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                                                                  EXHIBIT 3.1.11

                          NEXTLINK COMMUNICATIONS, INC.

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

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

              NEXTLINK Communications, Inc. (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 the
Corporation's Certificate of Incorporation, as amended (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
Special Committee of the Board of Directors, as authorized by the Board of
Directors, has duly approved and adopted the following resolution on June 14,
2000 (the "Resolution"):

                     RESOLVED that, pursuant to the authority vested in the
       Board of Directors by its Certificate of Incorporation, the Special
       Committee, as authorized by 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 H Convertible Participating Preferred Stock"),
       consisting of 131,250 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 Restated Certificate of Incorporation and in this Resolution
       as follows:

              1.     Number and Designation. 131,250 shares of the Preferred
Stock of the Corporation shall constitute a series designated as "Series H
Convertible Participating Preferred Stock" (the "Series H 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 H Preferred Stock.

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              "Liquidation Preference" with respect to a share of Series H
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.

              "Merger Agreement" means the Amended and Restated Agreement and
Plan of Merger and Share Exchange Agreement, dated as of May 10, 2000, by and
among Concentric Network Corporation, the Corporation, Eagle River, Craig O.
McCaw and NM Acquisition Corp.

              "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.

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

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

              "Series D Designation" means the Certificate of Designation for
the Series D Preferred Stock, as amended.

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

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

              "Series G Preferred Stock" means the Series G 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.

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              3.     Rank. (a) The Series G Preferred Stock and Series H
Preferred Stock each will, with respect to dividend rights and rights on
liquidation, winding-up and dissolution, rank (i) senior to the Corporation's
Series B Cumulative Convertible Preferred Stock, par value $.01 per share, the
Corporation's Series F Convertible Redeemable Preferred Stock, par value $.01
per share, 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 G Preferred Stock and Series H 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 the Series C
Preferred Stock, the Series D Preferred Stock and 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, the terms of which
expressly provide that such class or series will rank on a parity with the
Series G Preferred Stock and Series H 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 Series A Senior
Exchangeable Redeemable Preferred Shares, par value $.01 per share (the "Senior
Exchangeable Redeemable Preferred Shares"), the Corporation's Series E
Redeemable Exchangeable Preferred Shares, par value $.01 per share, 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 G Preferred Stock and
Series H 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 G Preferred Stock and Series H Preferred Stock vis-a-vis the other
shall be as set forth herein and in the Series G 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 H 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 H Preferred
Stock are outstanding, if the Corporation pays a dividend in cash, securities or
other property on the Common Stock (other than as described in the last sentence
of Section 4(e) of the Series G Designation) then at the same time the
Corporation shall declare and pay a dividend on each share of Series H Preferred
Stock in an amount equal to the Series H Per Share Participation Amount. The
"Series H 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 G Preferred
Stock and Series H 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 H Preferred Stock then
outstanding.

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              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 G Preferred
Stock and Series H 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 G Designation) of the shares
of Series G Preferred Stock and Series H 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 G Preferred Stock and Series H 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, 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 G Preferred Stock and the Series H 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 G Preferred Stock
and Series H Preferred Stock taken together, shall first be distributed to the
Series G Preferred Stock until it has received an amount equal to the aggregate
Preference Amounts (as defined in the Series G Designation) of all Series G
Preferred Stock outstanding as of the date of liquidation and thereafter 37.5%
to the Series G Preferred Stock and 62.5% to the Series H 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 G Preferred
Stock and Series H 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 G
Preferred Stock until it has received an amount equal to the aggregate
Preference Amounts (as defined in the Series G Designation) of all Series G
Preferred Stock outstanding as of the date of liquidation and thereafter 37.5%
to the Series G Preferred Stock and 62.5% to the Series H Preferred Stock. Any
amounts distributed with respect to the Series H Preferred Stock pursuant to
this paragraph 5(a) shall be allocated pro rata among the shares of Series H
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 G Preferred Stock and the Series H 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 H Preferred Stock, Series G
Preferred Stock and any Parity Securities shall not be entitled to share
therein.

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              6.     Redemption. (a) The Series H 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 H
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 H Preferred Stock if shares of the
Series G Preferred Stock are also redeemed on a proportional basis based on the
percentage of each series of shares outstanding at such time.

              (b)    Pursuant to the Series G 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 G 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 G
Preferred Stock, if any, at a redemption price per share in cash equal to the
Liquidation Preference (as set forth in the Series G Designation), without
interest; provided that upon any such election the Corporation shall be required
to redeem a proportional amount of the Series H Preferred Stock.

              (c)    Shares of Series H 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 H Preferred Stock shall be
reissued or sold as Series H Preferred Stock.

              (d)    If the Corporation is unable or shall fail to discharge its
obligation to redeem outstanding shares of Series G Preferred Stock and Series H
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 G
Preferred Stock and Series H 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 G 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 H 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

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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 H
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
H 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 H 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 H 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 H 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 G Designation, the holders of shares of Series G 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 G 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 G
Preferred Stock of its conversion option, a proportional amount, based on the
percentage of each series of shares outstanding, of the Series H 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 G Preferred Stock and Series H
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 G Preferred Stock and the
Series H Preferred Stock as set forth herein and in the Series G Designation as
of the date of conversion divided by $31.625, subject to adjustment from time to
time pursuant to paragraph 8(g) hereof (the "Conversion

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Price"). The Series H Preferred Stock outstanding as at any date shall be
convertible into a number of shares of Class A Common Stock (the "Aggregate
Series H 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 G Designation) with respect to all outstanding shares of
Series G 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 H Preferred Stock
being converted shall convert into a number of shares of Class A Common Stock
equal to the Aggregate Series H Conversion Shares divided by the number of
shares of Series H 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.

                     (ii)   In the case of any partial conversion of Series G
Preferred Stock by the holders thereof, selection of the Series H 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 H Preferred Stock is listed, or if the Series H 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 H Preferred Stock (or
all of the shares held by the holders who would hold less than 5 shares of
Series H 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 H 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 H Preferred Stock pursuant to paragraph 8(a)
(including the number of shares to be so converted), the holder of the shares of
Series H 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 H 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 H 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 H Preferred Stock not being so converted.

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                     (iii)  Each conversion of shares of Series H 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 G 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 G 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 H 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 H 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 automatic conversion of shares of Series H
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 H Preferred Stock not converted.

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

                     (ii)   If a holder of Series G Preferred Stock delivers to
the Corporation a certificate therefor and a notice of election to convert, the
Series H 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 H 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 H Preferred Stock.

                     (ii)   Prior to the delivery of any securities which the
Corporation shall be obligated to deliver upon conversion of the Series H
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 H Preferred Stock
pursuant hereto; provided that the Corporation

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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 H 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 H
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 H 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 H Preferred
Stock are deemed to have been converted.

              (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 H Preferred Stock including dividends paid as contemplated by Section 4),
(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 H 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 H 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), other than shares of
Common Stock issued pursuant to the Merger Agreement, 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

                                      -10-


<PAGE>   11


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. Notwithstanding anything herein to the
contrary, no adjustment in the Conversion Price shall be made under this clause
8(g)(ii): (a) to the extent the holders of Series H Preferred Stock participate
in any such distribution in accordance with Section 4 hereof and (b) to the
extent the holders of Series H Preferred Stock participate in any such
distribution by way of an adjustment to the Conversion Price pursuant to Section
8(g)(i) hereof.

                     (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 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 exerciseable 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

                                      -11-


<PAGE>   12


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 H Preferred Stock participate in any such distribution in accordance with
Section 4 hereof.

                     (iv)   (X) In case the Corporation shall fix a record date
for the making of a distribution (other than distributions paid exclusively in
cash under subparagraph (iv)(Y) below) 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 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.

              (Y) 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.

              (Z) Notwithstanding anything herein to the contrary, no adjustment
in the Conversion Price shall be made under this clause 8(g)(iv): (a) to the
extent the holders of Series H Preferred Stock participate in any such
distribution in accordance with Section 4 hereof and (b) to the extent the
holders of Series H Preferred Stock participate in any such distribution by way
of an adjustment to the Conversion Price pursuant to Section 8(g)(i) hereof.

                                      -12-


<PAGE>   13


                     (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 $.25 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 H 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 H 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.

                     (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
G Designation, the cumulative number of shares of Class A Common Stock issued or
issuable upon conversion of the Series G Preferred Stock and Series H Preferred
Stock, after giving effect to (x) the adjustments described in such paragraphs
and corresponding provisions in the Series G Designation and (y) all prior
conversions of Series G Preferred Stock and Series H 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 G and Series H 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 H 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 G
Preferred Stock and Series H 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 G and Series H Preferred Stock. Notwithstanding anything
to the contrary set forth above, the holders of Series G Preferred Stock and
Series H Preferred Stock shall be

                                      -13-


<PAGE>   14


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 G Preferred Stock,
Series H 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 G Preferred Stock and Series H 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 G Preferred
Stock and Series H 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 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 H 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 H 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 Class A Common Stock as a single class on all matters presented to the
holders of the Class A Common Stock for vote, except as hereinafter provided in
this Section 9 or as otherwise provided by law. So long as the provisions of (I)
Section 9(b)(i) hereof entitle the holders of Series H Preferred Stock to
designate the Series H Designee (as defined below) or (II) Section 9(b)(i) of
the Series D Designation entitle the holders of Series D Preferred Stock to
designate the Series D Designee (as defined in the Series D Designation), the
holders of Series H Preferred Stock shall not be entitled to vote as to the
election of other directors of the Corporation.

              (b)    (i)    So long as the holders of the outstanding shares of
Series D Preferred Stock are entitled, under Section 9(b)(i) of the Series D
Designation, to designate the Series D Designee to the Board of Directors, the
holders of the outstanding shares of Series H Preferred Stock shall not be
entitled to designate any directors for election to the Board of Directors.
Subject to the provisions of this Section 9, from and after the date the holders
of the outstanding shares of Series D Preferred Stock are no longer entitled to
designate the Series D Designee, the holders of the outstanding shares of Series
H Preferred Stock shall be entitled to designate one director (the "Series H
Designee") for election to the Board of Directors and such holders shall have
the exclusive right to vote for the election of such designee to the Board of
Directors. The foregoing right to designate and elect the Series H Designee
shall cease

                                      -14-


<PAGE>   15


immediately upon less than 20% of the aggregate number of shares of Series C
Preferred Stock issued on the original date of issuance of the Series C
Preferred Stock, Series D Preferred Stock issued on the original date of
issuance of the Series D Preferred Stock, Series G Preferred Stock issued on the
original date of issuance of the Series G Preferred Stock and Series H Preferred
Stock issued on the Issue Date (such aggregate number of shares of Series C
Preferred Stock, Series D Preferred Stock, Series G Preferred Stock and Series H
Preferred Stock being referred to herein as the "Total Preferred Shares") being
outstanding, whereupon the total number of directors then constituting the whole
Board of Directors shall automatically be decreased by one, and the term of
office of the Series H Designee shall terminate. For so long as, and only for so
long as, (i) less than 20% of the Total Preferred Shares are outstanding, (ii)
no shares of Series D Preferred Stock issued on the original date of issuance of
the Series D Preferred Stock are outstanding, and (iii) any shares of Series H
Preferred Stock issued on the Issue Date are outstanding, the holders of the
outstanding shares of the Series H Preferred Stock shall be entitled to
designate one board observer (the "Series H Board Observer"). The foregoing
right to designate the Series H Board Observer shall cease, and the observation
rights of the Series H Board Observer shall automatically terminate, immediately
upon there being no outstanding shares of Series H Preferred Stock. The Series H
Designee may be removed with or without cause by the holders of the shares of
Series H Preferred Stock and such holders shall have the right to designate and
elect a successor to any such removed Series H Designee. The "Series H 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 hereunder 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 H Preferred Stock 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 H Preferred Stock called as
hereinafter provided. Whenever the Corporation shall have fulfilled its
Mandatory Redemption Obligation hereunder, then the right of the holders of the
outstanding shares of the Series H 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 hereunder), and the term of office of any person elected
as director by the holders of outstanding shares of Series H 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 H 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 H 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 H Preferred Stock then outstanding addressed to the
Secretary of the Corporation shall,

                                      -15-


<PAGE>   16


call a special meeting of the holders of Series H 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 H 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 H Preferred Stock so designated shall have, and the Corporation
shall provide, access to the lists of stockholders to be called pursuant to the
provisions hereof. Notwithstanding the foregoing, so long as the holders of the
Series D Preferred Stock are entitled, collectively, to elect a director
pursuant to Section 9(b)(ii) of the Series D Designation, the holders of the
Series H Preferred Stock shall not be entitled to elect any directors under this
Section 9(b)(ii).

              (c)    Without the written consent of holders of a majority of the
outstanding shares of Series H Preferred Stock or the affirmative vote of
holders of a majority of the outstanding shares of Series H Preferred Stock at a
meeting of the holders of Series H 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 H Preferred
Stock or to authorize the issuance of, or to issue any, additional shares of
Series H Preferred Stock; provided that any such amendment that changes any
dividend or other amount payable on or the liquidation preference of the Series
H Preferred Stock shall require the written consent of holders of two-thirds of
the outstanding shares of Series H Preferred Stock or the affirmative vote of
holders of two-thirds of the outstanding shares of Series H Preferred Stock at a
meeting of the holders of Series H Preferred Stock called for such purpose.

              (d)    Without the written consent of holders of a majority of the
outstanding shares of Series H Preferred Stock or the affirmative vote of
holders of a majority of the outstanding shares of Series H 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 H 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 H 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,

                                      -16-


<PAGE>   17


participating, optional or other special rights and the qualifications,
limitations or restrictions thereof, that the Series H 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 H Preferred Stock (or shares or
interests into, or for which, the Series H 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 H Preferred Stock.

              (f)    In exercising the voting rights set forth in this paragraph
9, each share of Series H Preferred Stock shall have one vote for each share of
Class A Common Stock into which such share is convertible, calculated in
accordance with Section 8(a) hereof. Except as otherwise required by applicable
law or as set forth herein, the shares of Series H 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 G
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 G Preferred Stock of such occurrence and shall be required
to make an offer (the "Offer to Purchase") to each holder of shares of Series G
Preferred Stock (subject to the rights of the holders pursuant to Section 8
hereof) to repurchase such holder's shares of Series G 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 G Preferred Stock tender their shares pursuant to the Offer to
Purchase, the Corporation shall be required to purchase a proportional amount of
the Series H 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 H 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 H Preferred Stock
required to be purchased pursuant to Section 10(a) hereof, dividends will cease
to accrue with respect to the Series H Preferred Stock purchased and all rights
of holders of such tendered shares will terminate, except for the right to
receive payment therefor.

                                      -17-


<PAGE>   18


              (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 H 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 H 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 H 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.

              (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 NEXTLINK Communications, Inc. has caused
this Certificate of Designation to be signed by Gary D. Begeman, its Senior Vice
President and Secretary this 5th day of July, 2000.

                                    NEXTLINK COMMUNICATIONS, INC.


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




                                      -19-