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                                                                     Exhibit 4.1

                                     FORM OF

                           CERTIFICATE OF DESIGNATIONS

                                       of

                        $3.25 CONVERTIBLE PREFERRED STOCK

                                       of

                               DELTA HOLDCO CORP.

                         (Pursuant to Section 151 of the
                        Delaware General Corporation Law)

     Delta Holdco Corp., a corporation organized and existing under the General
Corporation Law of the State of Delaware (hereinafter called the "Corporation"),
hereby certifies that the following resolution was adopted by the Board of
Directors of the Corporation as required by Section 151 of the General
Corporation Law acting by written consent on January 30, 2002:

     RESOLVED, that pursuant to the authority granted to and vested in the Board
of Directors of this Corporation in accordance with the provisions of the
Certificate of Incorporation of the Corporation, a series of Convertible
Preferred Stock, par value $5.00 per share, of the Corporation, be and hereby is
created, and that the number of shares thereof and the voting powers,
designations, preferences, limitations, restrictions, relative rights and
distinguishing designation of the shares of such series are as follows:

     Section 1. Designation and Amount. The designation of such series of
Preferred Stock authorized by this resolution shall be the $3.25 Convertible
Preferred Stock (herein the "Convertible Preferred Stock"). The number of shares
of Convertible Preferred Stock shall be 2,300,000.

     Section 2. Rank. All shares of Convertible Preferred Stock shall rank
prior, both as to payment of dividends and as to distributions of assets upon
liquidation, dissolution or winding up of the Corporation, whether voluntary or
involuntary, to all of the Corporation's now or hereafter issued Common Stock.
The term "Common Stock" shall mean the Common Stock, $1.60 par value per share,
of the Corporation as the same exists at the date hereof or as such stock may be
constituted from time to time.

     Section 3. Dividends. The holders of Convertible Preferred Stock shall be
entitled to receive, when, as and if declared by the Board of Directors out of
funds at the time legally available therefor, dividends at the rate of $3.25 per
annum per share, and no more, which shall be fully cumulative, shall accrue
without interest from the date of first issuance and shall be payable in cash
quarterly in arrears on February 15, May 15, August 15 and November 15 of each
year (except that if any such date is a Saturday, Sunday or legal holiday, then
such dividend shall be payable on the next succeeding day that is not a
Saturday, Sunday or legal holiday) to holders of record as they appear on the
stock transfer books of the Corporation on such record


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dates, not more than 60 nor less than 10 days preceding the payment dates for
such dividends, as are fixed by the Board of Directors. For purposes hereof, the
term "legal holiday" shall mean any day on which banking institutions are
authorized to close in New York, New York or in Houston, Texas. Subject to the
next paragraph of this Section 3, dividends on account of arrears for any past
dividend period may be declared and paid at any time, without reference to any
regular dividend payment date. The amount of dividends payable per share of
Convertible Preferred Stock for each quarterly dividend period shall be computed
by dividing the annual amount by four. The amount of dividends payable for the
initial dividend period and any period shorter than a full quarterly dividend
period shall be computed on the basis of a 360-day year of twelve 30-day months.
Holders of Convertible Preferred Stock shall not be entitled to any dividend,
whether payable in cash, property or stock, in excess of the full cumulative
dividends on such shares of Cumulative Preferred Stock.

     On each dividend payment date all dividends which shall have accrued on
each share of Convertible Preferred Stock outstanding on such dividend payment
date shall accumulate and be deemed to become "due" whether or not there shall
be funds legally available for the payment thereof. Any dividend which shall not
be paid on the dividend payment date on which it shall become due shall be
deemed to be "past due" until such dividend shall be paid or until the share of
Convertible Preferred Stock with respect to which such dividend became due shall
no longer be outstanding, whichever is the earlier to occur. No interest, sum of
money in lieu of interest, or other property or securities shall be payable in
respect of any dividend payment or payments which are past due. Dividends paid
on shares of Convertible Preferred Stock in an amount less than the total amount
of such dividends at the time accumulated and payable on such shares shall be
allocated pro rata on a share-by-share basis among all such shares at the time
outstanding.

     No dividends or other distributions, other than dividends payable solely in
shares of Common Stock or other capital stock of the Corporation ranking junior
as to dividends and as to liquidation rights to the Convertible Preferred Stock
which is neither convertible into, nor exchangeable or exercisable for, any
securities of the Corporation other than Common Stock or other capital stock of
the Corporation ranking junior as to dividends and as to liquidation rights to
the Convertible Preferred Stock, shall be paid, or declared and set apart for
payment, and no purchase, redemption or other acquisition shall be made by the
Corporation of, any shares of Common Stock or other capital stock of the
Corporation ranking junior as to dividends or as to liquidation rights to the
Convertible Preferred Stock (the "Junior Dividend Stock") unless and until all
accrued and unpaid dividends on the Convertible Preferred Stock, including the
full dividend for the then current dividend period, shall have been paid or
declared and set apart for payment and the Corporation is not in default in
respect of the optional redemption of any shares of Convertible Preferred Stock.

     No full dividends shall be paid or declared and set apart for payment on
any class or series of the Corporation's capital stock ranking, as to dividends,
on a parity with the Convertible Preferred Stock (the "Parity Dividend Stock")
for any period unless full cumulative dividends have been, or contemporaneously
are, paid or declared and set apart for such payment on the Convertible
Preferred Stock for all dividend payment periods terminating on or prior to the
date of payment of such full cumulative dividends. No full dividends shall be
paid or declared and set apart for payment on the Convertible Preferred Stock
for any period unless full

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cumulative dividends have been, or contemporaneously are, paid or declared and
set apart for payment on the Parity Dividend Stock for all dividend periods
terminating on or prior to the date of payment of such full cumulative
dividends. When dividends are not paid in full upon the Convertible Preferred
Stock and the Parity Dividend Stock, all dividends paid or declared and set
aside for payment upon shares of Convertible Preferred Stock and the Parity
Dividend Stock shall be paid or declared and set aside for payment pro rata so
that the amount of dividends paid or declared and set aside for payment per
share on the Convertible Preferred Stock and the Parity Dividend Stock shall in
all cases bear to each other the same ratio that accrued and unpaid dividends
per share on the shares of Convertible Preferred Stock and the Parity Dividend
Stock bear to each other.

     The Corporation shall not permit any subsidiary of the Corporation to
purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under this Section 3, purchase or
otherwise acquire such shares at such time and in such manner.

     Any reference to "distribution" contained in this Section 3 shall not be
deemed to include any distribution made in connection with any liquidation,
dissolution or winding up of the Corporation, whether voluntary or involuntary.

     Section 4. Liquidation Preference. In the event of any liquidation,
dissolution or winding up of the Corporation, whether voluntary or involuntary,
the holders of Convertible Preferred Stock shall be entitled to receive out of
the assets of the Corporation, whether such assets are stated capital or surplus
of any nature, an amount equal to the dividends accrued and unpaid thereon to
the date of final distribution to such holders, whether or not declared, without
interest, and a sum equal to $50.00 per share, and no more, before any payment
shall be made or any assets distributed to the holders of Common Stock or any
other class or series of the Corporation's capital stock ranking junior as to
liquidation rights to the Convertible Preferred Stock (the "Junior Liquidation
Stock"). In the event the assets of the Corporation available for distribution
to stockholders upon any liquidation, dissolution or winding up of the
Corporation, whether voluntary or involuntary, shall be insufficient to pay in
full the amounts payable with respect to the Convertible Preferred Stock and any
other class or series of the Corporation's capital stock which may hereafter be
created having parity as to liquidation rights with the Convertible Preferred
Stock (the "Parity Liquidation Stock"), the holders of the Convertible Preferred
Stock and the holders of the Parity Liquidation Stock shall share ratably in any
distribution of assets of the Corporation in proportion to the full respective
preferential amounts to which they are entitled (but only to the extent of such
preferential amounts). After payment in full of the liquidation preferences of
the shares of Convertible Preferred Stock, the holders of such shares shall not
be entitled to any further participation in any distribution of assets by the
Corporation. Neither a consolidation, merger or other business combination of
the Corporation with or into another corporation or other entity nor a sale or
transfer of all or part of the Corporation's assets for cash, securities or
other property shall be considered a liquidation, dissolution or winding up of
the Corporation for purposes of this Section 4 (unless in connection therewith
the liquidation of the Corporation is specifically approved).

     The holder of any shares of Convertible Preferred Stock shall not be
entitled to receive any payment owed for such shares under this Section 4 until
such holder shall cause to be

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delivered to the Corporation (i) the certificate(s) representing such shares of
Convertible Preferred Stock and (ii) transfer instrument(s) satisfactory to the
Corporation and sufficient to transfer such shares of Convertible Preferred
Stock to the Corporation free of any adverse interest. As in the case of the
Redemption Price referred to below, no interest shall accrue on any payment upon
liquidation after the due date thereof.

     Section 5. Redemption at Option of the Corporation. The Corporation, at its
option, may at any time redeem for shares of Common Stock the Convertible
Preferred Stock, in whole or from time to time in part, on any date set by the
Board of Directors, at the following redemption prices if redeemed during the
twelve-month period beginning May 15 of the year specified below:

                 Year                       Price Per Share
                 ----                       ---------------
                 2001                           $50.650
                 2002                           $50.325

and thereafter at $50.00 per share, plus, in each case, an amount equal to all
dividends on the Convertible Preferred Stock accrued and unpaid thereon, whether
or not declared or due, to the date fixed for redemption, such sum being
hereinafter referred to as the "Redemption Price" (subject to the right of the
holder of record of shares of Convertible Preferred Stock on a record date for
the payment of a dividend on the Convertible Preferred Stock to receive the
dividend due on such shares of Convertible Preferred Stock on the corresponding
dividend payment date). At no time shall the Convertible Preferred Stock be
redeemable for cash.

     The Corporation shall issue in payment of the Redemption Price for each
share of Convertible Preferred Stock to be redeemed such number of shares of
Common Stock as equals (x) the then-current Redemption Price of the Convertible
Preferred Stock, divided by (y) the market price (the "Market Price") of the
Common Stock. The Market Price shall be equal to the lower of (i) the average of
the daily closing prices of the Common Stock for the 20 consecutive trading days
immediately preceding the first business day immediately preceding the date of
the applicable redemption notice, or (ii) the closing price of the Common Stock
on the trading day immediately preceding the first business day immediately
preceding the date of the applicable redemption notice. The "closing price" for
each day shall be the last reported sales price regular way or, in case no such
reported sales takes place on such day, the average of the closing bid and asked
prices regular way for such day, in each case on the New York Stock Exchange
Composite Tape or, if not listed on the New York Stock Exchange, on the
principal national securities exchange on which the shares of Common Stock are
listed or admitted to trading or, if not listed or admitted to trading on a
national securities exchange, the last sale price regular way for the Common
Stock as published by the National Association of Securities Dealers Automated
Quotation System ("NASDAQ"), or if such last sale price is not so published by
NASDAQ or if no such sale takes place on such day, the mean between the closing
bid and asked prices for the Common Stock as published by NASDAQ. If the shares
of Common Stock are not listed or admitted to trading on a national securities
exchange or quoted by NASDAQ, the determination of Market Price shall be
determined in good faith by the Board of Directors of the Corporation or, if
such determination cannot be made, by a nationally recognized independent
investment banking firm selected in good faith by the Board of Directors of the
Corporation. For the

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purposes of this Section 5, trading day shall mean a day on which the securities
exchange specified for purposes of this Section 5 shall be open for business or,
if the shares of Common Stock shall not be listed on such exchange for such
period, a day with respect to which quotations of the character referred to in
the next preceding sentence shall be reported. In lieu of any fractional share
of Common Stock which would otherwise be issued upon any redemption of
Convertible Preferred Stock, the Corporation shall pay a cash adjustment in
respect of such fractional interest in an amount in cash (computed to the
nearest cent) equal to the Market Price multiplied by the fractional interest
that otherwise would have been deliverable upon such redemption of such
Convertible Preferred Stock.

     In case of the redemption of less than all of the then outstanding
Convertible Preferred Stock, the shares of Convertible Preferred Stock to be
redeemed shall be redeemed pro rata or by lot or in such other manner as the
Board of Directors may determine. Notwithstanding the foregoing, the Corporation
shall not redeem less than all of the Convertible Preferred Stock at any time
outstanding until all dividends accrued and in arrears upon all Convertible
Preferred Stock then outstanding shall have been paid for all past dividend
periods.

     Not more than 60 nor less than 30 days prior to the redemption date, notice
by first class mail, postage prepaid, shall be given to each holder of record of
the Convertible Preferred Stock to be redeemed, at such holder's address as it
shall appear upon the stock transfer books of the Corporation. Each such notice
of redemption shall specify the date fixed for redemption, the Redemption Price,
the place or places of payment, that payment will be made upon presentation and
surrender of the certificate(s) evidencing the shares of Convertible Preferred
Stock to be redeemed, that on and after the redemption date, dividends will
cease to accrue on such shares, the then effective conversion price pursuant to
Section 6 and that the right of holders to convert shall terminate at the close
of business on the redemption date (unless the Corporation defaults in the
payment of the Redemption Price).

     Any notice that is mailed as herein provided shall be conclusively presumed
to have been duly given, whether or not the holder of the Convertible Preferred
Stock receives such notice; and failure to give such notice by mail, or any
defect in such notice, to the holders of any shares designated for redemption
shall not affect the validity of the proceedings for the redemption of any other
shares of Convertible Preferred Stock. On or after the date fixed for redemption
as stated in such notice, each holder of the shares called for redemption shall
surrender the certificate evidencing such shares to the Corporation at the place
designated in such notice and shall thereupon be entitled to receive payment of
the Redemption Price as herein provided. If less than all the shares represented
by any such surrendered certificate are redeemed, a new certificate shall be
issued representing the unredeemed shares. If, on the date fixed for redemption,
shares of Common Stock and funds necessary for the redemption shall be available
therefor and shall have been irrecoverably deposited or set aside, then,
notwithstanding that the certificates evidencing any shares so called for
redemption shall not have been surrendered the dividends with respect to the
shares so called shall cease to accrue after the date fixed for redemption, the
shares shall no longer be deemed outstanding, the holders thereof shall cease to
be holders of Convertible Preferred Stock, and all rights whatsoever with
respect to the shares so called for redemption (except the right of the holders
to receive payment of the Redemption Price as herein provided without interest
upon surrender of their certificates therefor) shall terminate. At the close of
business on the redemption date, each holder of

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Convertible Preferred Stock so redeemed (unless the Corporation defaults on its
obligations to delivery shares of Common Stock or cash) shall be, without any
further action, deemed a holder of the number of shares of Common Stock for
which such Convertible Preferred Stock is redeemable.

     The shares of Convertible Preferred Stock shall not be subject to the
operation of any purchase, retirement, mandatory redemption or sinking fund.

     The holder of any shares of Convertible Preferred Stock redeemed upon any
exercise of the Corporation's redemption right shall not be entitled to receive
payment of the Redemption Price for such shares until such holder shall cause to
be delivered to the place specified in the notice given with respect to such
redemption (i) the certificate(s) representing such shares of Convertible
Preferred Stock redeemed and (ii) transfer instrument(s) satisfactory to the
Corporation and sufficient to transfer such shares of Convertible Preferred
Stock to the Corporation free of any adverse interest. No interest shall accrue
on the Redemption Price of any share of Convertible Preferred Stock after its
redemption date.

     All shares of Common Stock which may be delivered upon redemption of the
Convertible Preferred Stock will upon delivery be duly and validly issued and
fully paid and non-assessable, free of all liens and charges and not subject to
any preemptive rights, and prior to giving any notice of redemption the
Corporation shall take any corporate action necessary therefor.

     In the event that any shares of Convertible Preferred Stock shall be
converted into Common Stock pursuant to Section 6, then (i) the Corporation
shall not have the right to redeem such shares and (ii) shares of Common Stock
and any funds which shall have been deposited for the payment of the Redemption
Price for such shares of Convertible Preferred Stock shall be returned to the
Corporation immediately after such conversion (subject to declared dividends
payable to holders of shares of Convertible Preferred Stock on the record date
for such dividends being so payable, to the extent set forth in Section 6
hereof, regardless of whether such shares are converted subsequent to such
record date and prior to the related dividend payment date).

     Section 6. Conversion Privilege. (a) Right of Conversion. Subject to and
upon compliance with the provisions of this Section 6, each share of Convertible
Preferred Stock shall, at the option of the holder thereof, be convertible at
any time (unless such share is called for redemption, then to and including but
not after the close of business on the date fixed for such redemption, unless
the Corporation shall default in payment due upon redemption thereof), into that
number of fully paid and non-assessable shares of Common Stock (calculated as to
each conversion to the nearest 1/100th of a share) obtained by dividing $50.00
by the Conversion Price (as defined in Section 6(d)) in effect at such time and
by surrender of such share so to be converted in the manner provided in Section
6(b).

     (b) Manner of Exercise of Conversion Privilege. In order to exercise the
conversion privilege, the holder of one or more shares of Convertible Preferred
Stock to be converted shall surrender such shares at any of the offices or
agencies to be maintained for such purpose by the Corporation accompanied by the
funds, if any, required by the last paragraph of this Section 6(b) and shall
give written notice of conversion in the form provided on such shares

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of Convertible Preferred Stock (or such other notice as is acceptable to the
Corporation) to the Corporation at such office or agency that the holder elects
to convert the shares of Convertible Preferred Stock specified in said notice.
Such notice shall also state the name or names, together with address or
addresses, in which the certificate or certificates for shares of Common Stock
which shall be issuable in such conversion shall be issued. Each share of
Convertible Preferred Stock surrendered for conversion shall, unless the shares
issuable on conversion are to be issued in the same name as the name in which
such share is registered, be accompanied by instruments of transfer, in form
satisfactory to the Corporation, duly executed by the holder or his duly
authorized attorney and an amount sufficient to pay any transfer or similar tax.
As promptly as practicable after the surrender of such shares of Convertible
Preferred Stock and the receipt of such notice, instruments of transfer and
funds, if any, as aforesaid, the Corporation shall issue and shall deliver at
such office or agency to such holder, or on his written order, a certificate or
certificates for the number of full shares of Common Stock issuable upon the
conversion of such share of Convertible Preferred Stock in accordance with the
provisions of this Section 6 and a check or cash in respect of any fractional
interest in a share of Common Stock arising upon such conversion, as provided in
Section 6(c).

     Each conversion shall be deemed to have been effected immediately prior to
the close of business on the date on which such shares of Convertible Preferred
Stock shall have been surrendered and such notice (and any applicable
instruments of transfer and any required taxes) received by the Corporation as
aforesaid, and the person or persons in whose name or names any certificate or
certificates for shares of Common Stock shall be issuable upon such conversion
shall be deemed to have become the holder or holders of record of the shares
represented thereby at such time on such date, and such conversion shall be at
the Conversion Price in effect at such time on such date, unless the stock
transfer books of the Corporation shall be closed on that date, in which event
such person or persons shall be deemed to have become such holder or holders of
record at the close of business on the next succeeding day on which such stock
transfer books are open, but such conversion shall be at the Conversion Price in
effect on the date upon which such shares of Convertible Preferred Stock shall
have been surrendered and such notice received by the Corporation.

     Any shares of Convertible Preferred Stock surrendered for conversion during
the period from the close of business on the record date for any dividend
payment to the opening of business on the related dividend payment date shall
(unless such shares of Convertible Preferred Stock shall have been called for
redemption on a date in such period) be accompanied by payment, in funds
acceptable to the Corporation, of an amount equal to the dividend otherwise
payable on such dividend payment date; provided, however, that no such payment
need be made if there shall exist at the time of conversion a default in the
payment of dividends on the shares of Convertible Preferred Stocks. An amount
equal to such payment shall be paid by the Corporation on such dividend payment
date to the holder of such shares of Convertible Preferred Stock at the close of
business on such record date; provided, however, that if the Corporation shall
default in the payment of dividends on such dividend payment date, such amount
shall be paid to the person who made such required payment. Except as provided
for above in this Section, no adjustment shall be made for dividends accrued on
any shares of Convertible Preferred Stock converted or for dividends on any
shares issued upon the conversion of such shares as provided in this Section.

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     (c) Cash Payments in Lieu of Fractional Shares. No fractional shares or
scrip representing fractions of shares of Common Stock shall be issued upon
conversion of Convertible Preferred Stock. If more than one share of Convertible
Preferred Stock shall be surrendered for conversion at one time by the same
holder, the number of full shares of Common Stock issuable upon conversion
thereof shall be computed on the basis of the aggregate of $50.00 for each such
share so surrendered. In lieu of any fractional interest in a share of Common
Stock which would otherwise be deliverable upon the conversion of any share of
Convertible Preferred Stock, the Corporation shall pay to the holder of such
shares an amount in cash (computed to the nearest cent) equal to the closing
price (as defined in Section 5 hereof) on the business day next preceding the
day of conversion multiplied by the fractional interest that otherwise would
have been deliverable upon conversion of such share.

     (d) Adjustment of Conversion Price. The Conversion Price shall mean and be
$100, subject to adjustment from time to time by the Corporation as follows:

          (i) In case the Corporation shall (A) pay a dividend or make a
     distribution on its Common Stock in shares of Common Stock, (B) subdivide
     its outstanding shares of Common Stock into a greater number of shares, (C)
     combine its outstanding shares of Common Stock into a smaller number of
     shares, or (D) issue by reclassification of its Common Stock any shares of
     capital stock of the Corporation, then in each such case the Conversion
     Price in effect immediately prior to such action shall be adjusted so that
     the holder of any share of Convertible Preferred Stock thereafter
     surrendered for conversion shall be entitled to receive the number of
     shares of Common Stock or other capital stock of the Corporation which he
     would have owned or been entitled to receive immediately following such
     action had such share been converted immediately prior to the occurrence of
     such event. An adjustment made pursuant to this subsection (i) shall become
     effective immediately after the record date, in the case of a dividend or
     distribution, or immediately after the effective date, in the case of a
     subdivision, combination or reclassification. If, as a result of an
     adjustment made pursuant to this subsection (i), the holder of any share of
     Convertible Preferred Stock thereafter surrendered for conversion shall
     become entitled to receive shares of two or more classes of capital stock
     or shares of Common Stock and other capital stock of the Corporation, the
     Board of Directors (whose determination shall be conclusive and shall be
     described in a statement filed by the Corporation with the stock transfer
     or conversion agent, as appropriate) shall determine the allocation of the
     adjusted Conversion Price between or among shares of such classes of
     capital stock or shares of Common Stock and other capital stock.

          (ii) In case the Corporation shall issue rights or warrants to all
     holders of its outstanding shares of Common Stock entitling them (for a
     period expiring within 45 days after the record date mentioned below) to
     subscribe for or purchase shares of Common Stock at a price per share less
     than the current market price per share (as determined pursuant to
     subsection (iv) of this Section 6(d)) of the Common Stock (other than
     pursuant to any stock option, restricted stock or other incentive or
     benefit plan or stock ownership or purchase plan for the benefit of
     employees, directors or officers or any dividend reinvestment plan of the
     Corporation in effect at the time hereof or any other similar plan adopted
     or implemented hereafter), then the Conversion Price in effect immediately
     prior thereto shall be adjusted so that it shall equal the price determined
     by

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     multiplying the Conversion Price in effect immediately prior to the date of
     issuance of such rights or warrants by a fraction of which the numerator
     shall be the number of shares of Common Stock outstanding on the date of
     issuance of such rights or warrants (immediately prior to such issuance)
     plus the number of shares which the aggregate offering price of the total
     number of shares so offered would purchase at such current market price,
     and of which the denominator shall be the numbers of shares of Common Stock
     outstanding on the date of issuance of such rights or warrants (immediately
     prior to such issuance) plus the number of additional shares of Common
     Stock offered for subscription or purchase. Such adjustment shall be made
     successively whenever any rights or warrants are issued, and shall become
     effective immediately after the record date for the determination of
     stockholders entitled to receive such rights or warrants; provided,
     however, in the event that all the shares of Common Stock offered for
     subscription or purchase are not delivered upon the exercise of such rights
     or warrants, upon the expiration of such rights or warrants the Conversion
     Price shall be readjusted to the Conversion Price which would have been in
     effect had the numerator and the denominator of the foregoing fraction and
     the resulting adjustment been made based upon the number of shares of
     Common Stock actually delivered upon the exercise of such rights or
     warrants rather than upon the number of shares of Common Stock offered for
     subscription or purchase. In determining whether any rights or warrants
     entitle the holders to subscribe for or purchase shares of Common Stock at
     less than such current market price, and in determining the aggregate
     offering price of such shares of Common Stock, there shall be taken into
     account any consideration received by the Corporation for such rights or
     warrants, the value of such consideration, if other than cash, to be
     determined by the Board of Directors (whose determination shall be
     conclusive and shall be described in a statement filed by the Corporation
     with the stock transfer or conversion agent, as appropriate).
     Notwithstanding the foregoing, any adjustments to the Conversion Price with
     respect to the preferred stock purchase rights (the "Rights") of the
     Corporation associated with the shares of Common Stock, which Rights are
     governed by a Rights Agreement dated as of February 13, 2002, as amended
     (the "Rights Agreement"), or similar rights or warrants adopted or issued
     subsequent to the date hereof shall be made when such Rights or similar
     rights or warrants are exercised. If after the Distribution Date (as
     defined in the Rights Agreement or a similar date defined in a similar
     agreement), holders converting shares of Convertible Preferred Stock are
     not entitled to receive the Rights or similar rights or warrants which
     would otherwise be attributable (but for the date of conversion) to the
     shares of Common Stock received upon such conversion, then adjustment to
     the Conversion Price shall be made under this subsection (ii) as if the
     Rights or similar rights or warrants were then issued to holders of Common
     Stock. If such an adjustment is made and the Rights or similar rights or
     warrants are later redeemed, invalidated or terminated, then a
     corresponding reversing adjustment shall be made to the Conversion Price,
     on an equitable basis, to take account of such event. However, the
     Corporation may elect to provide that such shares of Common Stock issuable
     upon conversion of the Convertible Preferred Stock, whether or not issued
     after the Distribution Date for such Rights or such similar date for such
     similar rights or warrants, will be accompanied by the Rights or such
     similar rights or warrants which would otherwise be attributable (but for
     the date of conversion) to such shares of Common Stock, in which event the
     preceding two sentences shall not apply.


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          (iii) In case the Corporation shall, by dividend or otherwise,
     distribute to all holders of its outstanding Common Stock or capital stock
     (other than Common Stock), evidences of its indebtedness or assets
     (including securities and cash, but excluding any regular periodic cash
     dividend of the Corporation and dividends or distributions payable in stock
     for which adjustment is made pursuant to subsection (i) of this Section
     6(d)) or rights or warrants to subscribe for or purchase securities of the
     Corporation (excluding those referred to in subsection (ii) of this Section
     6(d)), then in each such case the Conversion Price shall be adjusted so
     that the same shall equal the price determined by multiplying the
     Conversion Price in effect immediately prior to the record date of such
     distribution by a fraction of which the numerator shall be the current
     market price per share as determined pursuant to subsection (iv) of this
     Section 6(d) of the Common Stock less the fair market value on such record
     date (as determined by the Board of Directors, whose determination shall be
     conclusive and shall be described in a statement filed by the Corporation
     with the stock transfer or conversion agent, as appropriate) of the portion
     of the capital stock or assets or the evidences of indebtedness or assets
     so distributed to the holder of one share of Common Stock or of such
     subscription rights or warrants applicable to one share of Common Stock,
     and of which the denominator shall be such current market price per share
     of Common Stock. Such adjustment shall become effective immediately after
     the record date for the determination of stockholders entitled to receive
     such distribution.

          (iv) For the purpose of any computation under subsections (ii) and
     (iii) of this Section 6(d), the current market price per share of Common
     Stock on any date shall be deemed to be the average of the closing price
     (as defined in Section 5) for the shorter of (A) 30 consecutive trading
     days (as defined in Section 5) ending on the last full trading day prior to
     the Time of Determination or (B) the period commencing on the date next
     succeeding the first public announcement of the issuance of such rights or
     warrants or such distribution through such last full trading day prior to
     the Time of Determination. For purposes of the foregoing, the term "Time of
     Determination" shall mean the time and date of the earlier of (I) the
     record date for determining stockholders entitled to receive the rights,
     warrants or distributions referred to in Section 6(d)(ii) and (iii) or (II)
     the commencement of "ex-dividend" trading on the exchange or market
     referred to in the definition of "closing price."

          (v) In any case in which this Section 6(d) shall require that an
     adjustment be made immediately following a record date or an effective
     date, the Corporation may elect to defer (but only until the filing by the
     Corporation with the stock transfer or conversion agent, as the case may
     be, of the certificate required by subsection (vii) of this Section 6(d))
     issuing to the holder of any share of Convertible Preferred Stock converted
     after such record date or effective date the shares of Common Stock
     issuable upon such conversion over and above the shares of Common Stock
     issuable upon such conversion on the basis of the Conversion Price prior to
     adjustment, and paying to such holder any amount of cash in lieu of a
     fractional share.

          (vi) No adjustment in the Conversion Price shall be required to be
     made unless such adjustment would require an increase or decrease of at
     least 1% of such price; provided, however, that any adjustments which by
     reason of this subsection (vi) are not

                                      -10-

<PAGE>

     required to be made shall be carried forward and taken into account in any
     subsequent adjustment. All calculations under this Section 6(d) shall be
     made to the nearest cent or to the nearest 1/1000th of a share, as the case
     may be. Anything in this Section 6(d) to the contrary notwithstanding, the
     Corporation shall be entitled to make such reduction in the Conversion
     Price, in addition to those required by this Section 6(d), as it in its
     discretion shall determine to be advisable in order that any stock
     dividend, subdivision of shares, distribution of rights to purchase stock
     or securities, or distribution of securities convertible into or
     exchangeable for stock hereafter made by the Corporation to its
     stockholders shall not be taxable to the recipients. Except as set forth in
     subsections (i), (ii) and (iii) above, the Conversion Price shall not be
     adjusted for the issuance of Common Stock, or any securities convertible
     into or exchangeable for Common Stock or carrying the right to purchase any
     of the foregoing, in exchange for cash, property or services.

          (vii) Whenever the Conversion Price is adjusted as herein provided,
     (A) the Corporation shall promptly file with the stock transfer or
     conversion agent, as appropriate, a certificate setting forth the
     Conversion Price after such adjustment and a brief statement of the facts
     requiring such adjustment and the manner of computing the same, which
     certificate shall be conclusive evidence of the correctness of such
     adjustment, and (B) the Corporation shall also mail or cause to be mailed
     by first class mail, postage prepaid, as soon as practicable to each holder
     of record of shares of Convertible Preferred Stock a notice stating that
     the Conversion Price has been adjusted and setting forth the adjusted
     Conversion Price. The stock transfer or conversion agent, as the case may
     be, shall not be under any duty or responsibility with respect to the
     certificate required by this subsection (vii) except to exhibit the same to
     any holder of shares of Convertible Preferred Stock who requests to inspect
     it.

          (viii) In the event that at any time, as a result of an adjustment
     made pursuant to subsection (i) of this Section 6(d), the holder of any
     share of Convertible Preferred Stock thereafter surrendered for conversion
     shall become entitled to receive any shares of the Corporation other than
     shares of Common Stock, thereafter the Conversion Price of such other
     shares so receivable upon conversion of any share of Convertible Preferred
     Stock shall be subject to adjustment from time to time in a manner and on
     terms as nearly equivalent as practicable to the provisions with respect to
     Common Stock contained in this Section.

          (ix) The Corporation from time to time may decrease the Conversion
     Price by any amount for any period of time if the period is at least 20
     days and if the decrease is irrevocable during the period. Whenever the
     Conversion Price is so decreased, the Corporation shall mail to holders of
     record of shares of Convertible Preferred Stock a notice of the decrease at
     least 15 days before the date the decreased Conversion Price takes effect,
     and such notice shall state the decreased Conversion Price and the period
     it will be in effect.

                                      -11-

<PAGE>

          (e) Notice to Holders Prior to Certain Corporate Actions. In case:

          (i) the Corporation shall take any action which would require an
     adjustment in the Conversion Price pursuant to Section 6(d)(iii); or

          (ii) the Corporation shall authorize the granting to the holders of
     its Common Stock generally of rights or warrants to subscribe for or
     purchase any shares of stock of any class or of any other rights; or

          (iii) there shall be any reorganization or reclassification of the
     Common Stock (other than a subdivision or combination of the outstanding
     Common Stock and other than a change in the par value of the Common Stock),
     or any consolidation or merger to which the Corporation is a party or any
     statutory exchange of securities with another corporation and for which
     approval of any stockholders of the Corporation is required, or any sale or
     transfer of all or substantially all of the assets of the Corporation; or

          (iv) there shall be a voluntary or involuntary dissolution,
     liquidation or winding-up of the Corporation;

then in each such case the Corporation shall cause to be given to the holders of
shares of Convertible Preferred Stock and the stock transfer or conversion
agent, as appropriate, as promptly as possible, but in any event at least 20
days prior to the applicable date hereinafter specified, a notice stating (i)
the date on which a record is to be taken for the purpose of such action or
granting of rights or warrants, or, if a record is not to be taken, the date as
of which the holders of Common Stock of record to be entitled to such
distribution, rights or warrants are to be determined, or (ii) the date on which
such reorganization, reclassification, consolidation, merger, statutory
exchange, sale, transfer, dissolution, liquidation or winding-up is expected to
become effective or occur, and the date as of which it is expected that holders
of Common Stock of record shall be entitled to exchange their shares of Common
Stock for securities, cash or other property deliverable upon such
reorganization, reclassification, consolidation, merger, statutory exchange,
sale, transfer, dissolution, liquidation or winding-up. Failure to give such
notice or any defect therein shall not affect the legality or validity or the
proceedings described in subsection (i), (ii), (iii) or (iv) of this Section
6(e).

     (f) Reservation of Shares of Common Stock. The Corporation covenants that
it will at all times reserve and keep available, free from preemptive rights,
out of the aggregate of its authorized but unissued shares of Common Stock or
its issued shares of Common Stock held in its treasury, or both, for the purpose
of effecting conversions of shares of Convertible Preferred Stock, the full
number of shares of Common Stock deliverable upon the conversion of all
outstanding shares of Convertible Preferred Stock not theretofore converted and
on or before (and as a condition of) taking any action that would cause an
adjustment of the Conversion Price resulting in an increase in the number of
shares of Common Stock deliverable upon conversion above the number thereof
previously reserved and available therefor, the Corporation shall take all such
action so required. For purposes of this Section 6(f), the number of shares of
Common Stock which shall be deliverable upon the conversion of all outstanding
shares of Convertible Preferred Stock shall be computed as if at the time of
computation all outstanding shares of Convertible Preferred Stock were held by a
single holder.

                                      -12-

<PAGE>

     Before taking any action which would cause an adjustment reducing the
Conversion Price below the then par value (if any) of the shares of Common Stock
deliverable upon conversion of the shares of Convertible Preferred Stock, the
Corporation shall take any corporate action which may, in the opinion of its
counsel, be necessary in order that the Corporation may validly and legally
issue fully paid and non-assessable shares of Common Stock at such adjusted
Conversion Price.

     (g) Transfer Taxes, Etc. The Corporation shall pay any and all documentary
stamp, issue or transfer taxes, and any other similar taxes payable in respect
of the issue or delivery of shares of Common Stock upon conversions of shares of
Convertible Preferred Stock pursuant hereto; provided, however, that the
Corporation shall not be required to pay any tax which may be payable in respect
of any transfer involved in the issue or delivery of shares of Common Stock in a
name other than that of the holder of the shares of Convertible Preferred Stock
to be converted and no such issue or delivery shall be made unless and until the
person requesting such issue or delivery has paid to the Corporation the amount
of any such tax or has established, to the satisfaction of the Corporation, that
such tax has been paid.

     (h) Consolidation or Merger or Sale of Assets. Notwithstanding any other
provision herein to the contrary, in case of any consolidation or merger to
which the Corporation is a party (other than a merger or consolidation in which
the Corporation is the continuing corporation and in which the Common Stock
outstanding immediately prior to the merger or consolidation is not exchanged
for cash, or the securities or other property of another corporation), or in
case of any sale or transfer to another corporation of the property of the
Corporation as an entirety or substantially as an entirety, or in the case of
any statutory exchange of securities with another corporation (other than in
connection with a merger or acquisition), then lawful provision shall be made by
the corporation formed by such consolidation or the corporation whose
securities, cash or other property will immediately after the merger or
consolidation be owned, by virtue of the merger or consolidation, by the holders
of Common Stock immediately prior to the merger or consolidation, or the
corporation which shall have acquired such assets or securities of the
Corporation (collectively the "Formed, Surviving or Acquiring Corporation"), as
the case may be, providing that the holder of each share of Convertible
Preferred Stock then outstanding shall have the right thereafter to convert such
share into the kind and amount of securities, cash or other property receivable
upon such consolidation, merger, statutory exchange, sale or transfer by a
holder of the number of shares of Common Stock into which such share of
Convertible Preferred Stock might have been converted immediately prior to such
consolidation, merger, statutory exchange, sale or transfer assuming such holder
of Common Stock did not exercise his rights of election, if any, as to the kind
or amount of securities, cash or other property receivable upon such
consolidation, merger, statutory exchange, sale or transfer (provided that, if
the kind or amount of securities, cash or other property receivable upon such
consolidation, merger, statutory exchange, sale or transfer is not the same for
each share of Common Stock in respect of which such rights of election shall not
have been exercised ("non-electing share"), then for the purposes of this
Section 6(h) the kind and amount of securities, cash or other property
receivable upon such consolidation, merger, statutory exchange, sale or transfer
for each non-electing share shall be deemed to be the kind and amount so
receivable per share by a plurality of the non-electing shares). The Formed,
Surviving or Acquiring Corporation, as the case may be, shall make provision in
its certificate or articles of incorporation or other constituent documents to
the end that the provisions set forth in

                                      -13-

<PAGE>

this Section 6(h) shall thereafter correspondingly be made applicable, as nearly
as may reasonably be, in relation to any shares of stock or other securities or
property thereafter deliverable on the conversion of the Convertible Preferred
Stock.

     The above provisions of this Section 6(h) shall similarly apply to
successive consolidations, mergers, statutory exchanges, sales or transfers.

     (i) Covenant as to Common Stock. The Corporation covenants that all shares
of Common Stock which may be delivered upon conversions of shares of Convertible
Preferred Stock will upon delivery be duly and validly issued and fully paid and
non-assessable, free of all liens and charges and not subject to any preemptive
rights.

     The Corporation covenants that if any shares of Common Stock to be provided
for the purpose of conversion of shares of Convertible Preferred Stock hereunder
require registration with or approval of any governmental authority under any
Federal or State law before such shares may be validly issued upon conversion,
the Corporation will in good faith and as expeditiously as possible endeavor to
secure such registration or approval, as the case may be.

     The Corporation further covenants that if at any time the Common Stock
shall be listed on the New York Stock Exchange or any other national securities
exchange, the Corporation will, if permitted by the rules of such exchange, list
and keep listed so long as the Common Stock shall be so listed on such exchange,
all Common Stock issuable upon conversion of the shares of Convertible Preferred
Stock.

     Section 7. Voting Rights. (a) General. The holders of Convertible Preferred
Stock shall not have any voting rights except as set forth below or as otherwise
from time to time required by law. In connection with any right to vote, each
holder of Convertible Preferred Stock will have one vote for each share held.
Any shares of Convertible Preferred Stock held by the Corporation or any entity
controlled by the Corporation shall not have voting rights hereunder and shall
not be counted in determining the presence of a quorum.

     (b) General Voting Rights. The holders of Convertible Preferred Stock shall
be entitled to vote together with the holders of Common Stock, as a single
class, on all matters submitted to the stockholders of the Corporation.

     (c) Default Voting Rights. Whenever dividends on the Convertible Preferred
Stock shall be in arrears in an amount equal to at least six quarterly dividends
(whether or not consecutive), (i) the number of members of the Board of
Directors of the Corporation shall be increased by two, effective as of the time
of election of such directors as hereinafter provided, and (ii) the holders of
the Convertible Preferred Stock (voting separately as a class with all other
affected classes or series of the Parity Dividend Stock upon which like voting
rights have been conferred and are exercisable) will have the exclusive right to
vote for and elect such two additional directors of the Corporation at any
meeting of stockholders of the Corporation at which directors are to be elected
held during the period such dividends remain in arrears. The right of the
holders of the Convertible Preferred Stock to vote for such two additional
directors shall terminate when all accrued and unpaid dividends on the
Convertible Preferred Stock have been declared and paid or set apart for
payment. The term of office of all directors so elected

                                      -14-

<PAGE>

shall terminate immediately upon the termination of the right of the holders of
the Convertible Preferred Stock and such Parity Dividend Stock to vote for such
two additional directors.

     The foregoing right of the holders of the Convertible Preferred Stock with
respect to the election of two directors may be exercised at any annual meeting
of stockholders or at any special meeting of stockholders held for such purpose.
If the right to elect directors shall have accrued to the holders of the
Convertible Preferred Stock more than 90 days preceding the date established for
the next annual meeting of stockholders, the President of the Corporation shall,
within 20 days after the delivery to the Corporation at its principal office of
a written request for a special meeting signed by the holders of at least ten
percent (10%) of the Convertible Preferred Stock then outstanding, call a
special meeting of the holders of the Convertible Preferred Stock to be held
within 60 days after the delivery of such request for the purpose of electing
such additional directors.

     The holders of the Convertible Preferred Stock and any Parity Dividend
Stock referred to above voting as a class shall have the right to remove without
cause at any time and replace any directors such holders have elected pursuant
to this Section 7.

     (d) Class Voting Rights. So long as the Convertible Preferred Stock is
outstanding, the Corporation shall not, without the affirmative vote or consent
of the holders of at least 66 2/3 percent of all outstanding Convertible
Preferred Stock (unless the vote or consent of a greater percentage is required
by applicable law or the Restated Articles of Incorporation of the Corporation),
voting separately as a class, (i) amend, alter or repeal (by merger,
consolidation or otherwise) any provision of the Restated Articles of
Incorporation or the Bylaws of the Corporation, as amended, so as to affect
adversely the relative rights, preferences, qualifications, limitations or
restrictions of the Convertible Preferred Stock, (ii) authorize or issue, or
increase the authorized amount of, any additional class or series of stock, or
any security convertible into stock of such class or series, ranking prior to
the Convertible Preferred Stock in respect of the payment of dividends or upon
liquidation, dissolution or winding up of the Corporation or (iii) effect any
reclassification of the Convertible Preferred Stock. A class vote on the part of
the Convertible Preferred Stock shall, without limitation, specifically not be
deemed to be required (except as otherwise required by law or resolution of the
Corporation's Board of Directors) in connection with: (a) the authorization,
issuance or increase in the authorized amount of any shares of any other class
or series of stock that ranks junior to, or on a parity with, the Convertible
Preferred Stock in respect of the payment of dividends and upon liquidation,
dissolution or winding up of the Corporation; or (b) the authorization, issuance
or increase in the amount of any notes, bonds, mortgages, debentures or other
obligations of the Corporation not convertible into or exchangeable, directly or
indirectly, for stock ranking prior to the Convertible Preferred Stock in
respect of the payment of dividends or upon liquidation, dissolution or winding
up of the Corporation.

     Section 8. Outstanding Shares. For purposes of this Certificate of
Resolution, all shares of Convertible Preferred Stock shall be deemed
outstanding except (i) from the date fixed for redemption pursuant to Section 5,
all shares of Convertible Preferred Stock that have been so called for
redemption under Section 5 if shares of Common Stock and funds necessary for
payment of the redemption price have been irrevocably set apart; (ii) from the
date of surrender of certificates representing shares of Convertible Preferred
Stock, all shares of

                                      -15-

<PAGE>

Convertible Preferred Stock converted into Common Stock; and (iii) from the date
of registration of transfer, all shares of Convertible Preferred Stock held of
record by the Corporation or any subsidiary of the Corporation.

     Section 9. Status of Acquired Shares. Shares of Convertible Preferred Stock
redeemed by the Corporation, received upon conversion pursuant to Section 6, or
otherwise acquired by the Corporation will be restored to the status of
authorized and unissued shares of Preferred Stock, without designation as to
series, and may thereafter be issued, but not as shares of Convertible Preferred
Stock.

     Section 10. Preemptive Rights. The Convertible Preferred Stock is not
entitled to any preemptive or subscription rights in respect of any securities
of the Corporation.

     Section 11. Severability of Provisions. Whenever possible, each provision
hereof shall be interpreted in a manner as to be effective and valid under
applicable law, but if any provision hereof is held to be prohibited by or
invalid under applicable law, such provision shall be ineffective only to the
extent of such prohibition or invalidity, without invalidating or otherwise
adversely affecting the remaining provisions hereof. If a court of competent
jurisdiction should determine that a provision hereof would be valid or
enforceable if a period of time were extended or shortened or a particular
percentage were increased or decreased, then such court may make such change as
shall be necessary to render the provision in question effective and valid under
applicable law.

                                      -16-

<PAGE>

     IN WITNESS WHEREOF, the Corporation has caused this certificate to be
signed by its President and attested to by its Secretary this ___ day of
__________, 2002.

                                             DELTA HOLDCO CORP.



                                             By:_________________________
                                                 Name:  Wayne W. Murdy
                                                 Title: Chairman, President and
                                                        Chief Executive Officer

Attest:

-----------------------
Name:  Britt D. Banks
Title: Vice President, General Counsel
       and Secretary

                                      -17-