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                                                                   EXHIBIT 10.21

                           MPOWER HOLDING CORPORATION
                            2002 STOCK OPTION PLAN II

      1. PURPOSE AND EFFECT OF THE PLAN. This Stock Option Plan (the "Plan") is
intended to promote the interests of Mpower Holding Corporation, a Delaware
corporation (the "Company") and its owners by encouraging certain selected key
employees (including officers of the Company), consultants and Board of
Directors members who will be responsible for the future growth and continued
development of the Company to own, and to increase their ownership of, the
Company's Shares thereby giving them, as owners, an increased personal interest
in, and a greater concern for, the Company's success and progress. The Plan is
also intended to aid the Company in competing with other enterprises for the
services of new executives and key employees needed to help insure continued
development.

      2. NAME. The Plan shall be known as "Mpower Holding Corporation 2002 Stock
Option Plan II."

      3. DEFINITION OF TERMS. In addition to words and terms that may be defined
elsewhere in the Plan, the following words and terms as used in the Plan shall
have the following meanings unless the context or use fairly indicates another
or different meaning or intent, which definitions shall be equally applicable to
both the singular and plural forms of such words and terms.

           A. "Board" shall mean the Board of Directors of the Company.

           B. "Change of Control" shall mean:

      (a) The consummation of a merger or consolidation of the Company with or
into another entity or any other corporate reorganization, if more than 50% of
the combined voting power of the continuing or surviving entity's securities
outstanding immediately after such merger, consolidation or other reorganization
is owned by persons who were not stockholders of the Company immediately prior
to such merger, consolidation or other reorganization;

      (b) The sale, transfer or other disposition of all or substantially all of
the Company's assets;

      (c) A change in the composition of the Board, as a result of which
one-third or more of the incumbent directors are not directors who either (i)
had been directors of the Company on the date 24 months prior to the date of the
event that may constitute a Change in Control (the "original directors") or (ii)
were elected, or nominated for election, to the Board with the affirmative votes
of at least a majority of the aggregate of the original directors who were still
in office at the time of the election or nomination and the directors whose
election or nomination was previously so approved; or

      (d) Any transaction as a result of which any person is the "beneficial
owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
indirectly, of securities of the Company representing at least 50% of the total
voting power represented by the Company's then

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outstanding voting securities. For purposes of this Subsection (d), the term
"person" shall have the same meaning as when used in Sections 13(d) and 14(d) of
the Exchange Act but shall exclude (i) a trustee or other fiduciary holding
securities under an employee benefit plan of the Company or of a Parent or
Subsidiary and (ii) a corporation owned directly or indirectly by the
stockholders of the Company in substantially the same proportions as their
ownership of the common stock of the Company.

A transaction shall not constitute a Change in Control if its sole purpose is to
change the state of the Company's incorporation or to create a holding company
that will be owned in substantially the same proportions by the persons who held
the Company's securities immediately before such transaction.

           C. "Code" shall mean the Internal Revenue Code of 1986, as amended
from time to time.

           D. "Committee" shall have the meaning set forth in Item 5 hereof.

           E. "Common Stock" shall mean the common stock of the Company, $0.001
par value per share.

           F. "Employee" shall mean any employee of the Company, including
officers or directors of the Company who are employees of the Company.

           G. "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended.

           H. "Fair Market Value" shall mean the fair market value of a share of
Common Stock on a particular date determined as follows. In the event the
Company's Common Stock is listed on an established stock exchange, Fair Market
Value shall be deemed to be the closing price of the Company's Common Stock on
such stock exchange on such date or, if no sale of the Company's Common Stock
shall have been made on any stock exchange on that day, the Fair Market Value
shall be determined as such price for the next preceding day upon which a sale
shall have occurred. In the event the Company's Common Stock is not listed upon
an established exchange but is quoted on the National Association of Securities
Dealers Automated Quotation System ("NASDAQ"), the Fair Market Value shall be
deemed to be the closing sale price (if included in the national market list) or
the mean between the closing dealer "bid" and "asked" prices for the Company's
Common Stock as quoted on NASDAQ for such date, and if no closing sale price or
"bid" and "asked" prices are quoted for that day, the Fair Market Value shall be
determined by reference to such prices on the next preceding day on which such
prices are quoted. In the event the Company's said Common Stock is neither
listed on an established stock exchange nor quoted on NASDAQ, the Fair Market
Value on such date shall be determined by the Committee.

           I. "Non-Employee Director" shall have the meaning given that term by
Rule 16b-3 promulgated under the Exchange Act.

           J. "Non-Employees" shall mean any consultant of the Company or
director of the Company who is not an employee of the Company.


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           K. "NQSO" shall mean any Option granted under this Plan which is not
intended to qualify as an incentive stock option under Code Section 422.

           L. "Option" shall mean a stock option granted under the Plan.

           M. "Option Price" shall mean the purchase price of a Share of Common
Stock under an Option.

           N. "Participant" shall mean an Employee or Non-Employee to whom an
Option is granted under the Plan.

           O. "Parent" shall mean any corporation which at the time qualifies as
a parent of the Company under the definition of "parent corporation" contained
in Code Section 424(c).

           P. "SEC" shall mean the Securities and Exchange Commission.

           Q. "Shares" shall represent the shares of Common Stock in the Company
that may be acquired by exercise of Options hereunder.

           R. "Subsidiary" shall mean any corporation which at the time
qualifies as a subsidiary of the Company under the definition of "subsidiary
corporation" contained in Code Section 424(f).

      4. CHARACTERIZATION OF OPTIONS. All Options granted hereunder shall be
nonqualified options as provided in Code Section 83.

      5. ADMINISTRATION. The Plan shall be administered by a Stock Option
Committee (the "Committee") consisting of not less than two members all of whom
shall be Non-Employee Directors.

           A. The Committee shall be appointed by the Board from its membership.
The members of the Committee shall serve at the pleasure of the Board, which
shall have the power, at any time and from time to time, to remove members from
the Committee or to add members thereto. Vacancies on the Committee, however
caused, shall be filled by the Board.

           B. The Committee may interpret the Plan, prescribe, amend and rescind
any rules and regulations necessary or appropriate for the administration of the
Plan and make such other determinations and take such other action as it deems
necessary or desirable for the administration of the Plan and the protection of
the Company except as otherwise reserved to the Board or the stockholders of the
Company. Without limiting the generality of the foregoing, the Committee, in its
discretion, may treat all or any part of any period during which a Participant
is on military duty or on an approved leave of absence from the Company as a
period of employment of such Participant by the Company for purposes of accrual
of his rights under his Option. In addition, the Committee shall have the
specific authority to grant Options with different terms to different
Participants and shall further have the specific authority to require a minimum
holding period between the grant and exercise of any Option, to determine that
the Options granted to a Participant may be exercised only in installments, to
accelerate the vesting of any Option and to specify such conditions precedent to
the exercise of any Option as the


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Committee may deem advisable. The Committee may at any time, with the consent of
the Participant, at its sole discretion, cancel any Option and issue to the
Participant a new Option for any equivalent or lesser number of Shares, and at a
lesser Option Price. Any interpretation, determination or other action made or
taken by the Committee shall be final, binding and conclusive.

           C. No member of the Committee shall be liable for any action taken or
omitted or determination made in good faith with respect to the Plan or any
Option granted under the Plan.

      6. SHARES SUBJECT TO PLAN. Options may be granted by the Company from time
to time to purchase an aggregate of 6,000,000 Shares subject to adjustment as
provided in Item 11 below. The Shares issued upon exercise of Options granted
under the Plan may be authorized and unissued Shares or Shares repurchased by
the Company. If any Option granted under the Plan shall terminate, expire or,
with the consent of the Participant, be canceled as to any Shares, new Options
may thereafter be granted covering any such Shares. The Options granted to a
Participant in any single fiscal year shall not cover more than the total number
of Shares available for grant under the Plan, subject to adjustment as provided
in Item 11 below.

      7. ELIGIBILITY. Options may be granted to those Employees and
Non-Employees of the Company selected by the Committee in its sole discretion
from time to time who have and exercise key management functions for the Company
or who discharge other responsibilities important to the success of the Company.
Notwithstanding anything to the contrary in this Plan, Options may be granted to
a director who is a member of the Committee if otherwise exempt from Section
16(b) of the Exchange Act pursuant to Rule 16b-3, SEC interpretations thereof or
any subsequently promulgated rule or regulation. The granting of an Option to
any Participant shall neither entitle such Participant to, nor disqualify such
Participant from participation in any future Option grants.

      8. GRANT OF OPTIONS. The Committee shall have the authority, subject to
the terms of the Plan, to: (a) determine and designate from time to time those
key employees (including officers), consultants and directors to whom Options
are to be granted; (b) determine the number of Shares subject to each Option;
(c) determine the duration of the exercise period for any Option; (d) determine
that the Options granted to a Participant may be exercised only in installments;
and (e) specify such other terms and conditions of each Option as the Committee
in its sole discretion deems advisable. The date of grant of an Option under the
Plan will be the date on which the Option is awarded by the Committee.

      9. TERMS AND CONDITIONS OF OPTIONS. Each Option shall be evidenced by an
Option Agreement which shall contain such terms and conditions consistent with
the provisions of the Plan as may be approved by the Committee and shall be
signed by an officer of the Company and the Participant. Each Option granted
under the Plan shall be subject to such terms and conditions as follows:


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      TERMS OF NQSO'S. NQSO's granted hereunder shall be subject to the terms
and conditions contained in subparagraphs A - D below, and to such other terms
and conditions as the Committee may deem appropriate.

           A. Option Period. Each NQSO Option Agreement shall specify the period
during which the Option thereunder is exercisable (which shall not exceed ten
years from the date of grant) and shall provide that the NQSO shall expire at
the end of such period.

           B. Option Price. The Option Price per Share shall be determined by
the Committee at the time any NQSO is granted. Such price shall be subject to
adjustments as provided in Item 11.

           C. Period to Exercise Option. Any NQSO granted hereunder may, prior
to its expiration or termination, be exercised from time to time, in whole or in
part, up to the total number of Shares with respect to which it shall have then
become exercisable. An NQSO granted hereunder may become exercisable in
installments as determined by the Committee; provided, however, that if the
Committee grants an Option exercisable in more than one installment, and if the
employment of an Employee-Participant holding such Option is terminated, then
unless the Option Agreement provides otherwise, the Option shall be exercisable
only as to such number of Shares as to which the Participant had the right to
exercise the Option on the date of termination of employment.

           D. Restrictions on Grants to Non-Employee Directors. Any NQSO granted
hereunder to a Non-Employee Director shall provide that the Shares received upon
exercise of the Option may not be disposed of before the first day following the
six month anniversary of the date the Option was granted.

      10. EXERCISE OF OPTION. The exercise of any Option under the Plan shall be
subject to the provisions of Paragraphs A, B and C below.

           A. Method of Exercising Option. Any Option granted hereunder or any
portion thereof (in whole Shares only) may be exercised by the Participant by
(i) delivering to the Company at its main office (attention its Secretary,
Assistant Secretary or Chief Financial Officer) written notice which shall set
forth the Participant's election to exercise a portion or all of his Option, the
number of Shares with respect to which the Option rights are being exercised,
and such other representations and agreements as may be required by the Company
to comply with applicable securities laws and loan agreements to which the
Company is a party, and (ii) paying in full the Option Price of the Shares
purchased. Upon receipt of such notice and payment, the Company shall issue and
deliver to the Participant a certificate for the number of Shares with respect
to which Options were so exercised. In the Option Agreement, the Committee may
require the exercise of Options by any Participant to comply with the
requirements of the SEC.

           B. Payment of Option Price. The Option Price of the Shares as to
which an Option is exercised shall be paid in full to the Company at the time of
exercise. The payment may be made either in cash or its equivalent or, where
permitted by law and approved by the Committee in its sole discretion: (i) by
delivery of a promissory note on terms and conditions acceptable to the
Committee; (ii) by cancellation of indebtedness of the Company to the
Participant; (iii) by surrender of shares of Common Stock of the Company having
a Fair Market


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Value equal to the exercise price of the Option; (iv) by instructing the Company
to withhold shares otherwise issuable pursuant to an exercise of an Option
having a Fair Market Value equal to the exercise price of the Option (including
withheld shares); (v) by waiver of compensation due or accrued to the
Participant for services rendered; or (vi) by any other means approved by the
Committee. Participants who are not Employees shall not be entitled to purchase
Shares with a promissory note unless the note is adequately secured by
collateral other than the Shares so purchased.

                  Notwithstanding anything to the contrary above, the Committee,
in its discretion, may suspend or terminate the right of participants to pay in
a form other than cash should the Committee deem such action to be in the best
interests of the Company.

           C. Withholding Taxes. The Company may, in its discretion, require a
Participant to pay to the Company at the time of exercise the amount that the
Company deems necessary to satisfy its obligation to withhold federal, state or
local income or other taxes incurred by reason of the exercise. Where the
exercise of an Option does not give rise to an obligation to withhold federal
income taxes on the date of exercise, the Company may, in its discretion,
require a Participant to place Shares purchased under the Option in escrow for
the benefit of the Company until such time as federal income tax withholding is
required on amounts included in the gross income of the Participant as a result
of the exercise of an Option or the disposition of Shares acquired pursuant
thereto. At such time, the Company, in its discretion, may require the
Participant to pay to the Company the amount that the Company deems necessary to
satisfy its obligation to withhold federal, state or local income or other taxes
incurred by reason of the exercise of the Option or the disposition of Shares,
in which case the Shares will be released from escrow to the Participant.

           D. No Fractional Shares. Notwithstanding anything herein to the
contrary, no fractional Shares may be issued under the Plan.

      11. CAPITAL ADJUSTMENTS. The number and price of Shares covered by each
Option, the number of Shares that become exercisable at any one time and the
total number of Shares that may be optioned and sold under the Plan shall be
proportionately adjusted to reflect any Share dividend, Share split or Share
combination or any recapitalization of the Company. Except as expressly provided
in this Item 11, the Participant shall have no rights by reason of any change in
the Shares of the Company. The grant of an Option pursuant to this Plan shall
not affect in any way the right or power of the Company to make adjustments,
reclassifications, reorganizations or changes of its capital or business
structure or to merge, consolidate, dissolve, liquidate, sell or transfer all or
any part of its business or assets. The Committee shall have the sole discretion
to make all interpretations and terminations required under this Item to the
extent it deems equitable and appropriate.

      12. EFFECT OF CHANGE OF CONTROL. Except as otherwise set forth in the
applicable Option Agreement, every Option granted under this Plan shall become
immediately exercisable as to all of the Common Shares subject to such Option
upon the first to occur of: (a) a Change of Control with respect to the Company,
or (b) approval by the stockholders of the Company of a transaction which would
constitute a Change of Control.


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      13. COMPANY'S RIGHT TO REDEEM OPTIONS. Any provision of this Plan to the
contrary notwithstanding, in the event the Company is a party to an agreement to
sell all or substantially all of its assets, a merger or other reorganization,
all outstanding Options shall be subject to the agreement of sale, merger or
reorganization which may provide, without limitation, for the assumption of
outstanding Options by the surviving corporation or its Parent, for their
continuation by the Company (if it is the surviving corporation), for
accelerated termination and redemption of Options in stock or cash, or for other
arrangements which provide the Participant with a per share economic benefit at
least equal to the difference between the fair market value (as reasonably
determined by the Board) of the consideration received for each Share in the
transaction and the Option Price.

      14. RESERVATION OF SHARES. The Company, during the term of any Options
granted hereunder, will at all times reserve and keep available, and will seek
to obtain from any regulatory body having jurisdiction any requisite authority
in order to issue and sell such number of Shares as shall be sufficient to
satisfy the requirements of the Options granted under the Plan. If, in the
opinion of the Company's counsel, the issuance or sale of any Shares hereunder
shall not be lawful for any reason, including the inability of the Company to
obtain from any regulatory body having jurisdiction authority deemed by such
counsel to be necessary for such issuance or sale, the Company shall not be
obligated to issue or sell any such Shares.

      15. SECURITIES LAWS. Upon the exercise of an Option at a time when there
is not in effect under the Securities Act of 1933, as amended (the "Act"), a
current registration statement relating to the Shares to be received upon such
exercise, the Participant shall represent and warrant in writing to the Company
that the Shares purchased are being acquired for investment and not with a view
to the distribution thereof and shall agree to the imposition of a legend on the
certificate or certificates representing said Shares in substantially the
following form and such other restrictive legends as are required or advisable
under the provision of any applicable laws:

            This share certificate and the Shares represented hereby have not
            been registered under the Securities Act of 1933, as amended (the
            "Act"), nor under the securities laws of any state and shall not be
            transferred at any time in the absence of (i) an effective
            registration statement under the Act and any other applicable state
            law with respect to such Shares at such time; or (ii) an opinion of
            counsel satisfactory to the Company and its counsel to the effect
            that such transfer at such time will not violate the Act or any
            applicable state securities laws; or (iii) a "no action" letter from
            the Securities and Exchange Commission and a comparable ruling from
            any applicable state agency with respect to such state's securities
            laws.

            No Shares shall be issued or sold upon the exercise of any Option
unless and until (i) the full amount of the purchase price has been paid as
provided in Item 10 hereof and (ii) the then applicable requirements of the Act,
the applicable securities laws of any other jurisdiction, as any of the same may
be amended, the rules and regulations of the SEC and any other regulations of
any securities exchange on which the Shares may be listed shall have been fully
complied with and satisfied.


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      16. TRANSFERABILITY AND OPTIONS. No Option shall be assignable or
transferable by a Participant except by will or by the laws of descent and
distribution. Any distributee by will or by the laws of descent and distribution
shall be bound by the provisions of the Plan. During the life of a Participant,
the Option shall be exercisable only by such Participant. Any attempt to assign,
pledge, transfer, hypothecate or otherwise dispose of an Option and any levy,
execution, attachment or similar process on an Option shall be null and void.

      17. NO RIGHTS AS STOCKHOLDERS. A Participant shall not have any rights as
a stockholder with respect to any Shares covered by any Option granted hereunder
until the issuance of a certificate for such Shares. No adjustment shall be made
on the issuance of a share certificate to a Participant as to any distributions
or other rights for which the record date occurred prior to the date of issuance
of such certificate.

      18. INDEMNIFICATION AND EXCULPATION. Each person who is or shall have been
a member of the Management Committee or of the Committee shall be indemnified
and held harmless by the Company against and from any and all loss, costs,
liability or expense that may be imposed upon or reasonably incurred by him in
connection with or resulting from any claim, action, suit or proceeding to which
he may be or become involved by reason of any action taken or failure to act
under the Plan and against and from any and all amounts paid by him in
settlement thereof (with the Company's written approval) or paid by him in
satisfaction of a judgment in any such action, suit or proceeding, except a
judgment in favor of the Company based upon a finding of his lack of good faith;
subject, however, to the condition that upon the institution of any claim,
action, suit or proceeding against him, he shall in writing give the Company an
opportunity, at its expense, to handle and defend the same before he undertakes
to handle and defend it on his own behalf. The foregoing right of
indemnification shall not be exclusive of any other right to which such person
may be entitled as a matter of law or otherwise, or any power that the Company
may have to indemnify him or hold him harmless. Each member of the Board or of
the Committee and each officer and employee of the Company shall be fully
justified in relying or acting in good faith upon any information furnished in
connection with the administration of the Plan by any appropriate person or
persons other than himself. In no event shall any person who is or shall have
been a member of the Board or of the Committee, or an officer or employee of the
Company, be held liable for any determination made, or other action taken, or
any omission to act in reliance upon any such information as referred to in the
preceding sentence, or for any action (including the furnishing of information)
taken, or any omission to act, when any such determination, action or omission
is made in good faith.

      19. USE OF PROCEEDS. Proceeds from the sale of Shares pursuant to Options
granted under the Plan shall constitute general funds of the Company.

      20. AMENDMENT AND DISCONTINUANCE. The Board of the Company may terminate
or amend the Plan in any respect at any time, except that no action of the Board
may alter or impair a Participant's rights under any outstanding Option without
his consent.

      21. TERM OF PLAN. The Plan shall be effective as of the date of the
adoption of the Plan by the Board and stockholders of the Company and shall
expire on December 19, 2012, unless sooner terminated as provided in Item 20
hereof.


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      22. GENERAL. Except as the same may be governed by the Code and any
applicable federal securities laws, the Plan and any Options granted hereunder
shall be governed by and construed in accordance with the laws of the State of
Delaware. The granting of an Option shall impose no obligation upon the
Participant to exercise such Option. As herein used, the singular number shall
include the plural, the plural the singular, and the use of any gender shall be
applicable to all genders, unless the context or use shall fairly require a
different construction. Section or paragraph headings are employed herein solely
for convenience of reference, and such headings shall not affect the validity,
meaning or enforceability of any provision of the Plan. All references herein to
"Item" or "paragraph" shall mean the appropriately numbered Item or paragraph of
the Plan except where reference is made to the Code or any other specified law
or instrument.

AS APPROVED BY THE BOARD OF DIRECTORS OF THE COMPANY ON DECEMBER 19, 2002.


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