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                                                                   EXHIBIT 3.1.7

       CERTIFICATE OF DESIGNATION OF THE POWERS, PREFERENCES AND RELATIVE,
          PARTICIPATING, OPTIONAL AND OTHER SPECIAL RIGHTS OF SERIES D
          CONVERTIBLE PARTICIPATING PREFERRED STOCK AND QUALIFICATIONS,
                      LIMITATIONS AND RESTRICTIONS THEREOF

           ---------------------------------------------------------
                         Pursuant to Section 151 of the
                General Corporation Law of the State of Delaware
           ---------------------------------------------------------

              NM Acquisition Corp., the successor by merger to NEXTLINK
Communications, Inc. and to be known as NEXTLINK Communications, Inc.
immediately after the filing of this Certificate of Designation (the
"Corporation"), a corporation organized and existing under the General
Corporation Law of the State of Delaware, does hereby certify that, pursuant to
authority conferred upon the board of directors of the Corporation (the "Board
of Directors") by Section 3 of its Amended and Restated Certificate of
Incorporation, as amended from time to time (the "Certificate of
Incorporation"), and pursuant to the provisions of Section 151 of the General
Corporation Law of the State of Delaware, said Board of Directors is authorized
to issue Preferred Stock of the Corporation in one or more series and the Board
of Directors has duly approved and adopted the following resolution on June 13,
2000 (the "Resolution"):

              RESOLVED that, pursuant to the authority vested in the Board of
Directors by Section 3 of its Certificate of Incorporation, and Section 151 of
the DGCL, the Board of Directors hereby creates, authorizes and provides for the
issuance of a series of preferred stock of the Corporation, par value $.01 per
share (such preferred stock designated as the "Series D Convertible
Participating Preferred Stock"), consisting of 265,625 shares and having the
powers, designation, preferences, relative, participating, optional and other
special rights and the qualifications, limitations and restrictions thereof that
are set forth in the Certificate of Incorporation and in this Resolution as
follows:

              1.     Number and Designation. 265,625 shares of the Preferred
Stock of the Corporation shall constitute a series designated as "Series D
Convertible Participating Preferred Stock" (the "Series D Preferred Stock").

              2.     Definitions. Unless the context otherwise requires, when
used herein the following terms shall have the meaning indicated.

              "Board of Directors" means the Board of Directors of the
Corporation.

              "Business Day" means any day except Saturday, Sunday and any day
which shall be a legal holiday or a day on which banking institutions in New
York City, New York generally are authorized or required by law or other
governmental actions to close.

              "Capital Stock" means, with respect to any person, any and all
shares, interests, participations, rights in, or other equivalents (however
designated and whether voting and/or non-voting) of such person's capital stock,
whether outstanding on the Issue Date or issued after


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the Issue Date, and any and all rights (other than any evidence of
indebtedness), warrants or options exchangeable for or convertible into such
capital stock.

              "Change of Control" will be deemed to have occurred at such time
as any of the following occur: (i) any person or any persons acting together
that would constitute a "group" for purposes of Section 13(d) of the Exchange
Act, or any successor provision thereto (other than Eagle River, Craig O. McCaw,
Wendy P. McCaw and their respective affiliates or an underwriter engaged in a
firm commitment underwriting on behalf of the Corporation), shall beneficially
own (within the meaning of Rule 13d-3 under the Exchange Act, or any successor
provision thereto) more than 50% of the aggregate voting power of all classes of
Voting Stock of the Corporation, (ii) neither Mr. Craig O. McCaw nor any person
designated by him to the Corporation as acting on his behalf shall be a director
of the Corporation or (iii) from and after the date on which the Corporation has
redeemed indefeasibly or defeased in full its obligations in respect of its
12-1/2% Senior Notes due April 15, 2006 or defeased the covenants applicable
thereto in accordance with their terms, during any period of two consecutive
years, individuals who at the beginning of such period constituted the Board of
Directors (together with any new directors whose election by the Board of
Directors or whose nomination for election by the shareholders of the
Corporation was proposed by a vote of a majority of the directors of the
Corporation then still in office who were either directors at the beginning of
such period or whose election or nomination for election was previously so
approved) cease for any reason to constitute a majority of the Board of
Directors then in office.

              "Class A Common Stock" means the Corporation's Class A Common
Stock, par value $.02 per share, now or hereafter authorized to be issued, and
any and all securities of any kind whatsoever of the Corporation which may be
exchanged for or converted into Class A Common Stock, any and all securities of
any kind whatsoever of the Corporation which may be issued on or after the date
hereof in respect of, in exchange for, or upon conversion of shares of Class A
Common Stock pursuant to a merger, consolidation, stock split, stock dividend,
recapitalization of the Corporation or otherwise.

              "Common Stock" means the Corporation's Class A Common Stock, the
Corporation's Class B Common Stock, par value $.02 per share, and any other
common stock of the Corporation.

              "Current Market Price" means the average of the daily Market
Prices of the Common Stock for ten consecutive trading days immediately
preceding the date for which such value is to be computed.

              "Eagle River" means Eagle River Investments, L.L.C., a limited
liability company formed under the laws of the State of Washington.

              "Exchange Act" means the Securities Exchange Act of 1934, as
amended, or any successor statute, and the rules and regulations promulgated
thereunder.

              "Issue Date" means the original date of issuance of shares of
Series D Preferred Stock by NEXTLINK.

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              "Liquidation Preference" with respect to a share of Series D
Preferred Stock means, as at any date, $1,000.00 plus an amount equal to any
accrued and unpaid dividends with respect to such share through such date.

              "Market Price" means, with respect to the Common Stock, on any
given day, (i) the price of the last trade, as reported on the Nasdaq National
Market, not identified as having been reported late to such system, or (ii) if
the Common Stock is so traded, but not so quoted, the average of the last bid
and ask prices, as those prices are reported on the Nasdaq National Market, or
(iii) if the Common Stock is not listed or authorized for trading on the Nasdaq
National Market or any comparable system, the average of the closing bid and
asked prices as furnished by two members of the National Association of
Securities Dealers, Inc. selected from time to time by the Corporation for that
purpose. If the Common Stock is not listed and traded in a manner that the
quotations referred to above are available for the period required hereunder,
the Market Price per share of Common Stock shall be deemed to be the fair value
per share of such security as determined in good faith by the Board of Directors
of the Corporation.

              "Net Realizable FMV" means, with respect to a share of Common
Stock, if calculable, the amount of gross proceeds net of underwriters'
discounts, commissions or other selling expenses received by or to be received
by the holder in connection with the sale of such share of Common Stock on a
when issued basis or immediately after the conversion or, in all other cases, an
amount equal to 97% of the Current Market Price of the Common Stock.

              "NEXTLINK" means NEXTLINK Communications, Inc., a Delaware
corporation and a predecessor to the Corporation.

              "Series C Designation" means the Certificate of Designation for
the Series C Preferred Stock.

              "Series C Preferred Stock" means the Series C Cumulative
Convertible Participating Preferred Stock, par value $.01 per share, of the
Corporation.

              "Voting Stock" means, with respect to any person, the Capital
Stock of any class or kind ordinarily having the power to vote for the election
of directors or other members of the governing body of such person.

              3.     Rank. (a) The Series C Preferred Stock and Series D
Preferred Stock each will, with respect to dividend rights and rights on
liquidation, winding-up and dissolution, rank (i) senior to the Corporation's 6
1/2% Series B Cumulative Convertible Preferred Stock, par value $.01 per share,
the Corporation's 7% Series F Convertible Redeemable Preferred Stock Due 2010,
all classes of Common Stock and to each other class of Capital Stock of the
Corporation or series of Preferred Stock of the Corporation established
hereafter by the Board of Directors of the Corporation the terms of which do not
expressly provide that such class or series ranks senior to, or on a parity
with, the Series C Preferred Stock and Series D Preferred Stock as to dividend
rights and rights on liquidation, winding-up and dissolution of the Corporation
(collectively referred to, together with all classes of Common Stock of the
Corporation, as "Junior Securities"); (ii) on a parity with each class of
Capital Stock of the Corporation or series of Preferred Stock of the Corporation
established hereafter by the Board of Directors of the

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Corporation, the terms of which expressly provide that such class or series
will rank on a parity with the Series C Preferred Stock and Series D Preferred
Stock as to dividend rights and rights on liquidation, winding-up and
dissolution (collectively referred to as "Parity Securities"); and (iii) junior
to the Corporation's 14% Series A Senior Exchangeable Redeemable Preferred
Shares, par value $.01 per share (the "Senior Exchangeable Redeemable Preferred
Shares"), the Corporation's the Corporation's 13 1/2% Series E Senior Redeemable
Exchangeable Preferred Stock due 2010, and to each class of Capital Stock of the
Corporation or series of Preferred Stock of the Corporation established
hereafter by the Board of Directors of the Corporation in accordance with
Section 9(d) hereof, the terms of which expressly provide that such class or
series will rank senior to the Series C Preferred Stock and Series D Preferred
Stock as to dividend rights and rights on liquidation, winding-up and
dissolution of the Corporation (collectively referred to as "Senior
Securities"); provided that the relative powers, rights and preferences of the
Series C Preferred Stock and Series D Preferred Stock vis-a-vis the other shall
be as set forth herein and in the Series C Designation.

                     (b)    The respective definitions of Junior Securities,
Parity Securities and Senior Securities shall also include any warrants, rights,
options or other securities exercisable or exchangeable for or convertible into
any of the Junior Securities, Parity Securities and Senior Securities, as the
case may be.

                     (c)    The Series D Preferred Stock shall be subject to the
creation of Junior Securities and Parity Securities and, to the extent permitted
by Section 9(d), Senior Securities.

              4.     Dividends. So long as any shares of Series D Preferred
Stock are outstanding, if the Corporation pays a dividend in cash, securities or
other property on the Common Stock then at the same time the Corporation shall
declare and pay a dividend on each share of Series D Preferred Stock in an
amount equal to the Series D Per Share Participation Amount. The "Series D Per
Share Participation Amount" means, as at any date, 62.5% of the amount of
dividends that would be paid with respect to the Series C Preferred Stock and
Series D Preferred Stock taken together if converted into Common Stock on the
date established as the record date with respect to such dividend on the Common
Stock divided by the number of shares of Series D Preferred Stock then
outstanding.

              5.     Liquidation Preference. (a) In the event of any
liquidation, dissolution or winding-up of the Corporation, whether voluntary or
involuntary, after any payment or distribution of the assets of the Corporation
(whether capital or surplus) shall be made to or set apart for the holders of
Senior Securities, and before any payment or distribution of the assets of the
Corporation (whether capital or surplus) shall be made to or set apart for the
holders of Junior Securities, the holders of the shares of Series C Preferred
Stock and Series D Preferred Stock taken together shall be entitled to receive
an amount in cash equal to the greater of (x) the aggregate Liquidation
Preferences (as set forth herein and in the Series C Designation) of the shares
of Series C Preferred Stock and Series D Preferred Stock as of the date of
liquidation, or (y) the aggregate amount that would have been received with
respect to the shares of Series C Preferred Stock and Series D Preferred Stock
if such stock had been converted to Common Stock immediately prior to such
liquidation, dissolution or winding-up. If, upon any liquidation, dissolution or
winding-up of the Corporation, the assets of the Corporation, or proceeds
thereof,

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shall be insufficient to pay in full the aforesaid amounts under clause (x) of
the preceding sentence and liquidating payments on all Parity Securities, then
such assets, or proceeds thereof, shall (i) be distributed among the shares of
Series C Preferred Stock and the Series D Preferred Stock taken together and all
such other Parity Securities ratably in accordance with the respective amounts
that would be payable on such shares of Preferred Stock and any such other
Parity Securities if all amounts payable thereon were paid in full and (ii) the
amount distributable under clause (i) to the Series C Preferred Stock and Series
D Preferred Stock taken together, shall first be distributed to the Series C
Preferred Stock until it has received an amount equal to the aggregate
Preference Amounts (as defined in the Series C Designation) of all Series C
Preferred Stock outstanding as of the date of liquidation and thereafter 37.5%
to the Series C Preferred Stock and 62.5% to the Series D Preferred Stock. If,
upon any liquidation, dissolution or winding-up of the Corporation, the assets
of the Corporation, or proceeds thereof, distributable to the Series C Preferred
Stock and Series D Preferred Stock taken together shall be sufficient to pay in
full the aforesaid amounts under clause (x) of the first sentence of this
subsection 5(a) then such amount shall first be distributed to the Series C
Preferred Stock until it has received an amount equal to the aggregate
Preference Amounts (as defined in the Series C Designation) of all Series C
Preferred Stock outstanding as of the date of liquidation and thereafter 37.5%
to the Series C Preferred Stock and 62.5% to the Series D Preferred Stock. Any
amounts distributed with respect to the Series D Preferred Stock pursuant to
this paragraph 5(a) shall be allocated pro rata among the shares of Series D
Preferred Stock. For the purposes of this paragraph 5, neither the sale,
conveyance, exchange or transfer (for cash, shares of stock, securities or other
consideration) of all or substantially all of the property or assets of the
Corporation nor the consolidation or merger of the Corporation with or into one
or more other entities shall be deemed to be a liquidation, dissolution or
winding-up of the Corporation.

                     (b)    Subject to the rights of the holders of any Parity
Securities, after payment shall have been made in full to the holders of the
Series C Preferred Stock and the Series D Preferred Stock taken together, as
provided in this paragraph 5, any other series or class or classes of Junior
Securities shall, subject to the respective terms and provisions (if any)
applying thereto, be entitled to receive any and all assets remaining to be paid
or distributed, and the holders of the Series D Preferred Stock, Series C
Preferred Stock and any Parity Securities shall not be entitled to share
therein.

              6.     Redemption. (a) The Series D Preferred Stock shall not be
redeemable by the Corporation prior to the later of (i) the fifth anniversary of
the Issue Date and (ii) the date on which the Corporation has redeemed
indefeasibly or defeased in full its obligations in respect of its 12 1/2%
Senior Notes due April 15, 2006 or defeased the covenants applicable thereto in
accordance with their terms (the "Redemption Trigger Date"). On and after the
Redemption Trigger Date, to the extent the Corporation shall have funds legally
available for such payment, and subject to the rights of the holders pursuant to
Section 8 hereof, the Corporation may redeem at its option shares of Series D
Preferred Stock, at any time in whole or from time to time in part, at a
redemption price per share equal to the Liquidation Preference as of the date
fixed for redemption, without interest; provided that the Corporation shall only
be entitled to redeem shares of the Series D Preferred Stock if shares of the
Series C Preferred Stock are also redeemed on a proportional basis based on the
percentage of each series of shares outstanding at such time.

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                     (b)    Pursuant to the Series C Designation, to the extent
the Corporation shall have funds legally available therefor, during the 180-day
period commencing on the tenth anniversary of the Issue Date, the holders of the
Series C Preferred Stock shall have the right to cause the Corporation to redeem
at any time in whole or from time to time in part outstanding shares of Series C
Preferred Stock, if any, at a redemption price per share in cash equal to the
Liquidation Preference (as set forth in the Series C Designation), without
interest; provided that upon any such election the Corporation shall be required
to redeem a proportional amount of the Series D Preferred Stock.

                     (c)    Shares of Series D Preferred Stock which have been
issued and reacquired by the Corporation in any manner, including shares
purchased or redeemed, shall (upon compliance with any applicable provisions of
the laws of the State of Delaware) be retired and have the status of authorized
and unissued shares of the class of Preferred Stock undesignated as to series
and may be redesignated and reissued as part of any series of the Preferred
Stock; provided that no such issued and reacquired shares of Series D Preferred
Stock shall be reissued or sold as Series D Preferred Stock.

                     (d)    If the Corporation is unable or shall fail to
discharge its obligation to redeem outstanding shares of Series C Preferred
Stock and Series D Preferred Stock pursuant to paragraph 6(b) (the "Mandatory
Redemption Obligation"), the Mandatory Redemption Obligation shall be discharged
as soon as the Corporation is able to discharge such Mandatory Redemption
Obligation. If and so long as any Mandatory Redemption Obligation with respect
to the Series C Preferred Stock and Series D Preferred Stock shall not be fully
discharged, the Corporation shall not (i) directly or indirectly, redeem,
purchase, or otherwise acquire any Parity Security or discharge any mandatory or
optional redemption, sinking fund or other similar obligation in respect of any
Parity Securities or (ii) declare or make any Junior Securities Distribution (as
defined in the Series C Designation), or, directly or indirectly, discharge any
mandatory or optional redemption, sinking fund or other similar obligation in
respect of any Junior Securities.

              7.     Procedure for Redemption. (a) In the event that fewer than
all the outstanding shares of Series D Preferred Stock are to be redeemed, in
the case of Section 6(a), the number of shares to be redeemed shall be
determined by the Board of Directors and the shares to be redeemed shall be
selected pro rata (with any fractional shares being rounded to the nearest whole
shares). Notwithstanding anything in Section 6 to the contrary, the Corporation
shall only redeem shares of Series D Preferred Stock pursuant to Section 6(a) or
6(b) on a proportional basis based on the percentage of each series of shares
outstanding at such time.

                     (b)    In the event the Corporation shall redeem shares of
Series D Preferred Stock pursuant to Section 6(a), notice of such redemption
shall be given by first class mail, postage prepaid, mailed not less than 30
days nor more than 60 days prior to the redemption date, to each holder of
record of the shares to be redeemed at such holder's address as the same appears
on the stock register of the Corporation; provided that neither the failure to
give such notice nor any defect therein shall affect the validity of the giving
of notice for the redemption of any share of Series D Preferred Stock to be
redeemed except as to the holder to whom the Corporation has failed to give said
notice or except as to the holder whose notice was defective. Each such notice
shall state: (i) the redemption date; (ii) the number of shares of Series

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D Preferred Stock to be redeemed and, if fewer than all the shares held by such
holder are to be redeemed, the number of shares to be redeemed from such holder;
(iii) the redemption price; (iv) the place or places where certificates for such
shares are to be surrendered for payment of the redemption price; and (v) that
dividends on the shares to be redeemed will cease to accrue on such redemption
date.

                     (c)    Notice having been mailed as aforesaid, if
applicable, from and after the redemption date, dividends on the shares of
Series D Preferred Stock so called for redemption shall cease to accrue, and all
rights of the holders thereof as stockholders of the Corporation (except the
right to receive from the Corporation the redemption price and except the right
to convert shares so called for redemption prior to the close of business on the
date immediately preceding the date fixed for such redemption) shall cease. Upon
surrender in accordance with said notice, if applicable, of the certificates for
any shares so redeemed (properly endorsed or assigned for transfer, if the Board
of Directors shall so require and the notice shall so state), such shares shall
be redeemed by the Corporation at the redemption price aforesaid. In case fewer
than all the shares represented by any such certificate are redeemed, a new
certificate shall be issued representing the unredeemed shares without cost to
the holder thereof.

              8.     Conversion. (a) (i) Pursuant to the provisions of the
Series C Designation, the holders of shares of Series C Preferred Stock have the
right, at any time in whole and from time to time in part, at such holders'
option, to convert any or all outstanding shares (and fractional shares) of
Series C Preferred Stock held by such holders into fully paid and non-assessable
shares of Class A Common Stock. Upon the exercise by any holder of Series C
Preferred Stock of its conversion option, a proportional amount, based on the
percentage of each series of shares outstanding, of the Series D Preferred Stock
shall automatically convert into fully paid and non-assessable shares of Class A
Common Stock, subject to the provisions of this Section 8. At any time and from
time to time the outstanding shares of Series C Preferred Stock and Series D
Preferred Stock taken together shall be convertible into a number of shares of
Class A Common Stock (the "Aggregate Conversion Shares") equal to the aggregate
Liquidation Preferences of the shares of the Series C Preferred Stock and the
Series D Preferred Stock as set forth herein and in the Series C Designation as
of the date of conversion divided by $63.25, subject to adjustment from time to
time pursuant to paragraph 8(g) hereof (the "Conversion Price"). The Series D
Preferred Stock outstanding as at any date shall be convertible into a number of
shares of Class A Common Stock (the "Aggregate Series D Conversion Shares")
equal to .625 times the excess, if any, of (A) the Aggregate Conversion Shares
over (B) the aggregate Preference Amounts (as defined in the Series C
Designation) with respect to all outstanding shares of Series C Preferred Stock
divided by the Net Realizable FMV of a share of Class A Common Stock at the time
of conversion. Each share of Series D Preferred Stock being converted shall
convert into a number of shares of Class A Common Stock equal to the Aggregate
Series D Conversion Shares divided by the number of shares of Series D Preferred
Stock then outstanding. Notwithstanding any call for redemption pursuant to
Section 6(a), the holders' right to convert shares so called for redemption
shall terminate at the close of business on the date immediately preceding the
date fixed for such redemption unless the Corporation shall default in making
payment of the amount payable upon such redemption.

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                            (ii) In the case of any partial conversion of Series
       C Preferred Stock by the holders thereof, selection of the Series D
       Preferred Stock for automatic conversion will be made by the Corporation
       in compliance with the requirements of the principal national securities
       exchange, if any, on which the Series D Preferred Stock is listed, or if
       the Series D Preferred Stock is not listed on a national securities
       exchange, on a pro rata basis, by lot or such other method as the
       Corporation, in its sole discretion, shall deem fair and appropriate;
       provided, however, that the Corporation may redeem all the shares held by
       holders of fewer than 5 shares of Series D Preferred Stock (or all of the
       shares held by the holders who would hold less than 5 shares of Series D
       Preferred Stock as a result of such redemption) as may be determined by
       the Corporation. The Corporation shall provide prompt written notice
       (including the number of shares so converted) of the automatic conversion
       of shares of Series D Preferred Stock pursuant to this paragraph 8 to the
       holders of record of the shares so converted.

                     (b)    (i) Promptly upon receipt of notice of automatic
conversion of shares of Series D Preferred Stock pursuant to paragraph 8(a)
(including the number of shares to be so converted), the holder of the shares of
Series D Preferred Stock so converted shall surrender the certificate
representing such shares at the principal executive offices of the Corporation.
Unless the shares issuable on conversion are to be issued in the same name as
the name in which such shares of Series D Preferred Stock are registered, each
certificate so surrendered shall be accompanied by instruments of transfer, in
form satisfactory to the Corporation, duly executed by the holder or the
holder's duly authorized attorney, and an amount sufficient to pay any transfer
or similar tax.

                            (ii) As promptly as practicable after the surrender
       by the holder of the certificates for shares of Series D Preferred Stock
       as aforesaid, the Corporation shall issue and shall deliver to such
       holder, or on the holder's written order to the holder's transferee, (x)
       a certificate or certificates for the whole number of shares of Class A
       Common Stock issuable upon the conversion of such shares in accordance
       with the provisions of this paragraph 8, (y) any cash adjustment required
       pursuant to Section 8(f), and (z) in the event of a conversion in part, a
       certificate or certificates for the whole number of shares of Series D
       Preferred Stock not being so converted.

                            (iii) Each conversion of shares of Series D
       Preferred Stock pursuant to paragraph 8(a) shall be deemed to have been
       effected immediately prior to the close of business on the date on which
       the certificates for shares of Series C Preferred Stock shall have been
       surrendered and the notice of election to convert received by the
       Corporation in accordance with the procedures set forth in Section 8 of
       the Series C Designation, and the person in whose name or names any
       certificate or certificates for shares of Class A Common Stock shall be
       issuable upon such conversion shall be deemed to have become the holder
       of record of the shares of Class A Common Stock represented thereby at
       such time on such date and such conversion shall be into a number of
       whole shares of Class A Common Stock in respect of the shares of Series D
       Preferred Stock being converted as determined in accordance with this
       Section 8 at such time on such date. All shares of Class A Common Stock
       delivered upon conversion of the Series D 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.
       Upon

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       automatic conversion of shares of Series D Preferred Stock, the shares so
       converted shall no longer be deemed to be outstanding and all rights of a
       holder with respect to such converted shares shall immediately terminate
       except the right to receive the Class A Common Stock and other amounts
       payable pursuant to this paragraph 8 and a certificate or certificates
       representing the shares of Series D Preferred Stock not converted.

                     (c)    (i) Upon delivery to the Corporation by a holder of
shares of Series C Preferred Stock of a notice of election to convert, the right
of the Corporation to redeem the applicable shares of Series D Preferred Stock
shall terminate, regardless of whether a notice of redemption has been mailed as
aforesaid.

                            (ii) If a holder of Series C Preferred Stock
       delivers to the Corporation a certificate therefor and a notice of
       election to convert, the Series D Preferred Stock to be converted shall
       cease to accrue dividends pursuant to paragraph 4.

                            (iii) Except as provided above and in paragraph
       8(g), the Corporation shall make no payment or adjustment for accrued and
       unpaid dividends on shares of Series D Preferred Stock, whether or not in
       arrears, on conversion of such shares or for dividends theretofore paid
       on the shares of Class A Common Stock.

                     (d)    (i) The Corporation covenants that it will at all
times reserve and keep available, free from preemptive rights, such number of
its authorized but unissued shares of Class A Common Stock as shall be required
for the purpose of effecting conversions of the Series D Preferred Stock.

                            (ii) Prior to the delivery of any securities which
       the Corporation shall be obligated to deliver upon conversion of the
       Series D Preferred Stock, the Corporation shall comply with all
       applicable federal and state laws and regulations which require action to
       be taken by the Corporation.

                     (e)    The Corporation will pay any and all documentary
stamp or similar issue or transfer taxes payable in respect of the issue or
delivery of shares of Class A Common Stock on conversion of the Series D
Preferred Stock pursuant hereto; provided 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 Class A Common Stock in a name other than
that of the holder of the Series D 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.

                     (f)    In connection with the conversion of any shares of
Series D Preferred Stock, no fractions of shares of Class A Common Stock shall
be required to be issued to the holder of such shares of Series D Preferred
Stock, but in lieu thereof the Corporation shall pay a cash adjustment in
respect of such fractional interest in an amount equal to such fractional
interest multiplied by the Market Price per share of Class A Common Stock on the
business day next preceding the business day on which such shares of Series D
Preferred Stock are deemed to have been converted.

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                     (g)    (i) In case the Corporation shall at any time after
the Issue Date (A) declare a dividend or make a distribution on Common Stock
payable in Common Stock (other than dividends or distributions payable to
holders of the Series D Preferred Stock including dividends paid as contemplated
by Section 4(f)), (B) subdivide or split the outstanding Common Stock, (C)
combine or reclassify the outstanding Common Stock into a smaller number of
shares, (D) issue any shares of its Capital Stock in a reclassification of
Common Stock (including any such reclassification in connection with a
consolidation or merger in which the Corporation is the continuing corporation),
or (E) consolidate with, or merge with or into, any other person, the Conversion
Price in effect at the time of the record date for such dividend or distribution
or on the effective date of such subdivision, split, combination, consolidation,
merger or reclassification shall be adjusted so that the conversion of the
Series D Preferred Stock after such time shall entitle the holder to receive the
aggregate number of shares of Common Stock or other securities of the
Corporation (or other securities into which such shares of Common Stock have
been converted, exchanged, combined, consolidated, merged or reclassified
pursuant to clause 8(g)(i)(C), 8(g)(i)(D) or 8(g)(i)(E) above) which, if the
Series D Preferred Stock had been converted immediately prior to such time, such
holder would have owned upon such conversion and been entitled to receive by
virtue of such dividend, distribution, subdivision, split, combination,
consolidation, merger or reclassification. Such adjustment shall be made
successively whenever an event listed above shall occur.

                            (ii) In case the Corporation shall issue or sell any
       Common Stock (or rights, options, warrants or other securities
       convertible into or exercisable or exchangeable for shares of Common
       Stock) without consideration or for a consideration per share (or having
       a conversion, exchange or exercise price per share) less than the Current
       Market Price on the date of such issuance (or, in the case of convertible
       or exchangeable or exercisable securities, less than the Current Market
       Price as of the date of issuance of the rights, options, warrants or
       other securities in respect of which shares of Common Stock were issued)
       then, and in each such case, the Conversion Price shall be reduced to an
       amount determined by multiplying (A) the Conversion Price in effect on
       the day immediately prior to such date by (B) a fraction, the numerator
       of which shall be the sum of (1) the number of shares of Common Stock
       outstanding immediately prior to such sale or issuance multiplied by the
       then applicable Current Market Price (such Current Market Price, the
       "Adjustment Price") and (2) the aggregate consideration receivable by the
       Corporation for the total number of shares of Common Stock so issued (or
       into or for which the rights, options, warrants or other securities are
       convertible, exercisable or exchangeable), and the denominator of which
       shall be the sum of (x) the total number of shares of Common Stock
       outstanding immediately prior to such sale or issue and (y) the number of
       additional shares of Common Stock issued (or into or for which the
       rights, options, warrants or other securities may be converted, exercised
       or exchanged), multiplied by the Adjustment Price. In case any portion of
       the consideration to be received by the Corporation shall be in a form
       other than cash, the fair market value of such noncash consideration
       shall be utilized in the foregoing computation. Such fair market value
       shall be determined in good faith by the Board of Directors.

                            (iii) In case the Corporation shall fix a record
       date for the issuance on a pro rata basis of rights, options or warrants
       to the holders of its Common Stock or other securities entitling such
       holders to subscribe for or purchase shares of Common

                                      -10-


<PAGE>   11


       Stock (or securities convertible into or exercisable or exchangeable for
       shares of Common Stock) at a price per share of Common Stock (or having a
       conversion, exercise or exchange price per share of Common Stock, in the
       case of a security convertible into, or exercisable or exchangeable for,
       shares of Common Stock) less than the Current Market Price on such record
       date, the maximum number of shares of Common Stock issuable upon exercise
       of such rights, options or warrants (or conversion of such convertible
       securities) shall be deemed to have been issued and outstanding as of
       such record date and the Conversion Price shall be adjusted pursuant to
       paragraph 8(g)(ii) hereof, as though such maximum number of shares of
       Common Stock had been so issued for an aggregate consideration payable by
       the holders of such rights, options, warrants or other securities prior
       to their receipt of such shares of Common Stock. In case any portion of
       such consideration shall be in a form other than cash, the fair market
       value of such noncash consideration shall be determined as set forth in
       paragraph 8(g)(ii) hereof. Such adjustment shall be made successively
       whenever such record date is fixed; and in the event that such rights,
       options or warrants are not so issued or expire in whole or in part
       unexercised, or in the event of a change in the number of shares of
       Common Stock to which the holders of such rights, options or warrants are
       entitled (other than pursuant to adjustment provisions therein comparable
       to those contained in this paragraph 8(g)), the Conversion Price shall
       again be adjusted as follows: (A) in the event that all of such rights,
       options or warrants expire unexercised, the Conversion Price shall be the
       Conversion Price that would then be in effect if such record date had not
       been fixed; (B) in the event that less than all of such rights, options
       or warrants expire unexercised, the Conversion Price shall be adjusted
       pursuant to paragraph 8(g)(ii) to reflect the maximum number of shares of
       Common Stock issuable upon exercise of such rights, options or warrants
       that remain outstanding (without taking into effect shares of Common
       Stock issuable upon exercise of rights, options or warrants that have
       lapsed or expired); and (C) in the event of a change in the number of
       shares of Common Stock to which the holders of such rights, options or
       warrants are entitled, the Conversion Price shall be adjusted to reflect
       the Conversion Price which would then be in effect if such holder had
       initially been entitled to such changed number of shares of Common Stock.
       Notwithstanding anything herein to the contrary, no further adjustment to
       the Conversion Price shall be made upon the issuance or sale of Common
       Stock upon the exercise of any rights, options or warrants to subscribe
       for or purchase Common Stock, if any adjustment in the Conversion Price
       was made or required to be made upon the record date for the issuance or
       sale of such rights, options or warrants under this clause 8(g)(iii).
       Notwithstanding anything herein to the contrary, no adjustment in the
       Conversion Price shall be made under this clause 8(g)(iii) to the extent
       the holders of Series D Preferred Stock participate in any such
       distribution in accordance with Section 4 hereof.

                            (iv) In case the Corporation shall fix a record date
       for the making of a distribution to all holders of any class of Common
       Stock (including any such distribution made in connection with a
       consolidation or merger in which the Corporation is the continuing
       corporation) of evidences of indebtedness, assets or other property, the
       Conversion Price to be in effect after such record date shall be
       determined by multiplying the Conversion Price in effect immediately
       prior to such record date by a fraction, (A) the numerator of which shall
       be the Conversion Price immediately prior to such distribution less the
       fair market value (determined as set forth in paragraph 8(g)(ii) hereof)
       of the

                                      -11-


<PAGE>   12


       portion of the assets, other property or evidence of indebtedness so to
       be distributed which is applicable to one share of Common Stock, and (B)
       the denominator of which shall be the Conversion Price immediately prior
       to such distribution. Such adjustments shall be made successively
       whenever such a record date is fixed; and in the event that such
       distribution is not so made, the Conversion Price shall again be adjusted
       to be the Conversion Price which would then be in effect if such record
       date had not been fixed. An adjustment to the Conversion Price also shall
       be made in respect of dividends and distributions paid exclusively in
       cash to all holders of Common Stock (excluding any dividend or
       distribution in connection with the liquidation, dissolution or
       winding-up of the Corporation, whether voluntary or involuntary, and any
       cash that is distributed upon a merger, consolidation or other
       transaction for which an adjustment pursuant to paragraph 8(g)(i) is
       made) where the sum of (1) all such cash dividends and distributions made
       within the preceding 12 months in respect of which no adjustment has been
       made and (2) any cash and the fair market value (determined as set forth
       in paragraph 8(g)(ii) hereof)of other consideration paid in respect of
       any repurchases of Common Stock by the Corporation or any of its
       subsidiaries within the preceding 12 months in respect of which no
       adjustment has been made, exceeds 2% of the Corporation's market
       capitalization (being the product of the then Current Market Price of the
       Common Stock times the aggregate number of shares of Common Stock then
       outstanding on the record date for such distribution). The Conversion
       Price to be in effect after such adjustment shall be determined by
       subtracting from the Conversion Price in effect prior to such adjustment
       an amount equal to the quotient of (A) the sum of clause (1) and clause
       (2) above and (B) the number of shares of Common Stock outstanding on the
       date such adjustment is to be determined. Notwithstanding anything herein
       to the contrary, no adjustment in the Conversion Price shall be made
       under this clause 8(g)(iv) to the extent the holders of Series D
       Preferred Stock participate in any such distribution in accordance with
       Section 4 hereof.

                            (v) No adjustment to the Conversion Price pursuant
       to (a) paragraphs 8(g)(ii), 8(g)(iii) or 8(g)(iv) above shall be required
       unless such adjustment would require an increase or decrease of at least
       $.50 in the Conversion Price or (b) paragraph 8(g)(ii) above shall be
       required with respect to rights, options, warrants or other securities
       outstanding on the Issue Date or issued pursuant to the Company's
       employee benefit plans in effect on the Issue Date or reserved for
       issuance thereunder as of the Issue Date or stock options granted after
       the Issue Date pursuant to any stock option plans adopted by the Board of
       Directors so long as such options have an exercise price not less than
       the Market Price on the day preceding such grant; provided, however, that
       any adjustments which by reason of this paragraph 8(g)(v)(a) are not
       required to be made shall be carried forward and taken into account in
       any subsequent adjustment. All calculations under this paragraph 8(g)
       shall be made to the nearest four decimal points.

                            (vi) In the event that, at any time as a result of
       the provisions of this paragraph 8(g), a holder of Series D Preferred
       Stock upon subsequent conversion shall become entitled to receive any
       shares of Capital Stock of the Corporation other than Common Stock, the
       number of such other shares so receivable upon conversion of Series D
       Preferred Stock shall thereafter be subject to adjustment from time to
       time in a manner and on terms as nearly equivalent as practicable to the
       provisions contained herein.

                                      -12-


<PAGE>   13


                            (vii) If, as a result of the operation of paragraphs
       8(g)(ii), 8(g)(iii) or 8(g)(iv) above and corresponding provisions in the
       Series C Designation, the cumulative number of shares of Class A Common
       Stock issued or issuable upon conversion of the Series C Preferred Stock
       and Series D Preferred Stock, after giving effect to (x) the adjustments
       described in such paragraphs and corresponding provisions in the Series C
       Designation and (y) all prior conversions of Series C Preferred Stock and
       Series D Preferred Stock, would equal or exceed a number (the "Threshold
       Number") equal to 20% of the outstanding shares of Class A Common Stock
       as of the Issue Date and if the Company receives a written opinion of its
       outside counsel that the issuance of such shares in excess of the
       Threshold Number would violate the rules of the Nasdaq National Market or
       any other exchange on which the Class A Common Stock is then quoted or
       traded, then until and unless the Corporation obtains the approval of its
       common stockholders for the issuance of any such shares of Class A Common
       Stock in excess of the Threshold Number, the holders shall only be
       entitled to exercise their conversion rights with respect to a maximum
       number of Series C and Series D Preferred Stock that would not result in
       an amount of shares of Class A Common Stock being issued in excess of the
       Threshold Number, but in any case, the Conversion Price shall be adjusted
       as provided in such paragraphs. If, as a result of the operation of the
       preceding sentence, the conversion rights of the holders of Series D
       Preferred Stock are limited by operation thereof because appropriate
       stockholder approval has not been obtained, the Corporation agrees for
       the benefit of the holders of Series C Preferred Stock and Series D
       Preferred Stock to use its reasonable best efforts to seek, as promptly
       as reasonably practicable, the requisite approval of its common
       stockholders (and shall seek such approval as often as necessary to
       obtain such approval), and will recommend to its stockholders that they
       vote in favor of a resolution providing for such approval, for the amount
       of shares of Class A Common Stock that would be issued or issuable upon
       conversion in full of all outstanding Series C and Series D Preferred
       Stock. Notwithstanding anything to the contrary set forth above, the
       holders of Series C Preferred Stock and Series D Preferred Stock shall be
       entitled to exercise such holders' conversion rights in full (after
       giving effect to any and all anti-dilution adjustments resulting from
       operation of paragraphs 8(g)(ii), 8(g)(iii) or 8(g)(iv)) in connection
       with any merger, consolidation or other transaction in which such Series
       C Preferred Stock, Series D Preferred Stock or Class A Common Stock is
       being converted into or exchanged for cash, securities or other property
       in connection with such merger, consolidation or other transaction. In
       the event that the Corporation elects to redeem the shares of Series C
       Preferred Stock and Series D Preferred Stock at a time when the holders'
       right to convert such shares into Class A Common Stock is limited as
       provided in this paragraph (g), and such holders seek to exercise such
       conversion rights prior to the date fixed for redemption in accordance
       with this Section 8 (the "Redemption Date"), then if the total number of
       shares of Class A Common Stock issued or issuable upon conversion of such
       shares, after giving effect to any adjustments provided under the first
       sentence of this section (the "Cumulative Number"), would exceed the
       Threshold Number, the holders shall be entitled to convert such number of
       shares of Series C Preferred Stock and Series D Preferred Stock into a
       number of shares of Class A Common Stock up to the Threshold Number, and
       with respect to the balance of such shares, the Corporation shall cancel
       such shares and shall pay the holders in lieu thereof an amount in cash
       equal to (a)(i) the

                                      -13-


<PAGE>   14


       Cumulative Number minus (ii) the Threshold Number multiplied by (b) the
       Market Price per share of Class A Common Stock on the business day next
       preceding the business day which is deemed the Redemption Date.

                     (h)    All adjustments pursuant to this paragraph 8 shall
be notified to the holders of the Series D Preferred Stock and such notice shall
be accompanied by a schedule of computations of the adjustments.

              9.     Voting Rights. (a) The holders of record of shares of
Series D Preferred shall be entitled to vote on an as-converted basis
(calculated in accordance with Section 8(a) as of the close of trading on the
last trading day of the most recently ended fiscal quarter of the Corporation)
with the Common Stock as a single class on all matters presented to the holders
of the Common Stock for vote, except as hereinafter provided in this Section 9
or as otherwise provided by law. So long as the provisions of Section 9(b)(i)
entitle the holders of Series D Preferred Stock to designate the Series D
Designee (as defined below), the holders of Series D Preferred Stock shall not
be entitled to vote as to the election of other directors of the Corporation.

                     (b)    (i) On the Issue Date, the Board of Directors shall
cause the total number of directors then constituting the whole Board of
Directors to be increased by two and the holders of the outstanding shares of
Series C Preferred Stock shall be entitled to designate one director (the
"Series C Designee") for election to the Board of Directors of the Corporation
and, voting separately as a series, shall have the exclusive right to vote for
the election of such designee to the Board of Directors, and the holders of the
outstanding shares of Series D Preferred Stock shall be entitled to designate
one director (the "Series D Designee") for election to the Board of Directors of
the Corporation and, voting separately as a series, shall have the exclusive
right to vote for the election of such designee to the Board of Directors;
provided that, notwithstanding the foregoing, after the Issue Date, (i) the
holders of the outstanding shares of Series C Preferred Stock shall continue to
be entitled to designate the Series C Designee for election to the Board of
Directors and, voting separately as a series, shall continue to have the
exclusive right to vote for the election of the Series C Designee to the Board
of Directors, and the holders of the outstanding shares of the Series D
Preferred Stock shall continue to be entitled to designate the Series D Designee
for election to the Board of Directors and, voting separately as a series, shall
continue to have the exclusive right to vote for the election of the Series D
Designee to the Board of Directors, in each case, for as long as, and only for
as long as, at least 40% of the aggregate number of shares of Series C Preferred
Stock issued on the original date of issuance of the Series C Preferred Stock
and of shares of Series D Preferred Stock issued on the Issue Date (such
aggregate number of shares of Series C Preferred Stock and Series D Preferred
Stock being referred to herein as the "Total C and D Shares") remains
outstanding; (ii) the entitlement of the holders of outstanding shares of Series
D Preferred Stock to designate one director for election to the Board of
Directors, and the exclusive right of the holders of outstanding shares of
Series D Preferred Stock to vote, separately as a series, for the election of
such designee to the Board of Directors, shall cease immediately upon 20% or
less of the Total C and D Shares being outstanding, and the holders of the
outstanding shares of Series D Preferred Stock shall be entitled to designate
one board observer (the "Series D Board Observer"), for as long as, and only for
as long as, 20% or less (but at least one share of Series D Preferred Stock) of
the Total C and D Shares remains outstanding; (iii) immediately upon no shares
of Series D

                                      -14-


<PAGE>   15


Preferred Stock issued on the Series D Issue Date being outstanding, the
entitlement of the holders of outstanding shares of Series D Preferred Stock to
designate the Series D Board Observer, and the rights of such Board Observer,
shall cease; and (iv) immediately upon 20% or less of the Total C and D Shares
being outstanding, the Board of Directors shall cause the total number of
directors then constituting the whole Board of Directors to be decreased by one,
and the term of office of the Series D Designee shall terminate. The Series D
Designee may be removed with or without cause by the holders of the shares of
Series D Preferred Stock. The "Series D Board Observer" means a person who shall
not be a member of the Board of Directors and who shall have the rights as
agreed to with the Corporation, provided that such rights shall satisfy the
requirement of contractual management rights for purposes of the Department of
Labor's "plan assets" regulation.

                            (ii) If and whenever the Corporation shall have
       failed to discharge its Mandatory Redemption Obligation or the
       Corporation shall have failed to comply with Section 9(d) hereof, the
       total number of directors then constituting the whole Board of Directors
       automatically shall be increased by one and the holders of outstanding
       shares of Series D Preferred Stock, voting separately as a single series,
       shall be entitled to elect one additional director to serve on the Board
       of Directors at any annual meeting of stockholders or special meeting
       held in place thereof, or at a special meeting of the holders of the
       Series D Preferred Stock called as hereinafter provided. Whenever the
       Corporation shall have fulfilled its Mandatory Redemption Obligation,
       then the right of the holders of the outstanding shares of the Series D
       Preferred Stock to elect such additional director shall cease (but
       subject always to the same provisions for the vesting of such voting
       rights in the case of any future failure to fulfill any Mandatory
       Redemption Obligation), and the term of office of any person elected as
       director by the holders of outstanding shares of Series D Preferred Stock
       pursuant to this subparagraph (b)(ii) shall forthwith terminate and the
       total number of directors then constituting the whole Board of Directors
       automatically shall be reduced by one. At any time after voting power to
       elect one additional director shall have become vested and be continuing
       in the holders of outstanding shares of Series D Preferred Stock pursuant
       to this subparagraph (b)(ii), or if a vacancy shall exist in the office
       of a director elected by the holders of outstanding shares of Series D
       Preferred Stock pursuant to this subparagraph (b)(ii), a proper officer
       of the Corporation may, and upon the written request of the holders of
       record of at least twenty-five percent (25%) of the shares of Series D
       Preferred Stock then outstanding addressed to the Secretary of the
       Corporation shall, call a special meeting of the holders of Series D
       Preferred Stock, for the purpose of electing the one additional director
       which such holders are entitled to elect pursuant to this subparagraph
       (b)(ii). If such meeting shall not be called by a proper officer of the
       Corporation within twenty (20) days after personal service of said
       written request upon the Secretary of the Corporation, or within twenty
       (20) days after mailing the same within the United States by certified
       mail, addressed to the Secretary of the Corporation at its principal
       executive offices, then the holders of record of at least twenty-five
       percent (25%) of the outstanding shares of Series D Preferred Stock may
       designate in writing one of their number to call such meeting at the
       expense of the Corporation, and such meeting may be called by the person
       so designated upon the notice required for the annual meeting of
       stockholders of the Corporation and shall be held at the place for
       holding the annual meetings of stockholders. Any holder of Series D
       Preferred Stock so designated shall have, and the

                                      -15-


<PAGE>   16


       Corporation shall provide, access to the lists of stockholders to
       be called pursuant to the provisions hereof.

                     (c)    Without the written consent of holders of a majority
of the outstanding shares of Series D Preferred Stock or the affirmative vote of
holders of a majority of the outstanding shares of Series D Preferred Stock at a
meeting of the holders of Series D Preferred Stock called for such purpose, the
Corporation will not amend, alter or repeal any provision of the Restated
Certificate of Incorporation or this Certificate of Designation so as to
adversely affect the preferences, rights or powers of the Series D Preferred
Stock or to authorize the issuance of, or to issue any, additional shares of
Series D Preferred Stock; provided that any such amendment that changes any
dividend or other amount payable on or the liquidation preference of the Series
D Preferred Stock shall require the written consent of holders of two-thirds of
the outstanding shares of Series D Preferred Stock or the affirmative vote of
holders of two-thirds of the outstanding shares of Series D Preferred Stock at a
meeting of the holders of Series D Preferred Stock called for such purpose.

                     (d)    Without the written consent of holders of a majority
of the outstanding shares of Series D Preferred Stock or the affirmative vote of
holders of a majority of the outstanding shares of Series D Preferred Stock at a
meeting of such holders called for such purpose, the Corporation will not
create, authorize or issue any (i) Parity Securities or (ii) Senior Securities
except Senior Securities issued in accordance with paragraph (f)(ii) of the
Certificate of Designation for the Senior Exchangeable Redeemable Preferred
Shares as in effect on December 3, 1999.

                     (e)    Subject to the provisions of Sections 8 and 10
hereof, the Corporation may, without the consent of any holder of Series D
Preferred Stock, consolidate with or merge with or into, or convey, transfer or
lease all or substantially all its assets as an entirety to, any Person,
provided that: (1) the successor, transferee or lessee (if not the Corporation)
is organized and existing under the laws of the United States of America or any
State thereof or the District of Columbia and the Series D Preferred Stock shall
be converted into or exchanged for and shall become shares of, or interests in,
such successor, transferee or lessee, having in respect of such successor,
transferee, or lessee substantially the same powers, preferences and relative,
participating, optional or other special rights and the qualifications,
limitations or restrictions thereof, that the Series D Preferred Stock has
immediately prior to such transaction; and (2) the Corporation delivers to the
transfer agent an officers' certificate and an opinion of counsel stating that
such consolidation, merger, conveyance, transfer or lease complies with this
Certificate of Designation. In the event of any consolidation or merger or
conveyance, transfer or lease of all or substantially all of the assets of the
Corporation that is permitted pursuant to this paragraph (e), the successor
resulting from such consolidation or into which the Corporation is merged or the
transferee or lessee to which such conveyance, transfer or lease is made, will
succeed to, and be substituted for, and may exercise every right and power of,
the Corporation with respect to the Series D Preferred Stock (or shares or
interests into, or for which, the Series D Preferred Stock is converted or
exchanged), and thereafter, except in the case of a lease, the predecessor (if
still in existence) shall be released from its obligations and covenants with
respect to the Series D Preferred Stock.

                                      -16-



<PAGE>   17


                     (f)    In exercising the voting rights set forth in this
paragraph 9, each share of Series D Preferred Stock shall have one vote per
share. Except as otherwise required by applicable law or as set forth herein,
the shares of Series D Preferred Stock shall not have any relative,
participating, optional or other special voting rights and powers and the
consent of the holders thereof shall not be required for the taking of any
corporate action.

              10.    Change of Control. (a) Pursuant to the Series C
Designation, within thirty days of a Change of Control (the date of such
occurrence being the "Change of Control Date"), the Corporation shall notify the
holders of the Series C Preferred Stock of such occurrence and shall be required
to make an offer (the "Offer to Purchase") to each holder of shares of Series C
Preferred Stock (subject to the rights of the holders pursuant to Section 8
hereof) to repurchase such holder's shares of Series C Preferred Stock, or such
portion thereof as may be determined by such holder, at a price per share in
cash equal to 101% of the Liquidation Preference plus, without duplication, an
amount in cash equal to all accumulated and unpaid dividends per share
(including an amount in cash equal to a prorated dividend for the period from
the last Dividend Payment Date through such date); provided that if any holders
of Series C Preferred Stock tender their shares pursuant to the Offer to
Purchase, the Corporation shall be required to purchase a proportional amount of
the Series D Preferred Stock.

                     (b)    The Offer to Purchase must take place on a Business
Day (the "Change of Control Payment Date") not later than 30 days following the
Change of Control Date. On the Change of Control Payment Date, the Corporation
shall (A) accept for payment any Series D Preferred Stock required to be
purchased, (B) pay to the holders of shares so accepted the purchase price
therefor in cash and (C) cancel and retire each surrendered certificate. Unless
the Corporation defaults in the payment for the Series D Preferred Stock
required to be purchased pursuant to Section 10(a) hereof, dividends will cease
to accrue with respect to the Series D Preferred Stock purchased and all rights
of holders of such tendered shares will terminate, except for the right to
receive payment therefor.

                     (c)    The Corporation will comply with any securities laws
and regulations, to the extent such laws and regulations are applicable to the
repurchase of the Series D Preferred Stock in connection with an Offer to
Purchase.

                     (d)    Notwithstanding anything to the contrary contained
in this Section 10, the Company will not repurchase or redeem any such stock
pursuant to this Section 10 until it has repurchased or repaid all outstanding
debt obligations pursuant to rights triggered pursuant to the terms thereof
resulting from the Change of Control in question.

              11.    Reports. So long as any of the Series D Preferred Stock is
outstanding, in the event the Corporation is not required to file quarterly and
annual financial reports with the Securities and Exchange Commission pursuant to
Section 13 or Section 15(d) of the Exchange Act, the Corporation will furnish
the holders of the Series D Preferred Stock with reports containing the same
information as would be required in such reports.

              12.    General Provisions. (a) The term "person" as used herein
means any corporation, limited liability company, partnership, trust,
organization, association, other entity or individual.

                                      -17-


<PAGE>   18


                     (b)    The term "outstanding", when used with reference to
shares of stock, shall mean issued shares, excluding shares held by the
Corporation or a subsidiary of the Corporation.

                     (c)    The headings of the sections, paragraphs,
subparagraphs, clauses and subclauses of this Certificate of Designation are for
convenience of reference only and shall not define, limit or affect any of the
provisions hereof.




                                      -18-


<PAGE>   19


              IN WITNESS WHEREOF, said NM Acquisition Corp. has caused this
Certificate of Designation to be signed by Gary D. Begeman, its Vice President,
this 16th day of June, 2000.

                                                NM ACQUISITION CORP.




                                                By: /s/ Gary D. Begeman
                                                   ----------------------------
                                                Name: Gary D. Begeman
                                                Title: Vice President




                                      -19-