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                                                                 Exhibit 10.1.20
                        ADVANCED TELECOMMUNICATIONS, INC.

                             FIRST AMENDMENT TO THE

              SECOND AMENDED AND RESTATED STOCK OPTION PLAN OF 1996

                               (November 19, 1999)

RECITALS:

A.       The Advanced Telecommunications, Inc. Stock Option Plan of 1996 (the
         "Plan") as originally adopted by the Board ofDirectors of Advanced
         Telecommunications, Inc. (the "Company'~) on July 1, 1996, and as
         amended and restated to date, is now in full force and effect.

B.       On May 27, 1999, the Board of Directors approved a 60 to 1 stock split
         of the Company's common and preferred stock, which stock split became
         effective upon the filing of the Fifth Articles ofAmendment to the
         Articles oflncorporation with the Minnesota Secretary of State on July
         15, 1999.

C.       Effective September 30, 1999, the Company was reincorporated as a
         Delaware corporation by merger of the Company with and into a
         wholly-owned Delaware subsidiary. Pursuant to the merger, each share of
         the Company's Class A common stock was converted into a share of the
         surviving Delaware corporation's common stock.

D.       After giving effect to the stock split and the reincorporation, the
         total number of shares of the Company's common stock set aside for
         issuance upon exercise of options granted under the Plan was 2,400,000.

E.       On November 17, 1999, the Board of Directors unanimously approved an
         increase in the number of shares of the Company's common stock set
         aside for issuance upon exercise of options granted under the Plan from
         2,400,000 to 4,400,000.

F.       By Written Consent effective November 19, 1999, stockholders holding a
         majority of the issued and outstanding capital stock of the Company
         approved the increase in the number of shares of the Company's common
         stock set aside for issuance upon exercise of options granted under the
         Plan from 2,400,000 to 4,400,000.

NOW THEREFORE, in consideration of the foregoing, the Plan is amended as
follows:

1.       Section 3 of the Plan is amended to read in its amended form as
         follows:

         "3. AUTHORITY TO GRANT OPTIONS.

         Subject to adjustment as provided in Section 11 of the Plan, the Board
         of Directors of


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                        ADVANCED TELECOMMUNICATIONS, INC.

         the Company, or the Committee, if created, may from time to time in its
         discretion grant to Eligible Recipients of the Company or its
         Subsidiary Corporations (whether now existing or hereafter acquired)
         options under which up to, but not more than, an aggregate of Four
         Million Four Hundred Thousand (4,400,000) shares of the Company's
         Common Stock, $0.01 par value per share, may be issued, such options
         to contain the terms and be subject to the conditions hereinafter
         provided.

                  The shares shall be made available from authorized and
         unissued common stock or from Common Stock issued and held in the
         Treasury of the Company, as shall be determined by the Board
         of Directors."

2.       This First Amendment to the Advanced
         Telecommunications, Inc. Second
         Amended and Restated Stock Option              Chief
         Plan of 1996 is effective as of                Executive
         November 19, 1999.


ATTEST:

    David L. Mitchell, Secretary


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                        ADVANCED TELECOMMUNICATIONS, INC.

                        ADVANCED TELECOMMUNICATIONS, INC.
              SECOND AMENDED AND RESTATED STOCK OPTION PLAN OF 1996
                         (DATED AS of JANUARY 25, 1999)

1.       PURPOSE.

                  This Stock Option Plan (the "Plan") is intended to enable
Advanced Telecommunications, Inc. (the "Company") and its Subsidiary
Corporations (now existing or hereinafter acquired or created) to attract and
retain persons of ability to perform services for the Company and its Subsidiary
Corporations by providing an incentive to such individuals through equity
participation in the Company and by rewarding such individuals who contribute to
the achievements by the Company of its economic objectives. The purpose of the
Plan Will be accomplished through the granting of stock options as herein
provided, which may be issued in a form to qualify as "incentive stock options"
within the meaning of the provisions of Section 422 of the Internal Revenue Code
of 1986, as amended ("Incentive Options"), or as stock options not within the
meaning of such section ("Nonqualified Option"), in the discretion of the Board
of Directors of the Company or the Committee.

                  This Plan amends and restates in its entirety the Company's
Incentive Stock Option Plan of 1996.

2.       DEFINITIONS.

                  Whenever used in this Plan, the following terms shall have the
respective meanings set forth below, unless the context clearly requires
otherwise, and when the defined meaning is intended, the term is capitalized:

                  (a)      "Code" shall mean the Internal Revenue Code of 1986,
         as amended.

                  (b)      "Committee" shall mean the Committee provided for by
         Section 4 hereof.

                  (c)      "Parent Corporation" shall have the meaning set forth
         in Code Section 424(e), with the Company being treated as the employer
         corporation for purposes of said definition.

                  (d)      "Subsidiary Corporation" shall have the meaning set
         forth in Code Section 424(f), with the Company being treated as the
         employer corporation for purposes of said definition.

                  (e)      "Significant Shareholder" means an individual who
         within the meaning of Code Section 422(b)(6) owns stock possessing more
         than ten percent


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                        ADVANCED TELECOMMUNICATIONS, INC.
         (10%) of the total combined voting power of all classes of stock of
         Subsidiary Corporation. In determining whether an individual is a
         Significant Shareholder, an individual shall be treated as owning stock
         owned by certain relatives of the individual and certain stock owned by
         corporation in which the individual is a shareholder, partnerships in
         which the individual is a partner, and estates or trusts of which the
         individual is a beneficiary, all as provided in Code Section 424(d).

                  (f)      "110% Five Year Option" means an option (i) that has
         an option price of at least 110% of the price of the stock subject to
         such option on the date such option is granted, and (ii) that by its
         terms is not exercisable after the expiration of five (5) years from
         the date such option is granted.

                  (g)      "Participant" means an Eligible Recipient who
         receives one or more options under the Plan.

3.       AUTHORITY TO GRANT OPTIONS.

                  The Board of Directors of the Company, or the Committee, if
created, may from time to time in its discretion grant to Eligible Recipients of
the Company or its Subsidiary Corporations (whether now existing or hereafter
acquired) options under which up to, but not more than, an aggregate of Forty
Thousand (40,000) shares of the Company's Class A common stock, $.0l par value
(hereinafter referred to as "Common Stock") may be issued, such options to
contain the terms and be subject to the conditions hereinafter provided.

                  The shares shall be made available from authorized and
unissued common stock or from Common Stock issued and held in the Treasury of
the Company, as shall be determined by the Board of Directors.

4.       ADMINISTRATION.

                  At the discretion of the Board of Directors of the Company,
this Plan may be administered by a Committee which shall be an executive
committee of the Board of Directors of the Company consisting of not less than
two members of the Board of Directors who are nc employees of the Company. Such
Committee shall have full power and authority, subject to the limitations of the
Plan and the specific terms of any options granted under this Plan, to construe
interpret and administer this Plan and to make determinations and, by resolution
or resolution providing for the creation and issuance of any such option, to fix
the terms upon which, the time ( times at or within which, and the price or
prices at which any such shares may be purchased from the Company upon the
exercise of such option, which terms, time or times and price or prices shall in
every case, be set forth or incorporated by reference in the instrument or
instruments evidencing such option, and shall be consistent with the provisions
of this Plan. The Board of Directors may from time to time remove members from,
or add members to, the Committee. Vacancies on the Committee, howsoever caused,
shall be filled by the Board of Directors. The Committee shall select one of its
members as


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                        ADVANCED TELECOMMUNICATIONS, INC.
Chairman, and shall hold meetings at such times and places as the Chairman
may determine. A majority of the Committee at which a quorum is present, or
acts reduced to approved in writing by all of the members of the Committee,
shall be the valid acts of the Committee. The Board of Directors shall have
all of the enumerated powers of the Committee, but shall not be limited to
such powers. No member of the Board of Directors or the Committee shall be
liable for any action or determination made in good faith with respect to the
Plan or any option granted under it.

5.       ELIGIBILITY.

                  Employees, directors, consultants and independent contractors
of the Company or of a Subsidiary Corporation (now existing or hereafter created
or acquired) shall be eligible to participate in this Plan and will herein be
referred to as "Eligible Recipients."

6.       SIGNIFICANT SHAREHOLDERS.

                  No option shall be granted hereunder to an individual who, at
the time the option is granted, is a Significant Shareholder unless the option
is a 110% Five-Year Option or is a Nonqualified Option.

                  An option granted to a Significant Shareholder in violation of
the provisions of this section shall be void.

7.       ALLOTMENT OF SHARES.

                  Options may be allotted to such Eligible Recipients, in such
amounts, consistent with the provisions of the Code, as the Committee or Board
of Directors in its discretion may from time to time determine.

8.       TERM OF PLAN.

                  No option shall be granted pursuant to this Plan after the
expiration (the "Expiration Date") often (10) years from the earlier of the date
of its adoption prior to the Expiration Date by the Board of Directors or its
approval by shareholders, but options granted prior to the Expiration Date may
be exercisable after the Expiration Date.

9.       TERMS AND CONDITIONS OF OPTIONS.

                  Subject to the following provisions (which may be amended as
provided in Section 14 hereof), all options granted pursuant to this Plan shall
be in such form and subject to such terms and conditions, including vesting
provisions, as the Committee or the Board of Directors, in its discretion, may
from time to time determine, provided, however, that with regard to any options
intended to qualify as "incentive stock options," such terms and conditions must
be consistent with the provisions of Code Section 422.


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                        ADVANCED TELECOMMUNICATIONS, INC.

                  (a)      OPTION PRICE. The option price per share with respect
         to each option which is an Incentive Option shall be not less than the
         fair market value of the Common Stock (110% of the fair market value if
         granted to an individual who is a Significant Shareholder at the date
         of grant) on the date the option is granted.

                  (b)      PERIOD OF OPTION. In no event shall an option be
         exercisable after the expiration of ten (10) years from the date of
         grant thereof (five [5] years from the date of grant if granted to an
         individual who is a Significant Shareholder at the date of grant), and
         each option shall so provide by its terms.

                  (c)      PAYMENT. Payment for all shares shall be made at the
         time that an option, or any part thereof, is exercised, and no shares
         shall be issued until full payment therefor has been made. Payment
         shall be made in cash or at the discretion of the Board of Directors in
         stock of the Company, or in such other form which is acceptable to the
         Board of Directors and, in the case of Incentive Options, which does
         not prevent such options from qualifying for treatment as an "incentive
         stock option" within the meaning of the Code.

                  (d)      EXERCISE OF OPTION. Unless an option is terminated as
         provided hereunder or expires by its terms, a Participant may exercise
         his or her vested options in whole or in part at any time or from time
         to time in accordance with the terms and conditions of this Plan.

                  (e)      NON-TRANSFERABILITY OF OPTIONS. During a
         Participant's lifetime, an option, by its terms, shall be exercisable
         only by such Participant and shall not be transferable except by will
         or the laws of descent and distribution.

                  (f)      DEATH OF OPTION HOLDER. Upon the death of a
         Participant, such Participant's option privileges shall appy to those
         shares which were immediately purchasable by the Participant at the
         time of death, and such privileges shall expire unless exercised by the
         executor or administrator of the Participant's estate, or by a person
         who acquired the right to exercise such option by bequest or
         inheritance or by reason of the Participant's death, within one (1)
         year after the date of death or such shorter period as may be
         determined by the Committee or the Board of Directors; provided,
         however, that in any event the option may not be exercised after the
         expiration of term (10) years from the date the option is granted (five
         [5] years in the case of 110% Five Year Option), or such shorter
         periods as may be provided in the instrument granting the option.

                  (g)      RESTRICTION ON ISSUANCE OF SHARES. The Company shall
         not be obligated to sell or issue any shares pursuant to any stock
         option unless the shares with respect to which the option is being
         exercised are at that time effectively registered or exempt from
         registration under the Securities Act of 1933, as amended, and any
         other applicable laws. The Company may require (i) as a condition to
         the sale of shares on the exercise of any option, that the person
         exercising such


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                        ADVANCED TELECOMMUNICATIONS, INC.
         option give to the Company representations that the Participant (a) is
         acquiring such shares without a view to the distribution thereof,
         and (b) accepts as a condition before any transfer in connection with
         the resale of such shares, the Participant will obtain the written
         opinion of counsel for the Company, or other counsel acceptable to
         the Company, that such shares may be transferred; and (ii) that any
         stock certificate issued under this Plan have an appropriate legend
         inscribed thereon.

                  (h)      RIGHTS AS A STOCKHOLDER. A Participant shall have no
         rights as a stockholder with respect to any shares covered by an option
         until the date of issuance of a stock certificate to such Participant
         for such shares.

                  (i)      TIME OF GRANTING OPTION. Nothing contained in the
         Plan shall constitute the granting of any option hereunder. An option
         shall be granted only pursuant to a resofution of the Committee or the
         Board of Directors of the Company.

                  (j)      TERMINATION OF SERVICE. In the event of termination
         of service of a Participant, other than (a) by reason of death, or (b)
         by the Company for cause, defined as set forth in the instrument
         granting the option, the Participant may exercise such portion of the
         option as was exercisable by such Participant at the date of
         termination of service at any time within three (3) months (one (1)
         year after death in the case of a Participant whose service terminates
         by reason of death) but in no event after ten (10) years (five [5]
         years in the case of a 110% Five Year Option) from the date such option
         was granted to such Participant, or such shorter periods as may be
         provided in the instrument granting the options. Options not exercised
         within the applicable period, shall terminate. In the event a
         Participant's service is terminated by the Company for cause, any
         option or options held by the Participant under the Plan, to the extent
         not exercised before such termination, shall forthwith terminate. A
         change of duties or position within the Company or an assignment of
         employment or service in a Subsidiary Corporation of the Company shall
         not be considered a termination of service for the purposes of this
         Plan. The written option agreements may contain such provisions as the
         Committee or the Board of Directors of the Company shall approve with
         reference to the effect of approved leaves of absence upon termination
         of service.

                  (k)      $100,000 DOLLAR LIMITATION. With respect to Incentive
         Options, the aggregate fair market value (determined as of the time the
         option is granted) of the stock with respect to which options of any
         Participant are exercisable for the first time in any calendar year
         (including options granted under this Plan and under any other
         incentive stock option plan of the Company or any Parent Corporation or
         Subsidiary Corporation of the Company) shall not exceed One Hundred
         Thousand Dollars ($100,000), or any limit as may be imposed by the Code
         from time to time.

10.      RIGHT TO PROPERTY AT EXERCISE.

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                        ADVANCED TELECOMMUNICATIONS, INC.

                  If approved by the Board of Directors of the Company, a
Participant may be granted the right to receive cash or property from the
Company at the time such Participant exercises an option granted hereunder;
provided, however, that if property other than cash is to be transferred to
the Participant, Section 83 of the Code must apply to the property so
transferred, as provided by Code Section 422(c)(4).

11.      ADJUSTMENT IN EVENT OF REORGANIZATION, ETC.

                  In the event of a reorganization, recapitalization, stock
split, stock dividend, combination of shares, merger, consolidation, rights
offering, or any other change in the corporate structure or shares of the
Company, the Board of Directors of the Company or the Committee shall make such
adjustment, if any, as may be appropriate in the number and kind of shares
authorized by this Plan, or in the number, option price and kind of shares
authorized by this Plan, or in the number, option price and kind of shares
covered by the options granted. Any option granted hereunder may provide that,
at the option of the Board of Directors or the Committee, (a) upon the
dissolution or liquidation of the Company, all (or portions of) options then
issued and outstanding shall either terminate or become immediately exercisable
in full, without regard to the period of continuous service to the Company
subsequent to the granting of such option, and (b) upon any merger,
consolidation, or other form of reorganization in which the Company is not the
surviving corporation, all options then issued and outstanding shall either
terminate or be immediately exercisable in full, without regard to the period of
continuous service to the Company subsequent to the granting of the options,
unless the surviving corporation or its parent corporation shall issue
substitute options for shares for the surviving corporation or its parent
corporation on similar terms and conditions as the options then outstanding.

12.      REALLOCATION OF LAPSED OPTIONS.

                  Shares covered by options which have lapsed or have terminated
may be subject to new option grants under the Plan.

13.      GOVERNMENTAL REGULATIONS.

                  This Plan, and the grant and exercise of options hereunder,
shall be subject to all applicable rules and regulations of the Federal
govemment and other applicable governmental authorities.

14.      TERMINATION AND AMENDMENT OF PLAN AND OPTIONS.

                  The Board of Directors of the Company may from time to time
alter, amend, modify or terminate this Plan, as it shall deem advisable,
provided, however, that the Board of Directors may not, without prior approval
of the holders of a majority of the issued and outstanding stock of the Company,
change the definition of persons eligible to participate in the Plan or increase
the maximum number of shares which may be issued pursuant to options granted
under the Plan, except on account of adjustments under Section 11. The Board of
Directors of the Company or the


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                        ADVANCED TELECOMMUNICATIONS, INC.

Committee may amend, modify, or terminate options, provided that such
Participant's consent to such actions shall be required unless such actions are
not materially adverse to the Participant.

15.      CONTINUED SERVICE.

                  Nothing in this Plan or in any option agreement under this
Plan shall confer on any individual any right to continue in the employ or
service of the Company or its Subsidiary Corporations or affect in any way the
right of the Company or its Subsidiary Corporations to terminate his or her
employment or service at any time.

16.      EFFECTIVE DATE OF PLAN.

                  The Plan shall become effective upon the adoption thereof by
the Board of Directors of the Company. However, the Plan shall be submitted to
the stockholders of the Company for their approval within a period of not to
exceed twelve (12) months from the date of its adoption by the Board of
Directors.

17.      COMPLIANCE WITH CODE.

                  Options granted hereunder may be Incentive Options or
Nonqualified Options.

18.      NO OBLIGATION TO EXERCISE OPTION.

                  The granting of an option shall impose no obligation upon the
Participant to exercise such option.

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