    Standard CIBC overdraft lending agreement;

                    *    Standard ISDA form agreement relative to swap
                         transactions, (when required);

                    *    Master Firm Gas Purchase/Sale Agreement with any
                         relating documents as required by CIBC or its counsel,
                         (when required); and

                    *    Any and all other security or documents as required by
                         CIBC or its counsel.

                    (collectively the "Security").

                    In the event of any conflict between this Financing
                    Commitment and the Security, this Financing Commitment shall
                    govern.

OTHER COVENANT:     The Borrower covenants not to provide any financial support
                    by guarantee, pledge of its shares, granting of a security
                    interest or other mortgage, charge, lien or encumbrance of
                    any kind, or otherwise to an affiliate (as such term is
                    defined in the BUSINESS CORPORATIONS ACT (Alberta)) without
                    the prior written consent of CIBC, in its sole discretion.

UNDERTAKING:        Upon request, the Borrower agrees to provide CIBC with such
                    additional security that in CIBC's reasonable opinion is
                    required to cover its or PLC's contingent exposure and all
                    indebtedness under the Swap Facility, including without
                    limitation, an acknowledgement and amending agreement and
                    such other documentation as CIBC may request to confirm that
                    the Security held by CIBC as at date hereof secures such
                    contingent exposure and indebtedness to PLC and to amend the
                    Security accordingly.

CONDITIONS
PRECEDENT
TO FUNDING:         CIBC's obligation to provide increased Availments shall be
                    subject to the following conditions precedent being met,
                    unless waived in writing by CIBC:

                    *    execution of the Financing Commitment;

                    *    the Security in form and substance satisfactory to
                         CIBC;

                    *    the receipt by CIBC of a duly executed environmental
                         certificate in CIBC's standard form;

                    *    no Event of Default shall have occurred nor any event
                         which, after notice or lapse of time or both, would
                         become an Event of Default; and

                    *    the appropriate notice of borrowing shall have been
                         delivered in accordance with the notice provisions
                         provided herein.

ADDITIONAL
CONDITION:          In addition to the conditions set forth above, CIBC's
                    obligation to provide Availments, other than rollovers or
                    conversions of a then maturing advance, shall be suspended
                    for as long as there exists a Borrowing Base Shortfall.
<Page>
                                       7

REPORTING
REQUIREMENTS:       The Borrower will provide to CIBC:

                    *    audited financial statements of the Guarantor within
                         120 days of the Borrower's fiscal year-end;

                    *    the Guarantor's quarterly 10 Q filings within 60 days
                         of the end of the first three fiscal quarters of each
                         fiscal year;

                    *    unaudited annual financial statements of the Borrower
                         within 120 days of the Borrower's fiscal year-end;

                    *    unaudited quarterly financial statements within 60 days
                         of the end of the first three fiscal quarters of each
                         fiscal year;

                    *    an independently prepared economic and reserve
                         evaluation report covering the Borrower's oil and gas
                         properties along with annual cash flow projections and
                         capital expenditure budgets within 90 days of the end
                         of each fiscal year;

                    *    at the request of CIBC, production revenue statements
                         on a monthly basis within 60 days of each month end,
                         such statements indicating the gross oil and gas
                         production, net production, total revenues, royalties
                         and other burdens, operating expenses and net revenues,
                         in a format acceptable to CIBC;

                    *    compliance certificate substantially in the form of
                         Schedule B hereto within 60 days of the end of each
                         fiscal quarter; and

                    *    such other documentation and information as CIBC may
                         reasonably request, including any internally or
                         independently prepared environmental assessment reports
                         in the Borrower's possession.

DISPOSITION
LIMIT:              In addition to the Borrower's covenants found in Schedule A
                    hereto, the Borrower will not sell, convey or otherwise
                    dispose of any of its Proved Producing Reserves or related
                    facilities, other than in the normal course of business and
                    on arm's length terms, provided that, if cumulative proceeds
                    of all dispositions to be received by the Borrower exceed
                    $1,000,000 in any calendar year, such proceeds will be used
                    to permanently repay the Principal Indebtedness, unless
                    other arrangements are made with CIBC.

CHANGE
OF CONTROL:         The Borrower shall notify CIBC of a Change of Control as
                    soon as it becomes aware thereof, and CIBC may at its sole
                    discretion, by written notice to the Borrower, terminate the
                    Facility upon a Change of Control occurring. Such
                    termination will be effective on the 30th day following the
                    giving of the notice by CIBC and thereupon all Principal
                    Indebtedness, interest, fees and all amounts due by the
                    Borrower to CIBC or PLC under the Facility will be due and
                    payable.

INDEMNITY:          The Borrower agrees to indemnify and hold CIBC and its
                    officers, directors, employees and agents harmless against
                    any and all liabilities and costs associated with or as a
                    result of CIBC and PLC entering into and performing their
                    obligations under this Financing Commitment, including but
                    not limited to liabilities
<Page>
                                       8

                    or costs associated with or as a result of (i) any
                    transaction financed or to be financed in whole or part,
                    directly or indirectly, by the proceeds of this Facility; or
                    (ii) any breach or non-compliance of any legislation, order,
                    directive or judgment by the Borrower for the protection of
                    the environment. This indemnity will survive the repayment,
                    cancellation or termination of this Financing Commitment.

NOTICES:            Any notice or communication to be given hereunder and under
                    the Security may be effectively given by delivering the same
                    at the addresses hereinafter set forth or by telecopy or by
                    sending the same by prepaid registered mail to the parties
                    at such addresses. Any notice so mailed will be deemed to
                    have been given upon actual receipt thereof. The address of
                    the parties are:

                    CEC Resources Ltd.
                    1750, 530 - 8th Avenue S.W.
                    Calgary, Alberta
                    T2P 3S8

                    Attention: Robert R. Morrison
                               President
                    Telecopy:  (403) 262-8167

                    Canadian Imperial Bank of Commerce
                    Oil and Gas Group
                    10th Floor Bankers Hall
                    855 - 2nd Street S.W.
                    Calgary, Alberta
                    T2P 2P2

                    Attention: Vice President, Oil & Gas
                    Telecopy:  (403) 221-5779

                    Either party may from time to time notify the other, in
                    accordance with the provisions hereof, of any change of
                    address or addressee, which thereafter, until changed by
                    like notice, will be the address of such party for all
                    purposes of this Financing Commitment and the Security.

GENERAL TERMS
AND CONDITIONS:     Schedule A hereto contains general definitions, covenants,
                    events of default, terms and conditions which form part of
                    this Financing Commitment.
<Page>
                                       9

PRIOR
INDEBTEDNESS:       All amounts owing by the Borrower as at the effective date
                    hereof under any other financing commitment or agreement
                    shall be deemed to be amounts owing under this Facility and
                    this Financing Commitment as of the effective date hereof.

                    OUR FINANCING COMMITMENT IS OPEN TO ACCEPTANCE BY YOU ON OR
                    PRIOR TO JUNE 29, 2001.

                    CANADIAN IMPERIAL BANK OF COMMERCE

                    Per:
                         ---------------------------------------------
                    Name: David W. Richardson
                    Title: Vice President

                    Per:
                        ---------------------------------------------
                    Name: Scott Daniel
                    Title: Manager, Commercial Banking

                    THE ABOVE TERMS AND CONDITIONS AND THOSE CONTAINED IN THE
                    ATTACHED SCHEDULE "A" ARE AGREED TO BE EFFECTIVE THE 29TH
                    DAY OF JUNE, 2001.

                    CEC RESOURCES LTD.

                    Per:
                        ---------------------------------------------
                    Name: Robert Morrison
                    Title: President

                    Per:
                        ---------------------------------------------
                    Name: Kevin D. Struzeski
                    Title: Treasurer<Page>
                                                                   EXHIBIT 10.52

                                    RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                               BIRCH TELECOM, INC.

    BIRCH TELECOM, INC., a corporation organized and existing under the laws of
the State of Delaware, certifies as follows:

    1. The original Certificate of Incorporation of Birch Telecom, Inc. was
filed with the Delaware Secretary of State on December 23, 1996.

    2. This Restated Certificate of Incorporation amends and restates the
provisions of the Restated Certificate of Incorporation of this Corporation, and
was duly adopted in accordance with Sections 245 and 242 of the General
Corporation Law of the State of Delaware by the directors and stockholders of
the Corporation.

    3. The text of the Certificate of Incorporation is amended and restated to
read in its entirety as set forth below:

    FIRST: The name of the Corporation is Birch Telecom, Inc. (the
"Corporation").

    SECOND: The address of the Corporation's registered office in the State of
Delaware is 2711 Centerville Road, Suite 400, Wilmington, County of New Castle,
Delaware 19808, and the name of its registered agent at such address is the
Corporation Service Company.

    THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the Delaware General
Corporation Law.

    FOURTH:

A.  The total number of shares that the Corporation shall have authority to
issue is 1,250,000,000 shares. The total number of shares of common stock that
the Corporation shall have authority to issue is 850,000,000 shares (the "Common
Stock"), and the par value of each share of Common Stock is $0.001. The total
number of shares of preferred stock that the Corporation shall have authority to
issue is 400,000,000 shares (the "Preferred Stock"), and the par value of each
share of Preferred Stock is $0.001.

    This Restated Certificate of Incorporation shall become effective in
accordance with the General Corporation Law of the State of Delaware (such time
of effectiveness, the "Effective Time").

                                       1
<Page>

B.  The Preferred Stock may be issued from time to time in one or more
series. The Board of Directors is expressly authorized to provide for the
issuance of all or any number of shares of Preferred Stock in one or more
classes or series, and to fix for each such class or series, the voting powers,
full or limited, or no voting powers, and such designations, preferences and
relative, participating, optional or other special rights, and qualifications,
limitations or restrictions thereof, as shall be stated and expressed in the
resolution or resolutions adopted by the Board of Directors provided for the
issuance of such class or series and as may be permitted by the Delaware General
Corporation Law and this Restated Certificate of Incorporation, including but
not limited to fixing the dividend rights, dividend rate, conversion rate,
voting rights, rights and terms of redemption (including sinking fund
provisions), the redemption price or prices, the liquidation preferences of any
wholly unissued series of Preferred Stock, and the number of shares constituting
any such series and the designation thereof, or any of them; and to increase or
decrease the number of shares of any series subsequent to the issue of shares of
that series, but not below the number of shares of such series then outstanding.
In case the number of shares of any series shall be so decreased, the shares
constituting such decrease shall resume the status which they had prior to the
adoption of the resolution originally fixing the number of shares of such
series.

    Of the authorized shares of Preferred Stock, 8,750,000 shares are hereby
designated "Series B Preferred Stock"; 8,500,000 shares are hereby designated
"Series C Preferred Stock"; 3,000,000 shares are hereby designated "Series D
Preferred Stock"; 30,000,000 shares are hereby designated "Series F Preferred
Stock"; 329,000,000 shares are hereby designated "Series G Preferred Stock";
6,579,000 shares are hereby designated "Series H Preferred Stock"; and 2,223,000
shares are hereby designated "Series I Preferred Stock."

C.  The powers, preferences, rights, restrictions and other matters
relating to the Series B Preferred Stock, Series C Preferred Stock, Series D
Preferred Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
Preferred Stock and Series I Preferred Stock are as follows:

        (1) Dividends.

        (a) SERIES B PREFERRED STOCK. The holders of Series B Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to $1.52 plus all unpaid
    dividends accrued on such shares of Series B Preferred Stock, on each
    outstanding share of Series B Preferred Stock (as adjusted for any stock
    dividends, combinations, splits and the like with respect to such shares),
    when and as declared by the Board of Directors out of the funds legally
    available for that purpose. Such dividends shall be cumulative from the date
    of issuance of the Series B Preferred Stock, whether or not earned, whether
    or not funds of the Corporation are legally available for the payment of
    dividends and whether or not declared by the Board of Directors, but such
    dividends shall be payable only when, as, and if declared by the Board of
    Directors. So long as any shares of Series B Preferred Stock shall be
    outstanding, no dividend, whether in cash, stock or property, shall be paid
    or declared, nor shall any other distribution be made, on any shares of
    Series C Preferred Stock, Common Stock or any other class or series of
    capital stock of the Corporation authorized or issued after the Effective
    Time, the terms of which do not expressly provide that it ranks senior to or
    on a parity with the Series B Preferred Stock as to dividends ("B Junior

                                       2
<Page>

    Securities"), nor shall any shares of Series C Preferred Stock, Common Stock
    or any other class or series of B Junior Securities be purchased, redeemed
    or otherwise acquired for value by the Corporation (except for acquisitions
    of Common Stock by the Corporation pursuant to agreements which permit the
    Corporation to repurchase such shares upon termination of services to the
    Corporation, in exercise of the Corporation's right of first refusal upon a
    proposed transfer, and for payments of cash in lieu of fractional shares
    pursuant to Section (4)(n) below) until all dividends set forth in this
    Section (1)(a) on the Series B Preferred Stock shall have been paid or
    declared and set apart. So long as any shares of Series B Preferred Stock
    shall be outstanding, no dividend, whether in cash or property, shall be
    paid or declared, nor shall any other distribution be made, on any shares of
    Series D Preferred Stock, Series H Preferred Stock, Series I Preferred Stock
    or any other class or series of capital stock of the Corporation authorized
    and issued after the Effective Time, the terms of which expressly provide
    that it will rank on a parity with the Series B Preferred Stock as to
    dividends ("B Parity Securities"), nor shall any shares of Series D
    Preferred Stock, Series H Preferred Stock, Series I Preferred Stock or any
    other class or series of B Parity Securities be purchased, redeemed or
    otherwise acquired for value by the Corporation (except for exercises of the
    Corporation's right of first refusal upon a proposed transfer, for payments
    of cash in lieu of fractional shares pursuant to Section (4)(n) below, or an
    exchange of shares of Series D Preferred Stock for shares of Series I
    Preferred Stock in accordance with one or more recapitalization agreements
    by and among the Corporation and certain holders of shares of Series B
    Preferred Stock and Series D Preferred Stock (each such agreement, a
    "Recapitalization Agreement") entered into in accordance with Section 5.11
    of the Series G Preferred Stock Purchase Agreement, dated as of March 26,
    2001 (the "Series G Purchase Agreement") between the Corporation and BTI (as
    defined below)) until all dividends set forth in this Section (1)(a) on the
    Series B Preferred Stock shall have been paid or declared and set apart,
    except if at any time the Corporation pays less than the total amount of
    dividends then accrued with respect to the Series B Preferred Stock, the
    Series D Preferred Stock, Series H Preferred Stock, Series I Preferred Stock
    and any other B Parity Securities, such payment shall be distributed ratably
    among the holders of the Series B Preferred Stock, Series D Preferred Stock,
    Series H Preferred Stock, Series I Preferred Stock and each other class or
    series of B Parity Securities entitled to receive such dividends based upon
    the aggregate accrued but unpaid dividends on such shares held by each
    holder. When dividends are not paid in full or consideration sufficient for
    such payment is not set apart as aforesaid, all dividends declared upon the
    Series B Preferred Stock, Series D Preferred Stock, Series H Preferred
    Stock, Series I Preferred Stock and any other class or series of B Parity
    Securities shall be declared ratably in proportion to the respective amounts
    of dividends accumulated and unpaid on the Series B Preferred Stock, Series
    D Preferred Stock, Series H Preferred Stock, Series I Preferred Stock and
    accumulated and unpaid on such B Parity Securities.

        (b) SERIES C PREFERRED STOCK. The holders of Series C Preferred Stock
    shall be entitled to receive dividends in cash at the rate of ten percent
    (10%) per annum on an amount equal to $1.52 on each outstanding share of
    Series C Preferred Stock (as adjusted for any stock dividends, combinations,
    splits and the like with respect to such shares), when and as declared by
    the Board of Directors out of funds legally available for that purpose.
    Notwithstanding anything to the contrary herein, such dividends shall be

                                       3
<Page>

    payable only when, as and if declared by the Board of Directors and shall
    not be cumulative. So long as any shares of Series C Preferred Stock shall
    be outstanding, no dividend, whether in cash, stock or property, shall be
    paid or declared, nor shall any other distribution be made, on any shares of
    Common Stock or any other class or series of capital stock of the
    Corporation authorized or issued after the Effective Time, the terms of
    which do not expressly provide that it ranks senior to or on a parity with
    the Series C Preferred Stock as to dividends ("C Junior Securities"), nor
    shall any shares of Common Stock or any class or series of C Junior
    Securities be purchased, redeemed or otherwise acquired for value by the
    Corporation (except for acquisitions of Common Stock by the Corporation
    pursuant to agreements which permit the Corporation to repurchase such
    shares upon termination of services to the Corporation, in exercise of the
    Corporation's right of first refusal upon a proposed transfer, or for
    payments of cash in lieu of fractional shares pursuant to Section (4)(n)
    below) until all dividends set forth in this Section (1)(b) on the Series C
    Preferred Stock shall have been paid or declared and set apart. So long as
    any shares of Series C Preferred Stock shall be outstanding, no dividend,
    whether in cash or property, shall be paid or declared, nor shall any other
    distribution be made, on any class or series of capital stock of the
    Corporation authorized and issued after the Effective Time, the terms of
    which expressly provide that it will rank on a parity with the Series C
    Preferred Stock as to dividends ("C Parity Securities"), nor shall any
    shares of any class or series of C Parity Securities be purchased, redeemed
    or otherwise acquired for value by the Corporation (except for exercises of
    the Corporation's right of first refusal upon a proposed transfer, or for
    payments of cash in lieu of fractional shares pursuant to Section (4)(n)
    below) until all dividends set forth in this Section (1)(b) on the Series C
    Preferred Stock shall have been paid or declared and set apart, except if at
    any time the Corporation pays less than the total amount of dividends then
    accrued with respect to the C Parity Securities, such payment shall be
    distributed ratably among the holders of the Series C Preferred Stock and
    each other class or series of C Parity Securities entitled to receive such
    dividends based upon the aggregate accrued but unpaid dividends on such
    shares held by each holder. When dividends are not paid in full or
    consideration sufficient for such payment is not set apart as aforesaid, all
    dividends declared upon the Series C Preferred Stock and any class or series
    of C Parity Securities shall be declared ratably in proportion to the
    respective amounts of dividends accumulated and unpaid on the Series C
    Preferred Stock and accumulated and unpaid on such C Parity Securities.

        (c) SERIES D PREFERRED STOCK. The holders of Series D Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to $4.50 plus all unpaid
    dividends accrued on such shares of Series D Preferred Stock, on each
    outstanding share of Series D Preferred Stock (as adjusted for any stock
    dividends, combinations, splits and the like with respect to such shares),
    when and as declared by the Board of Directors out of the funds legally
    available for that purpose. Such dividends shall be cumulative from the date
    of issuance of the Series D Preferred Stock, whether or not earned, whether
    or not funds of the Corporation are legally available for the payment of
    dividends and whether or not declared by the Board of Directors, but such
    dividends shall be payable only when, as, and if declared by the Board of
    Directors. So long as any shares of Series D Preferred Stock shall be
    outstanding, no dividend, whether in cash, stock or property, shall be paid
    or declared, nor shall any other distribution be made, on any shares of
    Series C Preferred Stock,

                                       4
<Page>

    Common Stock or any other class or series of capital stock of the
    Corporation authorized or issued after the Effective Time, the terms of
    which do not expressly provide that it ranks senior to or on a parity with
    the Series D Preferred Stock as to dividends ("D Junior Securities"), nor
    shall any shares of Series C Preferred Stock, Common Stock or any class or
    series of D Junior Securities be purchased, redeemed or otherwise acquired
    for value by the Corporation (except for acquisitions of Common Stock by the
    Corporation pursuant to agreements which permit the Corporation to
    repurchase such shares upon termination of services to the Corporation, in
    exercise of the Corporation's right of first refusal upon a proposed
    transfer, or for payments of cash in lieu of fractional shares pursuant to
    Section (4)(n) below) until all dividends set forth in this Section (1)(c)
    on the Series D Preferred Stock shall have been paid or declared and set
    apart. So long as any shares of Series D Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    B Preferred Stock, Series H Preferred Stock, Series I Preferred Stock or any
    other class or series of capital stock of the Corporation authorized and
    issued after the Effective Time, the terms of which expressly provide that
    it will rank on a parity with the Series D Preferred Stock as to dividends
    ("D Parity Securities"), nor shall any shares of Series B Preferred Stock,
    Series H Preferred Stock, Series I Preferred Stock or any other class or
    series of D Parity Securities be purchased, redeemed or otherwise acquired
    for value by the Corporation (except for exercises of the Corporation's
    right of first refusal upon a proposed transfer, for payments of cash in
    lieu of fractional shares pursuant to Section (4)(n) below, or an exchange
    of shares of Series B Preferred Stock for shares of Series H Preferred Stock
    in accordance with a Recapitalization Agreement) until all dividends set
    forth in this Section (1)(c) on the Series D Preferred Stock shall have been
    paid or declared and set apart, except if at any time the Corporation pays
    less than the total amount of dividends then accrued with respect to the
    Series B Preferred Stock, the Series D Preferred Stock, Series H Preferred
    Stock, Series I Preferred Stock and any other D Parity Securities, such
    payment shall be distributed ratably among the holders of the Series B
    Preferred Stock, Series D Preferred Stock, Series H Preferred Stock, Series
    I Preferred Stock and each other class or series of B Parity Securities
    entitled to receive such dividends based upon the aggregate accrued but
    unpaid dividends on such shares held by each holder. When dividends are not
    paid in full or consideration sufficient for such payment is not set apart
    as aforesaid, all dividends declared upon the Series B Preferred Stock,
    Series D Preferred Stock, Series H Preferred Stock, Series I Preferred Stock
    and any other class or series of D Parity Securities shall be declared
    ratably in proportion to the respective amounts of dividends accumulated and
    unpaid on the Series B Preferred Stock, Series D Preferred Stock, Series H
    Preferred Stock, Series I Preferred Stock and accumulated and unpaid on such
    D Parity Securities.

        (d) SERIES F PREFERRED STOCK. The holders of Series F Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to the purchase price for such
    shares (the "Purchase Price") plus all unpaid dividends accrued on such
    shares of Series F Preferred Stock, on each outstanding share of Series F
    Preferred Stock (as adjusted for any stock dividends, combinations, splits
    and the like with respect to such shares), payable on March 31, June 30,
    September 30 and December 31 of each year, when and as declared by the Board
    of Directors out of the funds legally available for that purpose. Such
    dividends shall be cumulative from the

                                       5
<Page>

    date of issuance of the Series F Preferred Stock, whether or not earned,
    whether or not funds of the Corporation are legally available for the
    payment of dividends and whether or not declared by the Board of Directors,
    but such dividends shall be payable only when, as, and if declared by the
    Board of Directors. The Purchase Price for the Series F Preferred Stock is
    (i) $4.50 per share for the initial purchase of 13,333,334 shares by BTI
    Ventures L.L.C. or its affiliates ("BTI"), (ii) $4.75 per share for the
    purchase of 5,263,158 shares of Series F Preferred Stock which were
    purchased upon the exercise of BTI's option to purchase such shares and
    (iii) $5.00 per share for the purchase of 5,000,000 shares of Series F
    Preferred Stock which were purchased upon the exercise of BTI's option to
    purchase such shares. So long as any shares of Series F Preferred Stock
    shall be outstanding, no dividend, whether in cash or property, shall be
    paid or declared, nor shall any other distribution be made, on any shares of
    Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series H Preferred Stock, Series I Preferred Stock, Common Stock or
    any other class or series of capital stock of the Corporation authorized or
    issued after the Effective Time, the terms of which do not expressly provide
    that it ranks senior to or on a parity with the Series F Preferred Stock as
    to dividends ("F Junior Securities"), nor shall any shares of Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    H Preferred Stock, Series I Preferred Stock, Common Stock or any other class
    or series of F Junior Securities be purchased, redeemed or otherwise
    acquired for value by the Corporation (except for acquisitions of Common
    Stock by the Corporation pursuant to agreements which permit the Corporation
    to repurchase such shares upon termination of services to the Corporation,
    in exercise of the Corporation's right of first refusal upon a proposed
    transfer, for payments of cash in lieu of fractional shares pursuant to
    Section (4)(n) below or an exchange of shares of Series B Preferred Stock
    for shares of Series H Preferred Stock and an exchange of shares of Series D
    Preferred Stock for shares of Series I Preferred Stock in accordance with a
    Recapitalization Agreement) until all dividends set forth in this Section
    (1)(d) on the Series F Preferred Stock shall have been paid or declared and
    set apart. So long as any shares of Series F Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    G Preferred Stock or any other class or series of capital stock of the
    Corporation authorized and issued after the Effective Time, the terms of
    which expressly provide that it will rank on a parity with the Series F
    Preferred Stock as to dividends ("F Parity Securities"), nor shall any
    shares of Series G Preferred Stock or any other class or series of F Parity
    Securities be purchased, redeemed or otherwise acquired for value by the
    Corporation (except for payments of cash in lieu of fractional shares
    pursuant to Section (4)(n) below) until all dividends set forth in this
    Section (1)(d) on the Series F Preferred Stock shall have been paid or
    declared and set apart, except if at any time the Corporation pays less than
    the total amount of dividends then accrued with respect to the Series F
    Preferred Stock, the Series G Preferred Stock and any other F Parity
    Securities, such payment shall be distributed ratably among the holders of
    the Series F Preferred Stock, the Series G

                                       6
<Page>

    Preferred Stock and each other class or series of F Parity Securities
    entitled to receive such dividends based upon the aggregate accrued but
    unpaid dividends on such shares held by each holder. When dividends are not
    paid in full or consideration sufficient for such payment is not set apart
    as aforesaid, all dividends declared upon the Series F Preferred Stock, the
    Series G Preferred Stock and any other class or series of F Parity
    Securities shall be declared ratably in proportion to the respective amounts
    of dividends accumulated and unpaid on the Series F Preferred Stock and the
    Series G Preferred Stock and accumulated and unpaid on such F Parity
    Securities. In addition to the 15% per annum quarterly dividend payable on
    the Series F Preferred Stock, the shares of Series F Preferred Stock shall
    be entitled to receive the amount of any cash or non-cash dividends or
    distributions declared and paid on the shares of Common Stock, as if the
    shares of Series F Preferred Stock had been converted immediately prior to
    the record date for the payment of such dividend or distribution.

        (e) SERIES G PREFERRED STOCK. The holders of Series G Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to $0.35 plus all unpaid
    dividends accrued on such shares of Series G Preferred Stock, on each
    outstanding share of Series G Preferred Stock (as adjusted for any stock
    dividends, combinations, splits and the like with respect to such shares),
    payable on March 31, June 30, September 30 and December 31 of each year,
    when and as declared by the Board of Directors out of the funds legally
    available for that purpose. Such dividends shall be cumulative from the date
    of issuance of the Series G Preferred Stock, whether or not earned, whether
    or not funds of the Corporation are legally available for the payment of
    dividends and whether or not declared by the Board of Directors, but such
    dividends shall be payable only when, as, and if declared by the Board of
    Directors. So long as any shares of Series G Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    B Preferred Stock, Series C Preferred Stock, Series D Preferred Stock,
    Series H Preferred Stock, Series I Preferred Stock, Common Stock or any
    other class or series of capital stock of the Corporation authorized or
    issued after the Effective Time, the terms of which do not expressly provide
    that it ranks senior to or on a parity with the Series G Preferred Stock as
    to dividends (the "G Junior Securities"), nor shall any shares of Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    H Preferred Stock, Series I Preferred Stock, Common Stock or any other class
    or series of G Junior Securities be purchased, redeemed or otherwise
    acquired for value by the Corporation (except for acquisitions of Common
    Stock by the Corporation pursuant to agreements which permit the Corporation
    to repurchase such shares upon termination of services to the Corporation,
    in exercise of the Corporation's right of first refusal upon a proposed
    transfer, for payments of cash in lieu of fractional shares pursuant to
    Section (4)(n) below, or an exchange of shares of Series B Preferred Stock
    for shares of Series H Preferred Stock and an exchange of shares of Series D
    Preferred Stock for shares of Series I Preferred Stock in accordance with a
    Recapitalization Agreement) until all dividends set forth in this Section
    (1)(e) on the Series G Preferred Stock shall have been paid or declared and
    set apart. So long as any shares of Series G Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    F Preferred Stock or any other class or series of capital stock of the
    Corporation authorized and issued after the Effective Time, the terms of
    which expressly provide that it will rank on a parity with the Series G
    Preferred Stock as to dividends (the "G Parity Securities"), nor shall any
    shares of Series F Preferred Stock or any other class or series of G Parity
    Securities be purchased, redeemed or otherwise acquired for value

                                       7
<Page>

    by the Corporation (except for payments of cash in lieu of fractional shares
    pursuant to Section (4)(n) below) until all dividends set forth in this
    Section (1)(e) on the Series G Preferred Stock shall have been paid or
    declared and set apart, except if at any time the Corporation pays less than
    the total amount of dividends then accrued with respect to the Series G
    Preferred Stock, the Series F Preferred Stock and any other G Parity
    Securities, such payment shall be distributed ratably among the holders of
    the Series F Preferred Stock, the Series G Preferred Stock and each other
    class or series of G Parity Securities entitled to receive such dividends
    based upon the aggregate accrued but unpaid dividends on such shares held by
    each holder. When dividends are not paid in full or consideration sufficient
    for such payment is not set apart as aforesaid, all dividends declared upon
    the Series G Preferred Stock, the Series F Preferred Stock and any other
    class or series of G Parity Securities shall be declared ratably in
    proportion to the respective amounts of dividends accumulated and unpaid on
    the Series F Preferred Stock and the Series G Preferred Stock and
    accumulated and unpaid on such G Parity Securities. In addition to the 15%
    per annum quarterly dividend payable on the Series G Preferred Stock, the
    shares of Series G Preferred Stock shall be entitled to receive the amount
    of any cash or non-cash dividends or distributions declared and paid on the
    shares of Common Stock, as if the shares of Series G Preferred Stock had
    been converted immediately prior to the record date for the payment of such
    dividend or distribution.

        (f) SERIES H PREFERRED STOCK. The holders of Series H Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to $1.52 plus the sum of (i) all
    unpaid dividends accrued on each share of Series H Preferred Stock from and
    including the date of issuance of such share of Series H Preferred Stock and
    (ii) all unpaid dividends accrued on the share of Series B Preferred Stock
    exchanged for such share of Series H Preferred Stock in accordance with the
    Recapitalization Agreement to (but excluding) the date of such exchange
    (such dividends of this clause (ii), the "Series H Roll-Over Amount"), on
    each outstanding share of Series H Preferred Stock (as adjusted for any
    stock dividends, combinations, splits and the like with respect to such
    shares), when and as declared by the Board of Directors out of the funds
    legally available for that purpose. Such dividends shall be cumulative from
    the date of issuance of the Series H Preferred Stock, whether or not earned,
    whether or not funds of the Corporation are legally available for the
    payment of dividends and whether or not declared by the Board of Directors,
    but such dividends shall be payable only when, as, and if declared by the
    Board of Directors. So long as any shares of Series H Preferred Stock shall
    be outstanding, no dividend, whether in cash, stock or property, shall be
    paid or declared, nor shall any other distribution be made, on any shares of
    Series C Preferred Stock, Common Stock or any other class or series of
    capital stock of the Corporation authorized or issued after the Effective
    Time, the terms of which do not expressly provide that it ranks senior to or
    on a parity with the Series H Preferred Stock as to dividends ("H Junior
    Securities"), nor shall any shares of Series C Preferred Stock, Common Stock
    or any class or series of H Junior Securities be purchased, redeemed or
    otherwise acquired for value by the Corporation (except for acquisitions of
    Common Stock by the Corporation pursuant to agreements which permit the
    Corporation to repurchase such shares upon termination of services to the
    Corporation, in exercise of the Corporation's right of first refusal upon a
    proposed transfer, or for payments of cash in lieu of fractional shares
    pursuant to Section (4)(n) below) until all dividends set forth in this
    Section (1)(f)

                                       8
<Page>

    on the Series H Preferred Stock shall have been paid or declared and set
    apart. So long as any shares of Series H Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    B Preferred Stock, Series D Preferred Stock, Series I Preferred Stock or any
    other class or series of capital stock of the Corporation authorized and
    issued after the Effective Time, the terms of which expressly provide that
    it will rank on a parity with the Series H Preferred Stock as to dividends
    ("H Parity Securities"), nor shall any shares of Series B Preferred Stock,
    Series D Preferred Stock, Series I Preferred Stock or any other class or
    series of H Parity Securities be purchased, redeemed or otherwise acquired
    for value by the Corporation (except for exercises of the Corporation's
    right of first refusal upon a proposed transfer, for payments of cash in
    lieu of fractional shares pursuant to Section (4)(n) below, or an exchange
    of shares of Series B Preferred Stock for shares of Series H Preferred Stock
    and an exchange of shares of Series D Preferred Stock for shares of Series I
    Preferred Stock in accordance with a Recapitalization Agreement) until all
    dividends set forth in this Section (1)(f) on the Series H Preferred Stock
    shall have been paid or declared and set apart, except if at any time the
    Corporation pays less than the total amount of dividends then accrued with
    respect to the Series B Preferred Stock, the Series D Preferred Stock,
    Series H Preferred Stock, Series I Preferred Stock and any other H Parity
    Securities, such payment shall be distributed ratably among the holders of
    the Series B Preferred Stock, Series D Preferred Stock, Series H Preferred
    Stock, Series I Preferred Stock and each other class or series of H Parity
    Securities entitled to receive such dividends based upon the aggregate
    accrued but unpaid dividends on such shares held by each holder. When
    dividends are not paid in full or consideration sufficient for such payment
    is not set apart as aforesaid, all dividends declared upon the Series B
    Preferred Stock, Series D Preferred Stock, Series H Preferred Stock, Series
    I Preferred Stock and any other class or series of H Parity Securities shall
    be declared ratably in proportion to the respective amounts of dividends
    accumulated and unpaid on the Series B Preferred Stock, Series D Preferred
    Stock, Series H Preferred Stock, Series I Preferred Stock and accumulated
    and unpaid on such H Parity Securities.

        (g) SERIES I PREFERRED STOCK. The holders of Series I Preferred Stock
    shall be entitled to receive dividends in cash at the rate of fifteen
    percent (15%) per annum on an amount equal to $4.50 plus the sum of (i) all
    unpaid dividends accrued on each share of Series I Preferred Stock from and
    including the date of issuance of such share of Series I Preferred Stock and
    (ii) all unpaid dividends accrued on the share of Series D Preferred Stock
    exchanged for such share of Series I Preferred Stock in accordance with a
    Recapitalization Agreement to (but excluding) the date of such exchange
    (such dividends of this clause (ii), the "Series I Roll-Over Amount"), on
    each outstanding share of Series I Preferred Stock (as adjusted for any
    stock dividends, combinations, splits and the like with respect to such
    shares), when and as declared by the Board of Directors out of the funds
    legally available for that purpose. Such dividends shall be cumulative from
    the date of issuance of the Series I Preferred Stock, whether or not earned,
    whether or not funds of the Corporation are legally available for the
    payment of dividends and whether or not declared by the Board of Directors,
    but such dividends shall be payable only when, as, and if declared by the
    Board of Directors. So long as any shares of Series I Preferred Stock shall
    be outstanding, no dividend, whether in cash, stock or property, shall be
    paid or declared, nor shall any other distribution be made, on any shares of
    Series C Preferred

                                       9
<Page>

    Stock, Common Stock or any other class or series of capital stock of the
    Corporation authorized or issued after the Effective Time, the terms of
    which do not expressly provide that it ranks senior to or on a parity with
    the Series I Preferred Stock as to dividends ("I Junior Securities"), nor
    shall any shares of Series C Preferred Stock, Common Stock or any other
    class or series of I Junior Securities be purchased, redeemed or otherwise
    acquired for value by the Corporation (except for acquisitions of Common
    Stock by the Corporation pursuant to agreements which permit the Corporation
    to repurchase such shares upon termination of services to the Corporation,
    in exercise of the Corporation's right of first refusal upon a proposed
    transfer, or for payments of cash in lieu of fractional shares pursuant to
    Section (4)(n) below) until all dividends set forth in this Section (1)(g)
    on the Series I Preferred Stock shall have been paid or declared and set
    apart. So long as any shares of Series I Preferred Stock shall be
    outstanding, no dividend, whether in cash or property, shall be paid or
    declared, nor shall any other distribution be made, on any shares of Series
    B Preferred Stock, Series D Preferred Stock, Series H Preferred Stock or any
    other class or series of capital stock of the Corporation authorized and
    issued after the Effective Time, the terms of which expressly provide that
    it will rank on a parity with the Series I Preferred Stock as to dividends
    ("I Parity Securities"), nor shall any shares of Series B Preferred Stock,
    Series D Preferred Stock, Series H Preferred Stock or any other class or
    series of I Parity Securities be purchased, redeemed or otherwise acquired
    for value by the Corporation (except for exercises of the Corporation's
    right of first refusal upon a proposed transfer, for payments of cash in
    lieu of fractional shares pursuant to Section (4)(n) below, or an exchange
    of shares of Series B Preferred Stock for shares of Series H Preferred Stock
    and an exchange of shares of Series D Preferred Stock for shares of Series I
    Preferred Stock in accordance with a Recapitalization Agreement) until all
    dividends set forth in this Section (1)(g) on the Series I Preferred Stock
    shall have been paid or declared and set apart, except if at any time the
    Corporation pays less than the total amount of dividends then accrued with
    respect to the Series B Preferred Stock, the Series D Preferred Stock,
    Series H Preferred Stock, Series I Preferred Stock and any other I Parity
    Securities, such payment shall be distributed ratably among the holders of
    the Series B Preferred Stock, Series D Preferred Stock, Series H Preferred
    Stock, Series I Preferred Stock and each other class or series of I Parity
    Securities entitled to receive such dividends based upon the aggregate
    accrued but unpaid dividends on such shares held by each holder. When
    dividends are not paid in full or consideration sufficient for such payment
    is not set apart as aforesaid, all dividends declared upon the Series B
    Preferred Stock, Series D Preferred Stock, Series H Preferred Stock, Series
    I Preferred Stock and any other class or series of I Parity Securities shall
    be declared ratably in proportion to the respective amounts of dividends
    accumulated and unpaid on the Series B Preferred Stock, Series D Preferred
    Stock, Series H Preferred Stock, Series I Preferred Stock and accumulated
    and unpaid on such I Parity Securities.

        (2) Liquidation Rights.

        (a) SERIES G PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and before any distribution or payment shall
    be made to the holders of Series B Preferred Stock, Series C Preferred
    Stock, Series H Preferred Stock or Common Stock, the holders of Series G
    Preferred Stock shall be entitled to be paid out of the assets of the
    Corporation an amount equal to the greater of (i) the sum of (a) $0.35 per
    share of

                                       10
<Page>

    Series G Preferred Stock (as adjusted for any stock dividends, combinations,
    splits and the like with respect to such shares) plus (b) an amount equal to
    all unpaid dividends accrued on such shares of Series G Preferred Stock to
    the date of payment of such preference, whether or not earned, whether or
    not funds of the Corporation are legally available for the payment of
    dividends and whether or not such dividends have been declared by the Board
    of Directors; or (ii) the amount the holders of Series G Preferred Stock
    would have received upon liquidation, dissolution or winding up of the
    Corporation had such shares of Series G Preferred Stock and all shares of
    Series D Preferred Stock, Series F Preferred Stock and Series I Preferred
    Stock been converted to Common Stock immediately prior to such liquidation,
    dissolution or winding up (such greater amount, the "Series G Liquidation
    Preference"), for each share of Series G Preferred Stock held by them. If
    the assets of the Corporation shall be insufficient to make payment in full
    to all holders of Series G Preferred Stock, Series F Preferred Stock, Series
    D Preferred Stock and Series I Preferred Stock of the liquidation preference
    set forth in Sections (2)(a) through (d), inclusive, then such assets shall
    be distributed among the holders of Series G Preferred Stock, Series F
    Preferred Stock, Series D Preferred Stock and Series I Preferred Stock at
    the time outstanding ratably in proportion to the full amounts to which they
    would otherwise be respectively entitled.

        (b) SERIES F PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and before any distribution or payment shall
    be made to the holders of Series B Preferred Stock, Series C Preferred
    Stock, Series H Preferred Stock or Common Stock, the holders of Series F
    Preferred Stock shall be entitled to be paid out of the assets of the
    Corporation an amount equal to the greater of (i) the sum of (a) the
    applicable Purchase Price per share of Series F Preferred Stock (as adjusted
    for any stock dividends, combinations, splits and the like with respect to
    such shares) plus (b) an amount equal to all unpaid dividends accrued on
    such shares of Series F Preferred Stock to the date of payment of such
    preference, whether or not earned, whether or not funds of the Corporation
    are legally available for the payment of dividends and whether or not such
    dividends have been declared by the Board of Directors; or (ii) the amount
    the holders of Series F Preferred Stock would have received upon
    liquidation, dissolution or winding up of the Corporation had such shares of
    Series F Preferred Stock and all shares of Series D Preferred Stock, Series
    G Preferred Stock and Series I Preferred Stock been converted to Common
    Stock immediately prior to such liquidation, dissolution or winding up (such
    greater amount, the "Series F Liquidation Preference"), for each share of
    Series F Preferred Stock held by them. If the assets of the Corporation
    shall be insufficient to make payment in full to all holders of Series F
    Preferred Stock, Series G Preferred Stock, Series D Preferred Stock and
    Series I Preferred Stock of the liquidation preference set forth in Sections
    (2)(a) through (d), inclusive, then such assets shall be distributed among
    the holders of Series F Preferred Stock, Series G Preferred Stock, Series D
    Preferred Stock and Series I Preferred Stock at the time outstanding ratably
    in proportion to the full amounts to which they would otherwise be
    respectively entitled.

        (c) SERIES D PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and before any distribution or payment shall
    be made to the holders of Series B Preferred Stock, Series C Preferred
    Stock, Series H Preferred Stock or Common Stock, the holders of Series D
    Preferred Stock shall be entitled to be paid out of the assets

                                       11
<Page>

    of the Corporation an amount equal to the greater of (i) the sum of (a)
    $4.50 per share of Series D Preferred Stock (as adjusted for any stock
    dividends, combinations, splits and the like with respect to such shares)
    plus (b) an amount equal to all unpaid dividends accrued on such shares of
    Series D Preferred Stock to the date of payment of such preference, whether
    or not earned, whether or not funds of the Corporation are legally available
    for the payment of dividends and whether or not such dividends have been
    declared by the Board of Directors; or (ii) the amount the holders of Series
    D Preferred Stock would have received upon liquidation, dissolution or
    winding up of the Corporation had such shares of Series D Preferred Stock
    and all shares of Series F Preferred Stock, Series G Preferred Stock and
    Series I Preferred Stock been converted to Common Stock immediately prior to
    such liquidation, dissolution or winding up (such greater amount the "Series
    D Liquidation Preference"), for each share of Series D Preferred Stock held
    by them. If the assets of the Corporation shall be insufficient to make
    payment in full to all holders of Series F Preferred Stock, Series G
    Preferred Stock, Series D Preferred Stock and Series I Preferred Stock of
    the liquidation preference set forth in Sections (2)(a) through (d)
    inclusive, then such assets shall be distributed among the holders of Series
    F Preferred Stock, Series G Preferred Stock, Series D Preferred Stock and
    Series I Preferred Stock at the time outstanding ratably in proportion to
    the full amounts to which they would otherwise be respectively entitled.

        (d) SERIES I PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and before any distribution or payment shall
    be made to the holders of Series B Preferred Stock, Series C Preferred
    Stock, Series H Preferred Stock or Common Stock, the holders of Series I
    Preferred Stock shall be entitled to be paid out of the assets of the
    Corporation an amount equal to the greater of (i) the sum of $4.50 per share
    of Series I Preferred Stock (as adjusted for any stock dividends,
    combinations, splits and the like with respect to such shares) plus (b) the
    sum of (x) the Series I Roll-Over Amount (as adjusted for any stock
    dividends, combinations, splits and the like with respect to such shares)
    and (y) an amount equal to all unpaid dividends accrued on such shares of
    Series I Preferred Stock to the date of payment of such preference, whether
    or not earned, whether or not funds of the Corporation are legally available
    for the payment of dividends and whether or not such dividends have been
    declared by the Board of Directors; or (ii) the amount the holders of Series
    I Preferred Stock would have received upon liquidation, dissolution or
    winding up of the Corporation had such shares of Series I Preferred Stock
    and all shares of Series F Preferred Stock, Series G Preferred Stock and
    Series D Preferred Stock been converted to Common Stock immediately prior to
    such liquidation, dissolution or winding up (such greater amount the "Series
    I Liquidation Preference"), for each share of Series I Preferred Stock held
    by them. If the assets of the Corporation shall be insufficient to make
    payment in full to all holders of Series F Preferred Stock, Series G
    Preferred Stock, Series D Preferred Stock and Series I Preferred Stock of
    the liquidation preference set forth in Sections (2)(a) through (d)
    inclusive, then such assets shall be distributed among the holders of Series
    F Preferred Stock, Series G Preferred Stock, Series D Preferred Stock and
    Series I Preferred Stock at the time outstanding ratably in proportion to
    the full amounts to which they would otherwise be respectively entitled.

                                       12
<Page>

        (e) SERIES B PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and after the payment of the full liquidation
    preference of the Series G Preferred Stock as set forth in Section (2)(a)
    above, the Series F Preferred Stock as set forth in Section (2)(b) above,
    the Series D Preferred Stock as set forth in Section (2)(c) above, and the
    Series I Preferred Stock as set forth in Section (2)(d) above, and before
    any distribution or payment shall be made to the holders of Series C
    Preferred Stock or Common Stock, the holders of Series B Preferred Stock
    shall be entitled to be paid out of the assets of the Corporation an amount
    equal to the sum of (i) $1.52 for each share of Series B Preferred Stock
    held by them (as adjusted for any stock dividends, combinations, splits and
    the like with respect to such shares) plus (ii) an amount equal to all
    unpaid dividends accrued on such shares of Series B Preferred Stock to the
    date of payment of such preference, whether or not earned, whether or not
    funds of the Corporation are legally available for the payment of dividends
    and whether or not such dividends have been declared by the Board of
    Directors (the "Series B Liquidation Preference"), for each share of Series
    B Preferred Stock held by them. If the remaining assets of the Corporation
    shall be insufficient to make payment in full to all holders of Series B
    Preferred Stock and Series H Preferred Stock of the liquidation preferences
    set forth in Sections (2)(e) through (f) inclusive, then such remaining
    assets shall be distributed among the holders of Series B Preferred Stock
    and Series H Preferred Stock at the time outstanding ratably in proportion
    to the full amounts to which they would otherwise be respectively entitled.

        (f) SERIES H PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and after the payment of the full liquidation
    preference of the Series G Preferred Stock as set forth in Section (2)(a)
    above, the Series F Preferred Stock as set forth in Section (2)(b) above,
    the Series D Preferred Stock as set forth in Section (2)(c) above, and the
    Series I Preferred Stock as set forth in Section (2)(d) above, and before
    any distribution or payment shall be made to the holders of Series C
    Preferred Stock or Common Stock, the holders of Series H Preferred Stock
    shall be entitled to be paid out of the assets of the Corporation an amount
    equal to the sum of (i) $1.52 per share of Series H Preferred Stock held by
    them (as adjusted for any stock dividends, combinations, splits and the like
    with respect to such shares) plus (ii) an amount equal to the sum of (x) the
    Series H Roll-Over Amount (as adjusted for any stock dividends,
    combinations, splits and the like with respect to such shares) and (y) all
    unpaid dividends accrued on such shares of Series H Preferred Stock to the
    date of payment of such preference, whether or not earned, whether or not
    funds of the Corporation are legally available for the payment of dividends
    and whether or not such dividends have been declared by the Board of
    Directors (the "Series H Liquidation Preference"), for each share of Series
    H Preferred Stock held by them. If the remaining assets of the Corporation
    shall be insufficient to make payment in full to all holders of Series H
    Preferred Stock and Series B Preferred Stock of the liquidation preferences
    set forth in Sections (2)(e) through (f), inclusive, then such remaining
    assets shall be distributed among the holders of Series H Preferred Stock
    and Series B Preferred Stock at the time outstanding ratably in proportion
    to the full amounts to which they would otherwise be respectively entitled.

        (g) SERIES C PREFERRED STOCK. Upon any liquidation, dissolution, or
    winding up of the Corporation, and after the payment of the full liquidation
    preference of the Series

                                       13
<Page>

    G Preferred Stock as set forth in Section (2)(a) above, the Series F
    Preferred Stock as set forth in Section (2)(b) above, the Series D Preferred
    Stock as set forth in Section (2)(c) above, the Series I Preferred Stock as
    set forth in Section (2)(d) above, the Series B Preferred Stock as set forth
    in Section (2)(e) above, and the Series H Preferred Stock as set forth in
    Section (2)(f) above and before any distribution or payment shall be made to
    the holders of Common Stock, the holders of Series C Preferred Stock shall
    be entitled to be paid out of the assets of the Corporation an amount equal
    to the sum of (i) $1.52 per share of Series C Preferred Stock (as adjusted
    for any stock dividends, combinations, splits and the like with respect to
    such shares), plus (ii) an amount equal to all declared and unpaid dividends
    for each share of Series C Preferred Stock held by them (the "Series C
    Liquidation Preference"). If the remaining assets of the Corporation shall
    be insufficient to make payment in full to all holders of Series C Preferred
    Stock of the liquidation preference set forth in this Section (2)(g), then
    such remaining assets shall be distributed among the holders of Series C
    Preferred Stock at the time outstanding ratably in proportion to the full
    amounts to which they would otherwise be respectively entitled.

        (h) COMMON STOCK. Upon any liquidation, dissolution, or winding up of
    the Corporation, and after the payment in full of the Series G Liquidation
    Preference, Series F Liquidation Preference, Series D Liquidation
    Preference, the Series I Liquidation Preference, the Series B Liquidation
    Preference, the Series H Liquidation Preference, and the Series C
    Liquidation Preference, then the remaining assets of the Corporation legally
    available for distribution, if any, shall be distributed ratably to the
    holders of the Common Stock.

        (i) DEEMED LIQUIDATIONS.

                (i) At the election of the holders of a majority of the voting
        power of the outstanding shares of the Series B Preferred Stock, Series
        C Preferred Stock, Series D Preferred Stock, Series F Preferred Stock,
        Series G Preferred Stock, Series H Preferred Stock and Series I
        Preferred Stock, voting together as a single class, the following events
        will be deemed a liquidation under this section: (i) consolidation,
        reorganization, share exchange, recapitalization, business combination,
        merger or similar transaction involving the Corporation in which the
        stockholders of the Corporation immediately prior to such transaction in
        the aggregate cease to own at least 50% of the voting securities of the
        entity surviving or resulting from such transaction (or the ultimate
        parent thereof), or any transaction or series of related transactions in
        which in excess of 50% of the Corporation's voting power is transferred
        (in any case, an "Acquisition"); and (ii) the sale, lease, transfer or
        other disposition of all or substantially all of the assets of the
        Corporation (an "Asset Transfer").

                (ii) Notwithstanding the foregoing, the Corporation shall not be
        obligated to make any payment of the applicable liquidation preferences
        in cash pursuant to this Section (2)(i) if such payment or the existence
        of this deemed liquidation provision would violate the terms of the
        Indenture, dated as of June 23, 1998, by and between the Corporation and
        Norwest Bank Minnesota, National Association (as trustee), as amended
        (the "Indenture"), until 91 days after the date on which

                                       14
<Page>

        the Senior Notes due 2008 issued by the Corporation pursuant to such
        Indenture (the "Senior Notes") mature. If the Corporation is unable to
        pay the liquidation preferences in cash as set forth in this section,
        the holders of a majority of the voting power of the then outstanding
        shares of Series B Preferred Stock, Series C Preferred Stock, Series D
        Preferred Stock, Series F Preferred Stock, Series G Preferred Stock,
        Series H Preferred Stock and Series I Preferred Stock, voting together
        as a single class, may elect to receive shares of Common Stock with a
        fair market value (as determined in accordance with Section (2)(k))
        equal to the respective liquidation preferences of such shares.

        (j) PAYMENTS IN PROPERTY. Whenever the distribution provided for in this
    Section (2) shall be payable in securities or other property other than
    cash, the value of that distribution shall be the fair market value of those
    securities or other property.

        (k) DETERMINATIONS OF FAIR MARKET VALUE. Whenever a determination of
    fair market value is required under this Restated Certificate of
    Incorporation, the fair market value shall be determined based upon the
    price that would be paid by a willing buyer of the assets or shares at
    issue, in a sale process designed to attract all possible participants and
    to maximize value. The determination of fair market value shall be made (i)
    by the Board of Directors or (ii) if the holders of a majority of the voting
    power of the outstanding shares of Series F Preferred Stock and the Series G
    Preferred Stock, voting together as a single class, object to such
    determination by the Board of Directors, by a nationally recognized
    investment banking firm mutually agreeable to the Corporation and the
    holders of a majority of the voting power of the outstanding shares of
    Series F Preferred Stock and the Series G Preferred Stock, voting together
    as a single class. The fees and expenses of such investment banking firm
    shall be paid by the Corporation.

        (3) Voting Rights.

        (a) SERIES B, SERIES C, SERIES D, SERIES F, SERIES G, SERIES H AND
    SERIES I PREFERRED STOCK. The holders of Series B Preferred Stock shall be
    entitled to cast one vote for each share of Series B Preferred Stock held by
    them on an as-converted basis, the holders of Series C Preferred Stock shall
    be entitled to cast one vote for each share of Series C Preferred Stock held
    by them on an as-converted basis, the holders of Series D Preferred Stock
    shall be entitled to cast one vote for each share of Series D Preferred
    Stock held by them on an as-converted basis, the holders of Series F
    Preferred Stock shall be entitled to cast one vote for each share of Series
    F Preferred Stock held by them on an as-converted basis, the holders of
    Series G Preferred Stock shall be entitled to cast one vote for each share
    of Series G Preferred Stock held by them on an as-converted basis, the
    holders of Series H Preferred Stock shall be entitled to cast one vote for
    each share of Series H Preferred Stock held by them on an as-converted
    basis, and the holders of Series I Preferred Stock shall be entitled to cast
    one vote for each share of Series I Preferred Stock held by them on an
    as-converted basis. Such votes shall be cast together with those cast by the
    holders of Common Stock and not as a separate class, except as otherwise
    provided herein or required by applicable law. The Series B Preferred Stock,
    the Series C Preferred Stock, the Series D Preferred Stock, the Series F
    Preferred Stock, the Series

                                       15
<Page>

    G Preferred Stock, the Series H Preferred Stock, and Series I Preferred
    Stock shall not have cumulative voting rights.

        (b) Restrictions and Limitations.

                  (i) So long as the outstanding shares of Series F Preferred
            Stock represent at least five percent (5%) or more of the
            outstanding shares of Common Stock of the Corporation (on an
            as-converted to Common Stock basis), the approval by the vote or
            written consent of the holders of at least seventy-five percent
            (75%) of the then outstanding shares of Series F Preferred Stock
            shall be necessary for effecting or validating the following actions
            with respect to the Corporation:

                        (A) Any amendment, alteration, or repeal of any
                  provision of this Restated Certificate of Incorporation or
                  Bylaws of the Corporation (including the filing of a
                  Certificate of Designation), each as amended from time to
                  time, that adversely affects the voting powers, preferences or
                  other special rights or privileges, qualifications,
                  limitations, or restrictions of the Series F Preferred Stock;

                        (B) Any authorization, creation, or increase in the
                  authorized number of any class or series of capital stock
                  ranking senior to or on parity with the Series F Preferred
                  Stock as to dividends, voting rights or liquidation, or any
                  issuance of any shares of such class or series of capital
                  stock (or any securities convertible into, or exchangeable or
                  exerciseable for such shares);

                        (C) Any payment of any cash or non-cash dividends or
                  other distributions with respect to its capital stock;

                        (D) Any reclassification, combination, split,
                  subdivision, redemption, repurchase or other acquisition of
                  any shares of capital stock (except for acquisitions of Common
                  Stock by the Corporation pursuant to agreements which permit
                  the Corporation to repurchase such shares upon the termination
                  of services to the Corporation or in exercise of the
                  Corporation's right of first refusal upon a proposed
                  transfer);

                        (E) Any agreement by the Corporation or its stockholders
                  regarding an Acquisition or an Asset Transfer (as defined in
                  Section (2)(i));

                        (F) Any acquisition of assets or securities of any other
                  person or entity, except for acquisitions involving cash with
                  an aggregate value of less than five percent (5%) of the
                  Corporation's assets for any single acquisition or series of
                  related transactions;

                        (G) Any joint venture or similar profit sharing
                  arrangement involving material assets or the payment or
                  receipt of more than five percent (5%) of the Corporation's
                  assets;

                                       16
<Page>

                        (H) Any liquidation, dissolution or winding up of the
                  Corporation; or

                        (I) An amendment, alteration, or repeal of this Section
                  (3)(b)(i).

                  (ii) So long as the outstanding shares of Series G Preferred
            Stock represent at least five percent (5%) or more of the
            outstanding shares of Common Stock of the Corporation (on an
            as-converted to Common Stock basis), the approval by the vote or
            written consent of the holders of at least seventy-five percent
            (75%) of the then outstanding shares of Series G Preferred Stock
            shall be necessary for effecting or validating the following actions
            with respect to the Corporation:

                        (A) Any amendment, alteration, or repeal of any
                  provision of this Restated Certificate of Incorporation or
                  Bylaws of the Corporation (including the filing of a
                  Certificate of Designation), each as amended from time to
                  time, that adversely affects the voting powers, preferences or
                  other special rights or privileges, qualifications,
                  limitations, or restrictions of the Series G Preferred Stock;

                        (B) Any authorization, creation, or increase in the
                  authorized number of any class or series of capital stock
                  ranking senior to or on parity with the Series G Preferred
                  Stock as to dividends, voting rights or liquidation, or any
                  issuance of any shares of such class or series of capital
                  stock (or any securities convertible into, or exchangeable or
                  exerciseable for such shares);

                        (C) Any payment of any cash or non-cash dividends or
                  other distributions with respect to its capital stock;

                        (D) Any reclassification, combination, split,
                  subdivision, redemption, repurchase or other acquisition of
                  any shares of capital stock (except for acquisitions of Common
                  Stock by the Corporation pursuant to agreements which permit
                  the Corporation to repurchase such shares upon the termination
                  of services to the Corporation or in exercise of the
                  Corporation's right of first refusal upon a proposed
                  transfer);

                        (E) Any agreement by the Corporation or its stockholders
                  regarding an Acquisition or an Asset Transfer (as defined in
                  Section (2)(i));

                        (F) Any acquisition of assets or securities of any other
                  person or entity, except for acquisitions involving cash with
                  an aggregate value of less than five percent (5%) of the
                  Corporation's assets for any single acquisition or series of
                  related transactions;

                                       17
<Page>

                        (G) Any joint venture or similar profit sharing
                  arrangement involving material assets or the payment or
                  receipt of more than five percent (5%) of the Corporation's
                  assets;

                        (H) Any liquidation, dissolution or winding up of the
                  Corporation; or

                        (I) An amendment, alteration, or repeal of this Section
                  (3)(b)(ii).

        (c) Election of Board of Directors.

                (i) For so long as at least 6,666,667 shares of Series F
        Preferred Stock remain outstanding (subject to adjustment for any stock
        split, reverse stock split and the like), the holders of Series F
        Preferred Stock, voting as a separate class, shall be entitled to elect
        that number of directors to the Corporation's Board of Directors equal
        to (A) the authorized size of the Corporation's Board of Directors,
        multiplied by (B) (I) the total number of shares of the Corporation's
        Common Stock represented by the shares of Series F Preferred Stock then
        outstanding (on an as-converted basis), divided by (II) the total number
        of shares of the Corporation's Common Stock then outstanding (assuming
        conversion of all Preferred Stock then outstanding), rounding up so that
        the nominees of the holders of Series F Preferred Stock will not
        represent less than such proportionate interest in (B) above, at each
        meeting or pursuant to each consent of the Corporation's stockholders
        for the election of directors; provided, however, that for purposes of
        this Section (3)(c)(i) only, the calculation of the total number of
        shares outstanding shall exclude any equity securities issued by the
        Corporation after August 5, 1999 (the "Series F Original Issue Date")
        (other than the shares of Series F Preferred Stock issued after such
        date, shares of Series G Preferred Stock, shares of Series H Preferred
        Stock, shares of Series I Preferred Stock, and any shares of Common
        Stock issued upon conversion of any of the foregoing) if at such time
        the outstanding shares of Series F Preferred Stock represent thirty
        percent (30%) or more of the outstanding Common Stock of the Corporation
        (on an as-converted to Common Stock basis). Only the holders of the
        Series F Preferred Stock shall be entitled to remove from office such
        directors without cause, and only the holders of the Series F Preferred
        Stock and the directors elected by the holders of the Series F Preferred
        Stock shall be entitled to fill any vacancy caused by the resignation,
        death or removal of such directors.

                (ii) For so long as at least 42,379,182 shares of Series G
        Preferred Stock remain outstanding (subject to adjustment for any stock
        split, reverse stock split and the like), the holders of Series G
        Preferred Stock, voting as a separate class, shall be entitled to elect
        that number of directors to the Corporation's Board of Directors equal
        to (A) the authorized size of the Corporation's Board of Directors,
        multiplied by (B) (I) the total number of shares of the Corporation's
        Common Stock represented by the shares of Series G Preferred Stock then
        outstanding (on an as-converted basis), divided by (II) the total number
        of shares of the Corporation's Common Stock then outstanding (assuming
        conversion of all

                                       18
<Page>

        Preferred Stock then outstanding), rounding up so that the nominees of
        the holders of Series G Preferred Stock will not represent less than
        such proportionate interest in (B) above (provided that no rounding up
        will occur if as a result of rounding up for the Series F Preferred
        Stock there would be more than one director more than the proportionate
        interest represented by the holders of the Series F Preferred Stock and
        the Series G Preferred Stock together), at each meeting or pursuant to
        each consent of the Corporation's stockholders for the election of
        directors; provided, however, that for purposes of this Section
        (3)(c)(ii) only, the calculation of the total number of shares
        outstanding shall exclude any equity securities issued by the
        Corporation after the date of this Restated Certificate of Incorporation
        (other than shares of Series H Preferred Stock, shares of Series I
        Preferred Stock, and any shares of Common Stock issued upon conversion
        of any of the foregoing) if at such time the outstanding shares of
        Series G Preferred Stock represent thirty percent (30%) or more of the
        outstanding Common Stock of the Corporation (on an as-converted to
        Common Stock basis). Only the holders of the Series G Preferred Stock
        shall be entitled to remove from office such directors without cause,
        and only the holders of the Series G Preferred Stock and the directors
        elected by the holders of the Series G Preferred Stock shall be entitled
        to fill any vacancy caused by the resignation, death or removal of such
        directors.

                (iii) For so long as at least 15,000,000 shares of Series B
        Preferred Stock, Series C Preferred Stock, Series D Preferred Stock,
        Series H Preferred Stock and Series I Preferred Stock remain outstanding
        (subject to adjustment for any stock split, reverse stock split and the
        like), the holders of Series B Preferred Stock, Series C Preferred
        Stock, Series D Preferred Stock, Series H Preferred Stock and Series I
        Preferred Stock, voting together as a single class, shall be entitled to
        elect one (1) member of the Board of Directors at each meeting or
        pursuant to each consent of the Corporation's stockholders for the
        election of directors, and only the holders of the Series B Preferred
        Stock, Series C Preferred Stock, Series D Preferred Stock, Series H
        Preferred Stock and Series I Preferred Stock, voting together a single
        class, shall be entitled to remove from office such director without
        cause, and only the holders of the Series B Preferred Stock, Series C
        Preferred Stock, Series D Preferred Stock, Series H Preferred Stock and
        Series I Preferred Stock and the director elected by such holders of the
        Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
        Stock, Series H Preferred Stock and Series I Preferred Stock shall be
        entitled to fill any vacancy caused by the resignation, death or removal
        of such director.

                (iv) For so long as the conditions set forth in Sections
        (3)(c)(i) through (iii) are satisfied, the holders of Common Stock,
        voting as a separate class, shall be entitled to elect one (1) member of
        senior management of the Corporation to the Board of Directors at each
        meeting or pursuant to each consent of the Corporation's stockholders
        for the election of directors, and only the holders of the Common Stock
        shall be entitled to remove from office such director without cause, and
        only the holders of Common Stock and the director elected by such

                                       19
<Page>

        holders of Common Stock shall be entitled to fill any vacancy caused by
        the resignation, death or removal of such director.

                (v) Except as provided in Sections (3)(c)(i) through (iv) above,
        the holders of Common Stock and Preferred Stock, voting together as a
        single class, shall be entitled to elect all members of the Board of
        Directors.

        (4) CONVERSION RIGHTS. The holders of the Series B Preferred Stock,
    Series C Preferred Stock, Series D Preferred Stock, Series F Preferred
    Stock, Series G Preferred Stock, Series H Preferred Stock and Series I
    Preferred Stock shall have the following rights with respect to the
    conversion of the Series B Preferred Stock, Series C Preferred Stock, Series
    D Preferred Stock, Series F Preferred Stock, Series G Preferred Stock,
    Series H Preferred Stock and Series I Preferred Stock into shares of Common
    Stock (the "Conversion Rights"):

        (a) OPTIONAL CONVERSION. Subject to and in compliance with the
    provisions of this Section (4), any shares of Series B Preferred Stock,
    Series C Preferred Stock, Series D Preferred Stock, Series F Preferred
    Stock, Series G Preferred Stock, Series H Preferred Stock and Series I
    Preferred Stock may, at the option of the holder, be converted at any time
    into fully paid and nonassessable shares of Common Stock. The number of
    shares of Common Stock to which a holder of Series B Preferred Stock, Series
    C Preferred Stock, Series D Preferred Stock, Series F Preferred Stock,
    Series G Preferred Stock, Series H Preferred Stock or Series I Preferred
    Stock shall be entitled upon conversion shall be the product obtained by
    multiplying the applicable Preferred Stock Rate then in effect (determined
    as provided in Section (4)(c)) by the number of shares of Series B Preferred
    Stock, Series C Preferred Stock, Series D Preferred Stock, Series F
    Preferred Stock, Series G Preferred Stock, Series H Preferred Stock or
    Series I Preferred Stock being converted by such holder.

        (b) AUTOMATIC CONVERSION. (i) Subject to and in compliance with the
    provisions of this Section (4), all outstanding shares of Series B Preferred
    Stock, Series C Preferred Stock, Series D Preferred Stock, Series F
    Preferred Stock, Series G Preferred Stock, Series H Preferred Stock and
    Series I Preferred Stock shall be automatically converted into shares of
    Common Stock immediately prior to the closing of a firmly underwritten
    public offering pursuant to an effective registration statement under the
    Securities Act of 1933, as amended, covering the offer and sale of Common
    Stock for the account of the Corporation (such offering, an "IPO") in which
    (x) the gross proceeds to the Corporation (before underwriting discounts,
    commissions and fees) are at least $60,000,000 and (y) the per share price
    to the public is at least $1.05 (subject to adjustment for any subsequent
    stock split, reverse stock split and the like) (such an IPO meeting the
    qualifications of clauses (x) and (y), a "Qualified Public Offering"). The
    number of shares of Common Stock to which a holder of Series B Preferred
    Stock shall be entitled upon conversion shall be the product obtained by
    multiplying the applicable Preferred Stock Rate then in effect by the number
    of shares of Series B Preferred Stock being converted by such holder. The
    number of shares of Common Stock to which a holder of Series C Preferred
    Stock shall be entitled upon conversion shall be the product obtained by
    multiplying the applicable Preferred Stock Rate then in effect by the number
    of shares of Series C

                                       20
<Page>

    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series D Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series D
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series F Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series F
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series G Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series G
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series H Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series H
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series I Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series I
    Preferred Stock being converted by such holder.

        (ii) Subject to and in compliance with the provisions of this Section
    (4), upon the written election of the holders of a majority of the voting
    power of the then outstanding shares of Series B Preferred Stock, Series C
    Preferred Stock, Series D Preferred Stock, Series F Preferred Stock, Series
    G Preferred Stock, Series H Preferred Stock and Series I Preferred Stock,
    voting together as a single class, immediately prior to the closing of an
    IPO that is not a Qualified Public Offering, all outstanding shares of
    Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
    Preferred Stock and Series I Preferred Stock shall be automatically
    converted into shares of Common Stock. The number of shares of Common Stock
    to which a holder of Series B Preferred Stock shall be entitled upon
    conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series B
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series C Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series C
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series D Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series D
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series F Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series F
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series G Preferred Stock shall be entitled
    upon conversion shall be the product obtained by multiplying the applicable
    Preferred Stock Rate then in effect by the number of shares of Series G
    Preferred Stock being converted by such holder. The number of shares of
    Common Stock to which a holder of Series H Preferred Stock shall be entitled
    upon conversion shall be the product obtained by

                                       21
<Page>

    multiplying the applicable Preferred Stock Rate then in effect by the number
    of shares of Series H Preferred Stock being converted by such holder. The
    number of shares of Common Stock to which a holder of Series I Preferred
    Stock shall be entitled upon conversion shall be the product obtained by
    multiplying the applicable Preferred Stock Rate then in effect by the number
    of shares of Series I Preferred Stock being converted by such holder.

        (c) PREFERRED STOCK. The conversion rate of the applicable series of
    Preferred Stock in effect at any time for conversion of the Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    F Preferred Stock, Series G Preferred Stock, Series H Preferred Stock or
    Series I Preferred Stock (the "Preferred Stock Rate") shall be the quotient
    obtained by dividing the Original Issue Price of the applicable series of
    Preferred Stock by the applicable Preferred Stock Price, calculated as
    provided in Section (4)(d). The "Original Issue Price" for the Series B
    Preferred Stock, Series C Preferred Stock and Series H Preferred Stock shall
    equal $1.52 per share. The "Original Issue Price" of the Series D Preferred
    Stock and Series I Preferred Stock shall equal $4.50 per share. The
    "Original Issue Price" of the Series F Preferred Stock shall equal the
    Purchase Price with respect to each share. The "Original Issue Price" of the
    Series G Preferred Stock shall equal $0.35 per share.

        (d) CONVERSION PRICE. The conversion price, as of the Effective Time (as
    defined in the second paragraph of paragraph (A) of this Article Fourth),
    shall: for the Series B Preferred Stock be $0.8468; for the Series C
    Preferred Stock be $0.8468; for the Series D Preferred Stock be $2.507; for
    the Series F Preferred Stock be $0.35; for the Series G Preferred Stock be
    $0.35, for the Series H Preferred Stock be $0.35; and for the Series I
    Preferred Stock be $0.35. All references to the Preferred Stock Price herein
    shall mean the Preferred Stock Price as applicable and as so adjusted.

        (e) MECHANICS OF CONVERSION. Each holder of Series B Preferred Stock,
    Series C Preferred Stock, Series D Preferred Stock, Series F Preferred
    Stock, Series G Preferred Stock, Series H Preferred Stock or Series I
    Preferred Stock who desires to convert the same into shares of Common Stock
    pursuant to this Section (4) shall surrender the certificate or certificates
    therefor, duly endorsed, at the office of the Corporation or any transfer
    agent for the Series B Preferred Stock, Series C Preferred Stock, Series D
    Preferred Stock, Series F Preferred Stock, Series G Preferred Stock, Series
    H Preferred Stock or Series I Preferred Stock, and shall give written notice
    to the Corporation at such office that such holder elects to convert the
    same. Such notice shall state the number of shares of Series B Preferred
    Stock, Series C Preferred Stock, Series D Preferred Stock, Series F
    Preferred Stock, Series G Preferred Stock, Series H Preferred Stock or
    Series I Preferred Stock being converted. Thereupon, the Corporation shall
    promptly issue and deliver at such office to such holder a certificate or
    certificates for the number of shares of Common Stock to which such holder
    is entitled. Such conversion shall be deemed to have been made at the close
    of business on the date of such surrender of the certificates representing
    the shares of Series B Preferred Stock, Series C Preferred Stock, Series D
    Preferred Stock, Series F Preferred Stock, Series G Preferred Stock, Series
    H Preferred Stock or Series I Preferred Stock to be converted, and the
    person entitled to receive the shares of Common Stock issuable upon such
    conversion shall be

                                       22
<Page>

    treated for all purposes as the record holder of such shares of Common Stock
    on such date.

        (f) ADJUSTMENT FOR STOCK SPLITS AND COMBINATIONS. If the Corporation
    shall at any time or from time to time after the Effective Time effect a
    subdivision of the outstanding Common Stock without a corresponding
    subdivision of the Series B Preferred Stock, Series C Preferred Stock,
    Series D Preferred Stock, Series F Preferred Stock, Series G Preferred
    Stock, Series H Preferred Stock or Series I Preferred Stock, the Preferred
    Stock Price for each series of Preferred Stock in effect immediately before
    that subdivision shall be proportionately decreased. Conversely, if the
    Corporation shall at any time or from time to time after the Effective Time
    combine the outstanding shares of Common Stock into a smaller number of
    shares without a corresponding combination of the Series B Preferred Stock,
    Series C Preferred Stock, Series D Preferred Stock, Series F Preferred
    Stock, Series G Preferred Stock, Series H Preferred Stock or Series I
    Preferred Stock, the Preferred Stock Price for each series of Preferred
    Stock in effect immediately before the combination shall be proportionately
    increased. Any adjustment under this Section (4)(f) shall become effective
    at the close of business on the date the subdivision or combination becomes
    effective.

        (g) ADJUSTMENT FOR COMMON STOCK DIVIDENDS AND DISTRIBUTIONS. If the
    Corporation at any time or from time to time makes, or fixes a record date
    for the determination of holders of Common Stock entitled to receive, a
    dividend or other distribution payable in additional shares of Common Stock,
    in each such event the Preferred Stock Price of each applicable series of
    Preferred Stock that is then in effect shall be decreased as of the time of
    such issuance or, in the event such record date is fixed, as of the close of
    business on such record date, by multiplying the Preferred Stock Price for
    each applicable series of Preferred Stock then in effect by a fraction (i)
    the numerator of which is the total number of shares of Common Stock issued
    and outstanding immediately prior to the time of such issuance or the close
    of business on such record date, and (ii) the denominator of which is the
    total number of shares of Common Stock issued and outstanding immediately
    prior to the time of such issuance or the close of business on such record
    date plus the number of shares of Common Stock issuable in payment of such
    dividend or distribution; provided, however, that if such record date is
    fixed and such dividend is not fully paid or if such distribution is not
    fully made on the date fixed therefor, the applicable Preferred Stock Price
    shall be recomputed accordingly as of the close of business on such record
    date and thereafter the applicable Preferred Stock Price shall be adjusted
    pursuant to this Section (4)(g) to reflect the actual payment of such
    dividend or distribution.

        (h) ADJUSTMENTS FOR OTHER DIVIDENDS AND DISTRIBUTIONS. If the
    Corporation at any time or from time to time makes, or fixes a record date
    for the determination of holders of Common Stock entitled to receive, a
    dividend or other distribution payable in securities of the Corporation
    other than shares of Common Stock, in each such event provision shall be
    made so that the holders of the Series B Preferred Stock, Series C Preferred
    Stock, Series D Preferred Stock, Series F Preferred Stock, Series G
    Preferred Stock, Series H Preferred Stock and Series I Preferred Stock shall
    receive upon conversion thereof, in addition to the number of shares of
    Common Stock receivable

                                       23
<Page>

    thereupon, the amount of other securities of the Corporation which they
    would have received had their Series B Preferred Stock, Series C Preferred
    Stock, Series D Preferred Stock, Series F Preferred Stock, Series G
    Preferred Stock, Series H Preferred Stock or Series I Preferred Stock been
    converted into Common Stock on the date of such event and had they
    thereafter, during the period from the date of such event to and including
    the conversion date, retained such securities receivable by them as
    aforesaid during such period, subject to all other adjustments called for
    during such period under this Section (4)(h) with respect to the rights of
    the holders of the Preferred Stock or with respect to such other securities
    by their terms.

        (i) ADJUSTMENT FOR RECLASSIFICATION, EXCHANGE AND SUBSTITUTION. If at
    any time or from time to time after the Effective Time, the Common Stock
    issuable upon the conversion of the Series B Preferred Stock, Series C
    Preferred Stock, Series D Preferred Stock, Series F Preferred Stock, Series
    G Preferred Stock, Series H Preferred Stock and Series I Preferred Stock is
    changed into the same or a different number of shares of any class or
    classes of stock, whether by recapitalization, reclassification or otherwise
    (other than an Acquisition or Asset Transfer (as defined in Section (2)(i))
    that is deemed a liquidation pursuant to Section (2)(i) and pursuant to
    which the holders of the Preferred Stock receive the applicable liquidation
    preferences therefor, or a subdivision or combination of shares or stock
    dividend or a reorganization, merger, consolidation or sale of assets
    provided for elsewhere in this Section (4)), in any such event each holder
    of Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
    Preferred Stock and Series I Preferred Stock shall have the right thereafter
    to convert such stock into the kind and amount of stock and other securities
    and property receivable upon such recapitalization, reclassification or
    other change by holders of the maximum number of shares of Common Stock into
    which such shares of Series B Preferred Stock, Series C Preferred Stock,
    Series D Preferred Stock, Series F Preferred Stock, Series G Preferred
    Stock, Series H Preferred Stock or Series I Preferred Stock could have been
    converted immediately prior to such recapitalization, reclassification or
    change, all subject to further adjustment as provided herein or with respect
    to such other securities or property by the terms thereof.

        (j) REORGANIZATIONS, MERGERS, CONSOLIDATIONS OR SALES OF ASSETS. If at
    any time or from time to time after the Effective Time, there is a capital
    reorganization of the Common Stock, merger, consolidation or sale of assets
    (other than an Acquisition or Asset Transfer (as defined in Section (2)(i))
    that is deemed a liquidation pursuant to Section (2)(i) and pursuant to
    which the holders of the Preferred Stock receive the applicable liquidation
    preferences therefor, or a recapitalization, subdivision, combination,
    reclassification, exchange or substitution of shares provided for elsewhere
    in this Section (4)), as a part of such capital reorganization, merger,
    consolidation or sale of assets, provision shall be made so that the holders
    of the Series B Preferred Stock, Series C Preferred Stock, Series D
    Preferred Stock, Series F Preferred Stock, Series G Preferred Stock, Series
    H Preferred Stock and Series I Preferred Stock shall thereafter be entitled
    to receive upon conversion of the Series B Preferred Stock, Series C
    Preferred Stock, Series D Preferred Stock, Series F Preferred Stock, Series
    G Preferred Stock, Series H Preferred Stock and Series I Preferred Stock the
    number of shares of stock

                                       24
<Page>

    or other securities or property of the Corporation or third party entity to
    which a holder of the number of shares of Common Stock deliverable upon
    conversion would have been entitled on such capital reorganization, merger,
    consolidation or sale of assets, subject to adjustment in respect of such
    stock or securities by the terms thereof. In any such case, appropriate
    adjustment shall be made in the application of the provisions of this
    Section (4) with respect to the rights of the holders of Series B Preferred
    Stock, Series C Preferred Stock, Series D Preferred Stock, Series F
    Preferred Stock, Series G Preferred Stock, Series H Preferred Stock and
    Series I Preferred Stock after the capital reorganization, merger,
    consolidation or sale of assets to the end that the provisions of this
    Section (4) (including adjustment of the Preferred Stock Price then in
    effect and the number of shares issuable upon conversion of the Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    F Preferred Stock, Series G Preferred Stock, Series H Preferred Stock and
    Series I Preferred Stock) shall be applicable after that event and be as
    nearly equivalent as practicable.

        (k) SALE OF SHARES BELOW PREFERRED STOCK PRICE.

              (i) If at any time or from time to time after the Effective Time,
        the Corporation issues or sells, or is deemed by the express provisions
        of this Section (4)(k) to have issued or sold, Additional Shares of
        Common Stock (as defined in Section (4)(k)(iv) below), other than as a
        dividend or other distribution on any class of stock as provided in
        Section (4)(g) above, and other than a subdivision or combination of
        shares of Common Stock as provided in Section (4)(f) above, for an
        Effective Price (as defined in Section (4)(k)(iv) below) less than the
        then effective Preferred Stock Price with respect to the applicable
        series of Preferred Stock, then and in each such case: (I) the then
        existing Preferred Stock Price with respect to the Series B Preferred
        Stock, Series C Preferred Stock and Series D Preferred Stock shall be
        reduced, as of the opening of business on the date of such issue or
        sale, to a price determined by multiplying the applicable existing
        Preferred Stock Price by a fraction (i) the numerator of which shall be
        (A) the number of shares of Common Stock deemed outstanding (as defined
        below) immediately prior to such issue or sale, plus (B) the number of
        shares of Common Stock which the aggregate consideration received (as
        defined in Section (4)(k)(ii) below) by the Corporation for the total
        number of Additional Shares of Common Stock so issued would purchase at
        such applicable Preferred Stock Price, and (ii) the denominator of which
        shall be the number of shares of Common Stock deemed outstanding (as
        defined below) immediately prior to such issue or sale plus the total
        number of Additional Shares of Common Stock so issued; and (II) the then
        existing Preferred Stock Price with respect to the Series F Preferred
        Stock, Series G Preferred Stock, Series H Preferred Stock and Series I
        Preferred Stock shall be reduced, as of the opening of business on the
        date of such issue or sale, to a price equal to the Effective Price. For
        the purposes of this Section (4)(k)(i), the number of shares of Common
        Stock deemed to be outstanding as of a given date shall be the sum of
        (A) the number of shares of Common Stock actually outstanding, (B) the
        number of shares of Common Stock into which the then outstanding shares
        of Series B Preferred Stock, Series C Preferred Stock, Series D
        Preferred Stock, Series F Preferred Stock, Series G Preferred Stock,

                                       25
<Page>

        Series H Preferred Stock and Series I Preferred Stock could be converted
        if fully converted on the day immediately preceding the given date, and
        (C) the number of shares of Common Stock which could be obtained through
        the exercise or conversion of all other rights, options and convertible
        securities on the day immediately preceding the given date.

              (ii) For the purpose of making any adjustment required under this
        Section (4)(k), the consideration received by the Corporation for any
        issue or sale of securities shall (A) to the extent it consists of cash,
        be computed at the net amount of cash received by the Corporation after
        deduction of any underwriting or similar commissions, compensation or
        concessions paid or allowed by the Corporation in connection with such
        issue or sale but without deduction of any expenses payable by the
        Corporation, (B) to the extent it consists of property other than cash,
        be computed at the fair value of that property as determined in good
        faith by the Board of Directors, and (C) if Additional Shares of Common
        Stock, Convertible Securities (as defined in Section (4)(k)(iii) below)
        or rights or options to purchase either Additional Shares of Common
        Stock or Convertible Securities are issued or sold together with other
        stock or securities or other assets of the Corporation for a
        consideration which covers both, be computed as the portion of the
        consideration so received that may be reasonably determined in good
        faith by the Board of Directors to be allocable to such Additional
        Shares of Common Stock, Convertible Securities or rights or options.

              (iii) For the purpose of the adjustment required under this
        Section (4)(k), if the Corporation issues or sells any rights or options
        for the purchase of, or stock or other securities convertible into,
        Additional Shares of Common Stock (such convertible stock or securities
        being herein referred to as "Convertible Securities") and if the
        Effective Price of such Additional Shares of Common Stock is less than
        the applicable Preferred Stock Price, in each case the Corporation shall
        be deemed to have issued at the time of the issuance of such rights or
        options or Convertible Securities the maximum number of Additional
        Shares of Common Stock issuable upon exercise or conversion thereof and
        to have received as consideration for the issuance of such shares an
        amount equal to the total amount of the consideration, if any, received
        by the Corporation for the issuance of such rights or options or
        Convertible Securities, plus, in the case of such rights or options, the
        minimum amounts of consideration, if any, payable to the Corporation
        upon the exercise of such rights or options, plus, in the case of
        Convertible Securities, the minimum amounts of consideration, if any,
        payable to the Corporation (other than by cancellation of liabilities or
        obligations evidenced by such Convertible Securities) upon the
        conversion thereof; provided that if in the case of Convertible
        Securities the minimum amounts of such consideration cannot be
        ascertained, but are a function of antidilution or similar protective
        clauses, the Corporation shall be deemed to have received the minimum
        amounts of consideration without reference to such clauses; provided
        further that if the minimum amount of consideration payable to the
        Corporation upon the exercise or conversion of rights, options or
        Convertible Securities is reduced over time or on the occurrence or
        non-occurrence of specified events other than by reason of

                                       26
<Page>

        antidilution adjustments, the Effective Price shall be recalculated
        using the figure to which such minimum amount of consideration is
        reduced; provided further that if the minimum amount of consideration
        payable to the Corporation upon the exercise or conversion of such
        rights, options or Convertible Securities is subsequently increased, the
        Effective Price shall be again recalculated using the increased minimum
        amount of consideration payable to the Corporation upon the exercise or
        conversion of such rights, options or Convertible Securities. No further
        adjustment of the applicable Preferred Stock Price, as adjusted upon the
        issuance of such rights, options or Convertible Securities, shall be
        made as a result of the actual issuance of Additional Shares of Common
        Stock on the exercise of any such rights or options or the conversion of
        any such Convertible Securities. If any such rights or options or the
        conversion privilege represented by any such Convertible Securities
        shall expire without having been exercised, the applicable Preferred
        Stock Price as adjusted upon the issuance of such rights, options or
        Convertible Securities shall be readjusted to the applicable Preferred
        Stock Price which would have been in effect had an adjustment been made
        on the basis that the only Additional Shares of Common Stock so issued
        were the Additional Shares of Common Stock, if any, actually issued or
        sold on the exercise of such rights or options or rights of conversion
        of such Convertible Securities, and such Additional Shares of Common
        Stock, if any, were issued or sold for the consideration actually
        received by the Corporation upon such exercise, plus the consideration,
        if any, actually received by the Corporation for the granting of all
        such rights or options, whether or not exercised, plus the consideration
        received for issuing or selling the Convertible Securities actually
        converted, plus the consideration, if any, actually received by the
        Corporation (other than by cancellation of liabilities or obligations
        evidenced by such Convertible Securities) on the conversion of such
        Convertible Securities, provided that such readjustment shall not apply
        to prior conversions of Series B Preferred Stock, Series C Preferred
        Stock, Series D Preferred Stock, Series F Preferred Stock, Series G
        Preferred Stock, Series H Preferred Stock or Series I Preferred Stock.

              (iv) "Additional Shares of Common Stock" shall mean all shares of
        Common Stock issued by the Corporation or deemed to be issued pursuant
        to this Section (4)(k), whether or not subsequently reacquired or
        retired by the Corporation other than (A) shares of Series G Preferred
        Stock, Series H Preferred Stock and Series I Preferred Stock issued
        pursuant to the Series G Purchase Agreement or the agreements referred
        to in Section 5.11 thereof; (B) shares of Common Stock issued upon
        conversion of the Series B Preferred Stock, Series C Preferred Stock,
        Series D Preferred Stock, Series F Preferred Stock, Series G Preferred
        Stock, Series H Preferred Stock or Series I Preferred Stock; (C) Common
        Stock and/or options, warrants or other Common Stock purchase rights,
        and the Common Stock issued pursuant to such options, warrants or other
        rights to employees, officers or directors of, or consultants or
        advisors to the Corporation or any subsidiary pursuant to stock purchase
        or stock option plans or other arrangements that are approved by the
        Board of Directors of the Corporation; (D) shares of Common Stock issued
        pursuant to the exercise of

                                       27
<Page>

        options, warrants or convertible securities outstanding as of the Series
        F Original Issue Date (as defined in Section (3)(c)(i)); (E) warrants to
        purchase Common Stock, and the Common Stock issued pursuant to such
        warrants, that are issued to holders of the Senior Notes (as defined in
        Section (2)(i)); and (F) the issuance of Common Stock pursuant to
        Sections (2)(i), (5)(a)(ii) or (5)(b)(ii). The "Effective Price" of
        Additional Shares of Common Stock shall mean the quotient determined by
        dividing the total number of Additional Shares of Common Stock issued or
        sold, or deemed to have been issued or sold by the Corporation under
        this Section (4)(k), into the aggregate consideration received, or
        deemed to have been received by the Corporation for such issue under
        this Section (4)(k), for such Additional Shares of Common Stock.

        (l) CERTIFICATE OF ADJUSTMENT. In each case of an adjustment or
    readjustment of the applicable Preferred Stock Price for the number of
    shares of Common Stock or other securities issuable upon conversion of the
    Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
    Preferred Stock or Series I Preferred Stock, if the Series B Preferred
    Stock, Series C Preferred Stock, Series D Preferred Stock, Series F
    Preferred Stock, Series G Preferred Stock, Series H Preferred Stock or
    Series I Preferred Stock is then convertible pursuant to this Section (4),
    the Corporation, at its expense, shall compute such adjustment or
    readjustment in accordance with the provisions hereof and prepare a
    certificate showing such adjustment or readjustment, and shall mail such
    certificate, by first class mail, postage prepaid, to each registered holder
    of Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
    Preferred Stock or Series I Preferred Stock at the holder's address as shown
    in the Corporation's books. The certificate shall set forth such adjustment
    or readjustment, showing in detail the facts upon which such adjustment or
    readjustment is based, including a statement of (i) the consideration
    received or deemed to be received by the Corporation for any Additional
    Shares of Common Stock issued or sold or deemed to have been issued or sold,
    (ii) the Preferred Stock Price at the time in effect, (iii) the number of
    Additional Shares of Common Stock and (iv) the type and amount, if any, of
    other property which at the time would be received upon conversion of the
    Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
    Stock, Series F Preferred Stock, Series G Preferred Stock, Series H
    Preferred Stock or Series I Preferred Stock.

        (m) NOTICES OF RECORD DATE. Upon (i) any taking by the Corporation of a
    record of the holders of any class of securities for the purpose of
    determining the holders thereof who are entitled to receive any dividend or
    other distribution, or (ii) any Acquisition (as defined in Section (2)(i))
    or other capital reorganization of the Corporation, any reclassification or
    recapitalization of the capital stock of the Corporation, any merger or
    consolidation of the Corporation with or into any other corporation, or any
    Asset Transfer (as defined in Section (2)(i)), or any voluntary or
    involuntary dissolution, liquidation or winding up of the Corporation, the
    Corporation shall mail to each holder of Preferred Stock at least twenty
    (20) calendar days prior to the record date specified therein a notice
    specifying (A) the date on which any such record is to be taken for the
    purpose of such dividend or distribution and a description of such dividend
    or distribution, (B) the date on

                                       28
<Page>

    which any such Acquisition, reorganization, reclassification, transfer,
    consolidation, merger, Asset Transfer, dissolution, liquidation or winding
    up is expected to become effective, and (C) the date, if any, that is to be
    fixed as to when the holders of record of Common Stock (or other securities)
    shall be entitled to exchange their shares of Common Stock (or other
    securities) for securities or other property deliverable upon such
    Acquisition, reorganization, reclassification, transfer, consolidation,
    merger, Asset Transfer, dissolution, liquidation or winding up.

        (n) FRACTIONAL SHARES. No fractional shares of Common Stock shall be
    issued upon conversion of Series B Preferred Stock, Series C Preferred
    Stock, Series D Preferred Stock, Series F Preferred Stock, Series G
    Preferred Stock, Series H Preferred Stock or Series I Preferred Stock. All
    shares of Common Stock (including fractions thereof) issuable upon
    conversion of more than one share of Series B Preferred Stock, Series C
    Preferred Stock, Series D Preferred Stock, Series F Preferred Stock, Series
    G Preferred Stock, Series H Preferred Stock or Series I Preferred Stock by a
    holder thereof shall be aggregated for purposes of determining whether the
    conversion would result in the issuance of any fractional share. If, after
    the aforementioned aggregation, the conversion would result in the issuance
    of any fractional share, the Corporation shall, in lieu of issuing any
    fractional share, pay cash equal to the product of such fraction multiplied
    by the Common Stock's fair market value (as determined in accordance with
    Section (2)(k)) on the date of conversion.

        (o) RESERVATION OF STOCK. The Corporation shall at all times reserve and
    keep available out of its authorized but unissued shares of Common Stock
    such number of its shares of Common Stock as shall from time to time be
    sufficient to effect the conversion of all outstanding shares of Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    F Preferred Stock, Series G Preferred Stock, Series H Preferred Stock and
    Series I Preferred Stock and the exercise of all outstanding options and
    warrants of the Corporation. If at any time the number of authorized but
    unissued shares of Common Stock shall not be sufficient to effect the
    conversion of all then outstanding shares of the Series B Preferred Stock,
    Series C Preferred Stock, Series D Preferred Stock, Series F Preferred
    Stock, Series G Preferred Stock, Series H Preferred Stock and Series I
    Preferred Stock or the exercise of all outstanding options and warrants, the
    Corporation will take such corporate action as may, in the opinion of its
    counsel, be necessary to increase its authorized but unissued shares of
    Common Stock to such number of shares as shall be sufficient for such
    purposes.

        (p) NOTICES. Any notice required by the provisions of this Section (4)
    shall be in writing and shall be deemed effectively given: (i) upon personal
    delivery to the party to be notified, (ii) when sent by confirmed telex or
    facsimile if sent during normal business hours of the recipient; if not,
    then on the next business day, (iii) five (5) business days after having
    been sent by registered or certified mail, return receipt requested, postage
    prepaid, or (iv) one (1) business day after deposit with a nationally
    recognized overnight courier, specifying next day delivery, with written
    verification of receipt. All notices shall be addressed to each holder of
    record at the address of such holder appearing on the books of the
    Corporation.

                                       29
<Page>

        (q) PAYMENT OF TAXES. The Corporation will pay all taxes (other than
    taxes based upon income) and other governmental charges that may be imposed
    with respect to the issue or delivery of shares of Common Stock upon
    conversion of shares of Series B Preferred Stock, Series C Preferred Stock,
    Series D Preferred Stock, Series F Preferred Stock, Series G Preferred
    Stock, Series H Preferred Stock or Series I Preferred Stock, excluding any
    tax or other charge imposed in connection with any transfer involved in the
    issue and delivery of shares of Common Stock in a name other than that in
    which the shares of Series B Preferred Stock, Series C Preferred Stock,
    Series D Preferred Stock, Series F Preferred Stock, Series G Preferred
    Stock, Series H Preferred Stock or Series I Preferred Stock so converted
    were registered.

        (5) Redemption.

        (a) Series F Preferred Stock.

                (i) GENERALLY. In the event of a breach by the Corporation of
        any of the terms of this Restated Certificate of Incorporation, the
        Bylaws of the Corporation or the Amended and Restated Purchasers Rights
        Agreement, dated as of March 26, 2001, by and among the Corporation and
        certain holders of its capital stock, as the same may be amended or
        restated from time to time (including in connection with the issuance of
        Series G Preferred Stock, Series H Preferred Stock and Series I
        Preferred Stock) (the "Purchasers Rights Agreement"), which has a
        material adverse effect on the holders of the Series F Preferred Stock
        that is not cured within fifteen (15) days of receipt of written notice
        by the Corporation from a holder of Series F Preferred Stock (a "Series
        F Redemption Event"), the holders of a majority of the voting power of
        the outstanding shares of Series F Preferred Stock may elect to demand
        in writing (a "Series F Redemption Demand") the redemption of all or any
        portion of the shares of Series F Preferred Stock, from any source of
        funds legally available therefor, at a redemption price per share (the
        "Series F Redemption Price") equal to the amount of the Series F
        Liquidation Preference. The redemption under this Section (5)(a) shall
        take place on a date (the "Series F Redemption Date") that is no later
        than thirty (30) days after the receipt by the Corporation of the Series
        F Redemption Demand.

                (ii) INDENTURE RESTRICTION. Notwithstanding the foregoing, the
        Corporation shall not be obligated to redeem the shares of Series F
        Preferred Stock for cash pursuant to Section (5)(a)(i), if such
        redemption or the existence of the redemption provision would violate
        the terms of the Indenture (as defined in Section (2)(i)) pursuant to
        which the Senior Notes were issued, until 91 days after the date on
        which the Senior Notes mature. If the Corporation is unable to redeem
        the Series F Preferred Stock for cash as set forth above, the holders of
        a majority of the voting power of the outstanding shares of Series F
        Preferred Stock may elect to receive shares of Common Stock with a fair
        market value (as determined in accordance with Section (2)(k)) equal to
        the Series F Redemption Price.

                                       30
<Page>

                (iii) PROCEDURE. At least fifteen (15) days prior to a Series F
        Redemption Date, written notice shall be mailed, first class postage
        prepaid, to each holder of record (at the close of business on the
        business day next preceding the day on which notice is given) of the
        Series F Preferred Stock to be redeemed, at the address last shown on
        the records of the Corporation for such holder, notifying such holder of
        the redemption to be effected, specifying the number of shares to be
        redeemed from such holder, the Series F Redemption Date, the Series F
        Redemption Price, whether or not the Corporation may redeem the shares
        for cash, or if not, the number of shares of Common Stock issuable in
        lieu of cash as set forth in Section (5)(a)(ii) above, the place at
        which payment or delivery may be obtained and calling upon such holder
        to surrender to the Corporation, in the manner and at the place
        designated, his certificate or certificates representing the shares to
        be redeemed (the "Series F Redemption Notice"). Except as provided in
        Section (5)(c), on or after the applicable Series F Redemption Date,
        each holder of Series F Preferred Stock to be redeemed shall surrender
        to the Corporation the certificate or certificates representing such
        shares, in the manner and at the place designated in the Series F
        Redemption Notice, and thereupon the Series F Redemption Price of such
        shares (in cash or shares of Common Stock, as applicable) shall be
        payable to the order of the person whose name appears on such
        certificate or certificates as the owner thereof and each surrendered
        certificate shall be canceled. In the event less than all the shares
        represented by any such certificate are redeemed, a new certificate
        shall be issued representing the unredeemed shares.

                (iv) DEPOSIT OF REDEMPTION PRICE OR SHARES OF COMMON STOCK.
        Subject to the provisions set forth above, on or prior to each Series F
        Redemption Date, the Corporation shall deposit the Series F Redemption
        Price of all shares of Series F Preferred Stock designated for
        redemption in the Series F Redemption Notice and not yet redeemed with a
        bank or trust corporation as a trust fund for the benefit of the
        respective holder or holders of the shares designated for redemption and
        not yet redeemed, with irrevocable instructions and authority to the
        bank or trust corporation to pay the Series F Redemption Price for such
        shares to their respective holder or holders on or after the applicable
        Series F Redemption Date upon receipt of notification from the
        Corporation that such holder has surrendered his share certificate to
        the Corporation pursuant to Section (5)(a)(iii). As of the applicable
        Series F Redemption Date, the deposit shall constitute full payment of
        the shares to the holder or holders, and from and after the applicable
        Series F Redemption Date the shares so called for redemption shall be
        redeemed and shall be deemed to be no longer outstanding, and the holder
        or holders thereof shall cease to be stockholders with respect to such
        shares and shall have no rights with respect thereto except the rights
        to receive from the bank or trust corporation payment of the Series F
        Redemption Price of the shares, without interest, upon surrender of
        their certificates therefor. The balance of any moneys deposited by the
        Corporation pursuant to this Section (5)(a)(iv) remaining unclaimed at
        the expiration of two years following the applicable Series F Redemption
        Date shall thereafter be returned to the Corporation upon its request
        expressed in a resolution of its Board of Directors. In the event that
        the Corporation must issue new shares

                                       31
<Page>

        of Common Stock instead of cash pursuant to the provisions set forth in
        Section (5)(a)(ii), shares of Common Stock shall be delivered to the
        bank or trust corporation in lieu of such cash.

        (b) Series G Preferred Stock.

                (i) GENERALLY. In the event of a breach by the Corporation of
        any of the terms of this Restated Certificate of Incorporation, the
        Bylaws of the Corporation, or the Purchasers Rights Agreement, which has
        a material adverse effect on the holders of the Series G Preferred Stock
        that is not cured within fifteen (15) days of receipt of written notice
        by the Corporation from a holder of Series G Preferred Stock (a "Series
        G Redemption Event"), the holders of a majority of the voting power of
        the outstanding shares of Series G Preferred Stock may elect to demand
        in writing ("Series G Redemption Demand") the redemption of all or any
        portion of the shares of Series G Preferred Stock, from any source of
        funds legally available therefor, at a redemption price per share (the
        "Series G Redemption Price") equal to the amount of the Series G
        Liquidation Preference. The redemption under this Section (5)(b) shall
        take place on a date (the "Series G Redemption Date") that is no later
        than thirty (30) days after the receipt by the Corporation of the Series
        G Redemption Demand.

                (ii) INDENTURE RESTRICTION. Notwithstanding the foregoing, the
        Corporation shall not be obligated to redeem the shares of Series G
        Preferred Stock for cash pursuant to Section (5)(b)(i), if such
        redemption or the existence of the redemption provision would violate
        the terms of the Indenture until 91 days after the date on which the
        Senior Notes mature. If the Corporation is unable to redeem the Series G
        Preferred Stock for cash as set forth above, the holders of a majority
        of the voting power of the outstanding shares of Series G Preferred
        Stock may elect to receive shares of Common Stock with a fair market
        value (as determined in accordance with Section (2)(k)) equal to the
        Series G Redemption Price.

                (iii) PROCEDURE. At least fifteen (15) days prior to a Series G
        Redemption Date, written notice shall be mailed, first class postage
        prepaid, to each holder of record (at the close of business on the
        business day next preceding the day on which notice is given) of the
        Series G Preferred Stock to be redeemed, at the address last shown on
        the records of the Corporation for such holder, notifying such holder of
        the redemption to be effected, specifying the number of shares to be
        redeemed from such holder, the Series G Redemption Date, the Series G
        Redemption Price, whether or not the Corporation may redeem the shares
        for cash, or if not, the number of shares of Common Stock issuable in
        lieu of cash as set forth in Section (5)(b)(ii) above, the place at
        which payment or delivery may be obtained and calling upon such holder
        to surrender to the Corporation, in the manner and at the place
        designated, his certificate or certificates representing the shares to
        be redeemed (the "Series G Redemption Notice"). Except as provided in
        Section (5)(c), on or after the applicable Series G Redemption Date,
        each holder of Series G Preferred Stock to be redeemed shall surrender
        to the

                                       32
<Page>

        Corporation the certificate or certificates representing such shares, in
        the manner and at the place designated in the Series G Redemption
        Notice, and thereupon the Series G Redemption Price of such shares (in
        cash or shares of Common Stock, as applicable) shall be payable to the
        order of the person whose name appears on such certificate or
        certificates as the owner thereof and each surrendered certificate shall
        be canceled. In the event less than all the shares represented by any
        such certificate are redeemed, a new certificate shall be issued
        representing the unredeemed shares.

                (iv) DEPOSIT OF REDEMPTION PRICE OR SHARES OF COMMON STOCK.
        Subject to the provisions set forth above, on or prior to each Series G
        Redemption Date, the Corporation shall deposit the Series G Redemption
        Price of all shares of Series G Preferred Stock designated for
        redemption in the Series G Redemption Notice and not yet redeemed with a
        bank or trust corporation as a trust fund for the benefit of the
        respective holder or holders of the shares designated for redemption and
        not yet redeemed, with irrevocable instructions and authority to the
        bank or trust corporation to pay the Series G Redemption Price for such
        shares to their respective holder or holders on or after the applicable
        Series G Redemption Date upon receipt of notification from the
        Corporation that such holder has surrendered his share certificate to
        the Corporation pursuant to Section (5)(b)(iii). As of the applicable
        Series G Redemption Date, the deposit shall constitute full payment of
        the shares to the holder or holders, and from and after the applicable
        Series G Redemption Date the shares so called for redemption shall be
        redeemed and shall be deemed to be no longer outstanding, and the holder
        or holders thereof shall cease to be stockholders with respect to such
        shares and shall have no rights with respect thereto except the rights
        to receive from the bank or trust corporation payment of the Series G
        Redemption Price of the shares, without interest, upon surrender of
        their certificates therefor. The balance of any moneys deposited by the
        Corporation pursuant to this Section (5)(b)(iv) remaining unclaimed at
        the expiration of two years following the applicable Series G Redemption
        Date shall thereafter be returned to the Corporation upon its request
        expressed in a resolution of its Board of Directors. In the event that
        the Corporation must issue new shares of Common Stock instead of cash
        pursuant to the provisions set forth in Section (5)(b)(ii), shares of
        Common Stock shall be delivered to the bank or trust corporation in lieu
        of such cash.

        (c) Rights of Redeemed Stock; Default.

                (i) From and after the applicable Series F Redemption Date or
        Series G Redemption Date, unless there shall have been a default in
        payment of the Series F Redemption Price or Series G Redemption Price,
        as applicable (in cash or shares of Common Stock, as applicable), all
        rights of the holders of shares of Preferred Stock designated for
        redemption in the Series F Redemption Notice as holders of Series F
        Preferred Stock or in the Series G Redemption Notice as holders of
        Series G Preferred Stock, as applicable (except the right to receive the
        applicable Series F Redemption Price or Series G Redemption Price,
        respectively, without interest upon surrender of their certificate or
        certificates) shall cease with

                                       33
<Page>

        respect to such shares, and such shares shall not thereafter be
        transferred on the books of the Corporation or be deemed to be
        outstanding for any purpose whatsoever.

                (ii) If the Corporation fails to redeem for any reason,
        including, but not limited to, the insufficiency of funds legally
        available for the redemption of shares, the total number of shares of
        Preferred Stock to be redeemed on the applicable Series F Redemption
        Date or Series G Redemption Date, those funds which are legally
        available will be used to redeem the maximum possible number of such
        shares ratably among the holders of such shares to be redeemed based
        upon their holdings of Series F Preferred Stock with respect to Section
        (5)(a) or their holdings of Series G Preferred Stock with respect to
        Section (5)(b). The shares of Preferred Stock not redeemed shall remain
        outstanding and be entitled to all the rights and preferences provided
        herein or may be otherwise converted into shares of Common Stock
        pursuant to the provisions set forth in Sections (5)(a)(ii) or
        (5)(b)(ii). At any time thereafter when additional funds of the
        Corporation are legally available for the redemption of such shares of
        Preferred Stock, such funds will immediately be used to redeem the
        balance of the shares which the Corporation has become obliged to redeem
        on any applicable Redemption Date, but which it has not redeemed.

        (6) INCREASING COMMON STOCK. Subject to the provisions of this Restated
    Certificate of Incorporation, the number of authorized shares of Common
    Stock may be increased or decreased (but not below the number of shares of
    Common Stock then outstanding, issuable upon the conversion of the Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    F Preferred Stock, Series G Preferred Stock, Series H Preferred Stock and
    Series I Preferred Stock and any other convertible securities of the
    Corporation, and issuable upon the exercise of all outstanding options and
    warrants), by the affirmative vote of the holders of a majority of the
    voting power of the outstanding shares of Common Stock and Preferred Stock,
    voting together as a single class.

        (7) NO REISSUANCE OF SERIES B, SERIES C, SERIES D, SERIES F, SERIES G,
    SERIES H OR SERIES I PREFERRED STOCK. No share or shares of Series B
    Preferred Stock, Series C Preferred Stock, Series D Preferred Stock, Series
    F Preferred Stock, Series G Preferred Stock, Series H Preferred Stock or
    Series I Preferred Stock acquired by the Corporation by reason of
    redemption, purchase, or otherwise shall be reissued, and all such shares
    shall be canceled, retired and eliminated from the shares which the
    Corporation shall be authorized to issue.

    FIFTH: The Board of Directors shall have that number of Directors set out in
the Bylaws of the Corporation as adopted or as set from time to time by a duly
adopted amendment thereto by the Directors or stockholders of the Corporation,
and, notwithstanding any other provision of this Restated Certificate of
Incorporation, the authorized number of Directors may be changed by a resolution
of the Board of Directors. All directors shall be of one class. The directors of
the Corporation shall be elected by the stockholders entitled to vote thereon at
each annual meeting of stockholders and shall hold office after the annual
meeting of stockholders and until his or her

                                       34
<Page>

successor shall be elected and qualified, subject, however, to prior death,
resignation, disqualification or removal from office. The term of office of each
director in office at the time this Restated Certificate of Incorporation
becomes effective shall expire at the first annual meeting of stockholders held
after the issuance of the Series G Preferred Stock or upon the effectiveness of
a written consent of stockholders in lieu of an annual meeting in accordance
with Section 211(b) of the Delaware General Corporation Law, as the case may be.
Any newly created directorship resulting from an increase in the number of
directors may be filled by a majority of the Board of Directors then in office,
provided that a quorum is present, and any other vacancy on the Board of
Directors may be filled by a majority of the directors then in office, even if
less than a quorum, or by a sole remaining director. In no case shall a decrease
in the number of directors shorten the term of any incumbent director.

    SIXTH: In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to adopt, repeal, alter,
amend and rescind the Bylaws of the Corporation. Notwithstanding the foregoing,
the Bylaws may be rescinded, altered, amended or repealed in any respect by the
affirmative vote of the holders of at least a majority of the outstanding voting
stock of the Corporation, voting together as a single class.

    SEVENTH: Notwithstanding the provisions of Article Fifth, whenever the
holders of any one or more classes or series of Preferred Stock issued by the
Corporation have the right, voting separately by class or series, to elect
directors at an annual or special meeting of stockholders, the election, term of
office, filling of vacancies and other features of such directorships shall be
governed by the terms of this Restated Certificate of Incorporation or the
resolution or resolutions adopted by the Board of Directors pursuant to Article
Fourth applicable thereto.

    EIGHTH: Elections of directors at an annual or special meeting of
stockholders need not be by written ballot unless the Bylaws of the Corporation
shall so provide.

    NINTH:

    (a) Subject only to the exclusions set forth in paragraph (c) of this
Article Ninth, the Corporation shall hold harmless and indemnify, to the fullest
extent permitted by applicable law as it presently exists or may hereafter be
amended, each director or officer of the Corporation (each, an "Indemnitee")
against any and all liability and loss suffered and expenses (including
attorneys' fees), judgments, fines, excise taxes assessed with respect to any
employee benefit plan, or penalties and amounts paid in settlement actually and
reasonably incurred by Indemnitee in connection with any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative (including an action by or in the right of the Corporation), to
which Indemnitee is, was or at any time becomes a party, or is threatened to be
made a party, by reason of the fact that Indemnitee is, was or at any time
becomes a director or officer of the Corporation, or, while a director or
officer of the Corporation, is, or was serving, or at any time serves at the
request of the Corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise.

    (b) The expenses (including attorneys' fees) actually and reasonably
incurred by Indemnitee in defending any proceeding and any judgments, fines or
amounts to be paid in settlement shall be advanced by the Corporation at the
request of the Indemnitee and upon

                                       35
<Page>

delivery to the Corporation of an undertaking by such Indemnitee to repay all
amounts so advanced if it shall ultimately be determined that Indemnitee was not
entitled to be indemnified or was not to be fully indemnified.

    (c) No indemnity pursuant to this Article Ninth shall be paid by the
Corporation (i) for which payment is actually made to Indemnitee under a valid
and collectible insurance policy, except in respect of any excess beyond the
amount of payment under such insurance; (ii) for which Indemnitee is indemnified
by the Corporation pursuant to applicable law or otherwise than pursuant to this
Article Ninth; (iii) for an accounting of profits made from the purchase or sale
by Indemnitee of securities of the Corporation within the meaning of Section
16(b) of the Securities Exchange Act of 1934 and amendments thereto or similar
provisions of any state statutory law or common law; (iv) on account of
Indemnitee's conduct which is finally adjudged by a court to have been knowingly
fraudulent, deliberately dishonest or willful misconduct; (v) if a final
decision by a court having jurisdiction in the matter shall determine that such
indemnity is not lawful; or (vi) for an action, suit or proceeding (or portion
thereof) initiated by the Indemnitee without the prior approval of the Board of
Directors of the Corporation (other than an action, suit or proceeding (or a
portion thereof) initiated by the Indemnitee to enforce its rights hereunder).

    (d) All obligations of the Corporation contained herein shall continue
during the period Indemnitee is a director or officer of the Corporation (or,
while a director or officer of the Corporation, is, or was serving at the
request of the Corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise) and shall
continue thereafter so long as Indemnitee shall be subject to any possible claim
or threatened, pending or completed action, suit or proceeding, whether civil,
criminal or investigative, by reason of the fact that Indemnitee was a director
or officer of the Corporation or serving in any other capacity referred to
herein.

    (e) Promptly after receipt by Indemnitee of notice of the commencement of
any action, suit or proceeding, Indemnitee will, if a claim in respect thereof
is to be made against the Corporation under this Article Ninth, notify the
Corporation of the commencement thereof; but the omission so to notify the
Corporation will not relieve it from any liability which it may have to
Indemnitee otherwise than under this Article Ninth. With respect to any such
action, suit or proceeding as to which Indemnitee notifies the Corporation of
the commencement thereof, the Corporation will be entitled to participate
therein at its own expense.

    (f) Except as otherwise provided below, to the extent that it may wish, the
Corporation jointly with any other indemnifying party similarly notified will be
entitled to assume the defense thereof with counsel reasonably satisfactory to
the Indemnitee. After notice from the Corporation to Indemnitee of its election
so to assume the defense thereof, the Corporation will not be liable to
Indemnitee under this Article Ninth for any legal or other expenses subsequently
incurred by Indemnitee in connection with the defense thereof other than
reasonable costs of investigation or as otherwise provided below. Indemnitee
shall have the right to employ its counsel in such action, suit or proceeding,
but the fees and expenses of such counsel, incurred after notice from the
Corporation of its assumption of the defense thereof, shall be at the expense of
Indemnitee unless (i) the employment of counsel by Indemnitee has been
authorized by the Corporation, (ii) Indemnitee shall have reasonably concluded
that there may be a conflict of interest between the Corporation and Indemnitee
in the conduct of the defense of such, subject to

                                       36
<Page>

the approval of the Corporation, which approval shall not be unreasonably
withheld, or (iii) the Corporation shall not in fact have employed counsel to
assume the defense of such action, in each of which cases the fees and expenses
of counsel shall be at the expense of the Corporation. The Corporation shall not
be entitled to assume the defense of any action, suit or proceeding brought by
or on behalf of the Corporation or as to which Indemnitee shall have made the
conclusion provided for in (ii) above.

    (g) The Corporation shall not be liable to indemnify Indemnitee under this
Article Ninth for any amounts paid in settlement of any action or claim effected
without its written consent. The Corporation shall not settle any action or
claim in any manner which would impose any penalty or limitation on Indemnitee
without Indemnitee's written consent. Neither the Corporation nor Indemnitee
will unreasonably withhold their consent to any proposed settlement.

    (h) In the event Indemnitee is required to bring any action to enforce
rights or to collect moneys due under this Article Ninth and is successful in
such action, the Corporation shall promptly reimburse Indemnitee for all of
Indemnitee's reasonable fees and expenses in bringing and pursuing such action.

    (i) The provisions of this Article Ninth shall inure to the benefit of and
be enforceable by the Indemnitee's personal or legal representatives, executors,
administrators, heirs, devises and legatees.

    (j) The Corporation shall have power to purchase and maintain insurance, at
its expense, on behalf of any person who is or was an officer, director,
employee or agent of the Corporation or a subsidiary thereof, or is or was
serving at the request of the Corporation as an officer, director, partner,
member, employee, trustee or agent of another corporation, partnership, joint
venture, trust or other enterprise, including any employee benefit plan, against
any expense, liability or loss asserted against such person and incurred by such
person in any such capacity, or arising out of such person's status as such,
whether or not the Corporation would have the power to indemnify such person
against such expense, liability or loss under the Bylaws, the provisions of this
Article Ninth or the Delaware General Corporation Law.

    (k) The indemnification provided by this Article Ninth shall not be deemed
exclusive of any other rights to which a person seeking indemnification may be
entitled under any statute, the Bylaws, other provisions of this Restated
Certificate of Incorporation, agreement, vote of stockholders or disinterested
directors or otherwise, both as to action in such person's official capacity and
as to action in any other capacity while holding such office, and shall continue
as to a person who has ceased to be an officer or director of the Corporation or
a subsidiary thereof or an officer, director, partner, member, employee, trustee
or agent of another corporation, partnership, joint venture, trust or other
enterprise, including any employee benefit plan, and shall inure to the benefit
of the heirs, executors and administrators of such person.

    (l) This Article Ninth may be hereafter amended or repealed; provided,
however, that no amendment or repeal shall reduce, terminate, or otherwise
adversely affect the right of a person entitled to obtain indemnification
hereunder with respect to acts or omissions of such person occurring prior to
the effective date of such amendment or repeal.

                                       37
<Page>

    TENTH: A director shall not be personally liable to the Corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director,
provided that this Article shall not eliminate or limit the liability of a
director (i) for any breach of his duty of loyalty to the Corporation or its
stockholders, (ii) for acts or omissions not in good faith or which involve
intentional misconduct or a knowing violation of the law, (iii) under Section
174 of the Delaware General Corporation Law, or (iv) for any transaction from
which the director derives an improper personal benefit.

    If the Delaware General Corporation Law is hereafter amended to authorize
corporate action further limiting or eliminating the personal liability of
directors, then the liability of the director to the Corporation shall be
limited or eliminated to the fullest extent permitted by the Delaware General
Corporation Law, as so amended from time to time. Any repeal or modification of
this Article by the stockholders of the Corporation shall be prospective only,
and shall not adversely affect any limitation on the personal liability of a
director of the Corporation existing at the time of such repeal or modification.

    ELEVENTH: Any action required by applicable law to be taken at any annual or
special meeting of stockholders of the Corporation, or any action which may be
taken at any annual or special meeting of the stockholders, may be taken without
a meeting, without prior notice and without a vote, if a consent or consents in
writing, setting forth the action so taken, shall be signed by the holders of
outstanding stock having not less than the minimum number of votes that would be
necessary to authorize or take such action at a meeting at which all shares
entitled to vote thereon were present and voted and shall be delivered to the
Corporation by delivery to its registered office in the State of Delaware, its
principal place of business or an officer or agent of the Corporation having
custody of the book in which proceedings or meetings of stockholders are
recorded.

    TWELFTH: Special meetings of the stockholders of the Corporation for any
purpose or purposes may be called at any time only by the Chairman of the Board
of Directors, the Chief Executive Officer of the Corporation, the President of
the Corporation, or a majority of the members of the Board of Directors, and
such special meetings may not be called by any other person or persons;
provided, however, that if and to the extent that any special meeting of
stockholders may be called by any other person or persons specified in any other
provisions of this Restated Certificate of Incorporation or any amendment hereto
or any certificate filed under Section 151(g) of the Delaware General
Corporation Law, then such special meeting may also be called by the person or
persons, in the manner, at the times and for the purposes so specified.

    THIRTEENTH: The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Restated Certificate of Incorporation, in
the manner now or hereafter prescribed by statute, and all rights conferred on
stockholders herein are granted subject to this reservation.

    FOURTEENTH: Each reference in this Restated Certificate of Incorporation to
any provision of the Delaware General Corporation Law refers to the specified
provision of the General Corporation Law of the State of Delaware, as the same
now exists or as it may hereafter be amended or superseded.

                                       38
<Page>

    IN WITNESS WHEREOF, this Restated Certificate of Incorporation has been
executed on behalf of the Corporation this 19th day of July, 2001.

                                   BIRCH TELECOM, INC.

                                   By: /s/ Gregory C. Lawhon
                                      ----------------------------------------
                                      Gregory C. Lawhon, Senior Vice President

                                       39

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00028-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00028-of-00352.parquet"}]]