<PAGE>

                                                                       Page 1


                          1993 NON-EMPLOYEE DIRECTOR PLAN OF
                               U.S. LONG DISTANCE CORP.

    1.   PURPOSE.  The purpose of this Plan is to advance the interests of U.S.
Long Distance Corp., a Delaware corporation (the "Company"), by providing an
additional incentive to attract and retain qualified and competent directors,
upon whose efforts and judgment the success of the Company is largely dependent,
through the encouragement of stock ownership in the Company by such persons.

    2.   DEFINITIONS.  As used herein, the following terms shall have the
meaning indicated:

         (a)  "Annual Director Fee" shall mean a fee payable annually to each
Eligible Person on the business day on or immediately after December 15 of each
year ("Payment Date"), at the election of the Eligible Person, in either cash of
$15,000 or an Option granted pursuant to Section 5 or partly in cash and partly
in an Option granted pursuant to Section 5.

         (b)  "Board" shall mean the Board of Directors of U.S. Long Distance
Corp. 

         (c)  "Committee" shall mean the committee, if any, appointed by the
Board pursuant to Section 12 hereof. 

         (d)  "Date of Grant" shall mean the date on which an Option is granted
to an Eligible Person pursuant to Section 4(c) hereof. 

         (e)  "Director" shall mean a member of the Board. 

         (f)  "Eligible Person(s)" shall mean those persons who are Directors
of the Company and who are not employees of the Company or a Subsidiary. 

         (g)  "Fair Market Value" of a Share on any date of reference shall be
the closing price on the business day immediately preceding such date.  For this
purpose, the closing price of the Shares on any business day shall be (i) if the
Shares are listed or admitted for trading on any United States national
securities exchange, the last reported sale price of Shares on such exchange, as
reported in any newspaper of general circulation, (ii) if actual transactions in
the Shares are included in the National Association of Securities Dealers
Automated Quotation National Market System ("NASDAQ-NMS") or are reported on a
consolidated transaction reporting system, the last sales price of the Shares on
such system, (iii) if Shares are otherwise quoted on the National Association of
Securities Dealers Automated Quotation System ("NASDAQ"), or any similar system
of automated dissemination of quotations of securities prices in common use, the
mean between the closing high bid and low asked quotations for such day of
Shares on such system, (iv) if none of clause (i), (ii) or (iii) is applicable,
the mean between the high bid and low asked quotations for Shares as reported by
the 


<PAGE>

                                                                       Page 2

National Daily Quotation Service if at least two securities dealers have 
inserted both bid and asked quotations for Shares on at least five (5) of the 
ten (10) preceding days.

         (h)  "Internal Revenue Code" or "Code" shall mean the Internal Revenue
Code of 1986, as it now exists or may be amended from time to time.

         (i)  "Nonqualified Stock Option" shall mean an option that is not an
incentive stock option as defined in Section 422 of the Internal Revenue Code.

         (j)  "Option" (when capitalized) shall mean any option granted under
Section 4 or 5 of this Plan.

         (k)  "Optionee" shall mean a person to whom a stock option is granted
under this Plan or any successor to the rights of such person under this Plan by
reason of the death of such person.

         (l)  "Payment Date" shall have the meaning set forth in Section 2(a).

         (m)  "Plan" shall mean this 1993 Non-Employee Director Plan of U.S.
Long Distance Corp.

         (n)  "Share(s)" shall mean a share or shares of the common stock, par
value one cent ($0.01) per share, of the Company.

         (o)  "Subsidiary" shall mean any corporation (other than the Company)
in any unbroken chain of corporations beginning with the Company if, at the time
of the granting of the Option, each of the corporations other than the last
corporation in the unbroken chain owns stock possessing more than fifty percent
(50%) of the total combined voting power of all classes of stock in one of the
other corporations in such chain.

    3.   SHARES AND OPTIONS.  The maximum number of Shares to be issued
pursuant to Options under this Plan, including shares issued on the exercise of
Shares granted to Eligible Persons prior to the adoption of the Plan under the
Company outside the director option plan adopted in February 1991, shall be TWO
HUNDRED FIFTY THOUSAND (250,000) Shares.  Shares issued pursuant to Options
granted under this Plan may be issued from Shares held in the Company's treasury
or from authorized and unissued Shares.  If any Option granted under this Plan
shall terminate, expire, or be cancelled or surrendered as to any Shares, new
Options may thereafter be granted covering such Shares.  Any Option granted
hereunder shall be a Nonqualified Stock Option.

    4.   AUTOMATIC GRANT OF OPTIONS.  (a) Options shall automatically be
granted to Eligible Persons as provided in this Section 4.  Each Option shall be
evidenced by an option agreement (an "Option Agreement") and shall contain such
terms as are not inconsistent with this Plan or any applicable law.  Any person
who files with the 


<PAGE>

                                                                       Page 3

Committee, in a form satisfactory to the Committee, a written waiver of 
eligibility to receive any Option under this Plan shall not be eligible to 
receive any Option under this Plan for the duration of such waiver.

         (b)  The Options automatically granted to Directors under this Plan
shall be in addition to regular director's fees or other benefits with respect
to the Director's position with the Company or its Subsidiaries.  Neither the
Plan nor any Option granted under the Plan shall confer upon any person any
right to continue to serve as a Director.

         (c)  Options shall be automatically granted as follows:

              (i)  Each Director who is an Eligible Person shall automatically
    receive an Option for FIFTEEN THOUSAND (15,000) Shares on the date such
    Eligible Person is initially appointed or elected a Director of the
    Company, and such Option will vest as to FIVE THOUSAND (5,000) Shares on
    each of the first three anniversaries of the Date of Grant; and

              (ii) Each Director who is an Eligible Person will receive, on the
    first business date after the date of each annual meeting of stockholders
    of the Company, commencing with the annual meeting of stockholders
    immediately following the full vesting of any previously granted Director
    Option, an option to purchase FIFTEEN THOUSAND (15,000) Shares, and such
    Option will vest as to FIVE THOUSAND (5,000) Shares on each of the first
    three anniversaries of the Date of Grant.
         
         (d)  Any Option that may be granted pursuant to subparagraph (c) of
this Section 4 prior to the approval of this Plan by the stockholders of the
Company may be exercised on or after the Date of Grant subject to the approval
of this Plan by the stockholders of the Company within twelve (12) months after
the effective date of this Plan.  If any Optionee exercises an Option prior to
such stockholder approval, the Optionee must tender the exercise price at the
time of exercise and the Company shall hold the Shares to be issued pursuant to
such exercise until the stockholders approve this Plan.  If this Plan is
approved by the stockholders, the Company shall issue and deliver the Shares as
to which the Option has been exercised.  If this Plan is not approved by the
stockholders, the Company shall return the exercise price to the Optionee.

         (e)  Except for the automatic grants of Options under subparagraph (c)
of this Section 4 and grants of Options to Eligible Persons under Section 5
below, no Options shall otherwise be granted hereunder, and neither the Board
nor the Committee, if any, shall have any discretion with respect to the grant
of Options within the meaning of Rule 16b-3 promulgated under the Securities
Exchange Act of 1934, as amended, or any successor rule.

    5.   ELECTION WITH RESPECT TO ANNUAL DIRECTOR FEE.  Each Eligible Person
may 


<PAGE>

                                                                       Page 4

elect to receive the Annual Director Fee in cash or an Option or partly in
cash and partly in an Option.  Any election to receive an Option shall be in
writing and must be made no less than eleven (11) months prior to the Payment
Date in 1996, and thereafter such election shall be made not later than December
31 of each year with respect to the Annual Director Fee to be made on the
Payment Date in the subsequent year.  The election may not be revoked or changed
after it is made.  For purposes of this election and subject to Section 9, in
lieu of receipt of the Annual Director Fee in cash, as elected by the Eligible
Person, each $2 of cash compensation shall be converted into an Option, granted
as of the Payment Date, to purchase one (1) share of Common Stock.  If an
Eligible Person so elects to receive an Option, the Company shall promptly
deliver to such Eligible Person an Option Agreement.  To be eligible to receive
the Annual Director Fee, for any year, the Eligible Person must be a Director on
the Payment Date for that Annual Director Fee.  Any person who files with the
Committee, in a form satisfactory to the Committee, a written waiver of
eligibility to receive any Option under this Plan shall not be eligible to
receive any Option under this Plan for the duration of such waiver.

    6.   OPTION PRICE.  The option price per Share of any Option granted
pursuant to this Plan shall be one hundred percent (100%) of the Fair Market
Value per Share on the Date of Grant.

    7.   EXERCISE OF OPTIONS.  Options may be exercised at any time after the
date on which the Options, or any portion thereof, are vested until the Option
expires pursuant to Section 8; provided, however, that no Option shall be
exercisable prior to six (6) months from the Date of Grant.  An Option shall be
deemed exercised when (i) the Company has received written notice of such
exercise in accordance with the terms of the Option Agreement, (ii) full payment
of the aggregate option price of the Shares as to which the Option is exercised
has been made and (iii) arrangements that are satisfactory to the Committee in
its sole discretion have been made for the Optionee's payment to the Company of
the amount, if any, that the Committee determines to be necessary for the
Company to withhold in accordance with applicable federal or state income tax
withholding requirements.  Pursuant to procedures approved by the Committee, tax
withholding requirements, at the option of an Optionee, may be met by
withholding Shares otherwise deliverable to the Optionee upon the exercise of an
Option.  Unless further limited by the Committee in any Option Agreement, the
Option price of any Shares purchased shall be paid solely in cash, by certified
or cashier's check, by money order, with Shares (but with Shares only if
permitted by the Option Agreement or otherwise permitted by the Committee in its
sole discretion at the time of exercise) or by a combination of the above;
provided, however, that the Committee in its sole discretion may accept a
personal check in full or partial payment of any Shares.  If the exercise price
is paid in whole or in part with Shares, the value of the Shares surrendered
shall be their Fair Market Value on the date the Shares are received by the
Company.

    8.   TERMINATION OF OPTION PERIOD.  The unexercised portion of an Option
shall automatically and without notice terminate and become null and void at the
time of the 


<PAGE>

                                                                       Page 5

earliest to occur of the following:

         (a)  with respect to Options granted automatically pursuant to Section
4(c), thirty (30) days after the date that an Optionee ceases to be a Director
regardless of the reason therefor other than as a result of such termination by
death of the Optionee;

         (b)  with respect to Options granted automatically pursuant to
Section, 4(c), (y) one (1) year after the date that an Optionee ceases to be a
Director by reason of death of the Optionee or (z) six (6) months after the
Optionee shall die if that shall occur during the thirty-day period described in
Subsection 8(a); or

         (c)  the fifth (5th) anniversary of the Date of Grant of the Option.

    9.   ADJUSTMENT OF SHARES.  (a) If at any time while this Plan is in effect
or unexercised Options are outstanding, there shall be any increase or decrease
in the number of issued and outstanding Shares through the declaration of a
stock dividend or through any recapitalization resulting in a stock split-up,
combination or exchange of Shares, then and in such event: 

              (i)  appropriate adjustment shall be made in the maximum number
         of Shares then subject to being optioned under this Plan, so that the
         same proportion of the Company's issued and outstanding Shares shall
         continue to be subject to being so optioned; and

              (ii) appropriate adjustment shall be made in the number of Shares
         and the exercise price per Share thereof then subject to any
         outstanding Option, so that the same proportion of the Company's
         issued and outstanding Shares shall remain subject to purchase at the
         same aggregate exercise price. 

    In addition, the Committee shall make such adjustments in the Option price
and the number of shares covered by outstanding Options that are required to
prevent dilution or enlargement of the rights of the holders of such Options
that would otherwise result from any reorganization, recapitalization, stock
split, stock dividend, spin-off, combination of shares, merger, consolidation,
issuance of rights or any other change in capital structure of the Company.

         (b)  Except as otherwise expressly provided herein, the issuance by
the Company of shares of its capital stock of any class, or securities
convertible into shares of capital stock of any class, either in connection with
a direct sale or upon the exercise of rights or warrants to subscribe therefor,
or upon conversion of shares or obligations of the Company convertible into such
shares or other securities, shall not affect, and no adjustment by reason
thereof shall be made with respect to, the number of or exercise price of Shares
then subject to outstanding Options granted under this Plan.


<PAGE>

                                                                       Page 6

         (c)  Without limiting the generality of the foregoing, the existence
of outstanding Options granted under this Plan shall not affect in any manner
the right or power of the Company to make, authorize or consummate (i) any or
all adjustments, recapitalizations, reorganizations or other changes in the
Company's capital structure or its business; (ii) any merger or consolidation of
the Company; (iii) any issue by the Company of debt securities, or preferred or
preference stock that would rank above the Shares subject to outstanding
Options; (iv) the dissolution or liquidation of the Company; (v) any sale,
transfer or assignment of all or any part of the assets or business of the
Company; or (vi) any other corporate act or proceeding, whether of a similar
character or otherwise.

    10.  TRANSFERABILITY OF OPTIONS.  Each Option Agreement shall provide that
such Option shall not be transferable by the Optionee otherwise than by will or
the laws of descent and distribution or pursuant to a qualified domestic
relations order and that so long as an Optionee lives, only such Optionee or his
or her guardian or legal representative shall have the right to exercise the
related Option.

    11.  ISSUANCE OF SHARES.  No person shall be, or have any of the rights or
privileges of, a stockholder of the Company with respect to any of the Shares
subject to an Option unless and until certificates representing such Shares
shall have been issued and delivered to such person.  As a condition of any
transfer of the certificate for Shares, the Committee may obtain such agreements
or undertakings, if any, as it may deem necessary or advisable to assure
compliance with any provision of this Plan, any Option Agreement or any law or
regulation, including, but not limited to, the following:

              (i)  A representation, warranty or agreement by the Optionee to
         the Company, at the time any Option is exercised, that he or she is
         acquiring the Shares to be issued to him or her for investment and not
         with a view to, or for sale in connection with, the distribution of
         any such Shares; and 

              (ii) A representation, warranty or agreement to be bound by any
         legends that are, in the opinion of the Committee, necessary or
         appropriate to comply with the provisions of any securities law deemed
         by the Committee to be applicable to the issuance of the Shares and
         are endorsed upon the Share certificates.

    Share certificates issued to an Optionee who is a party to any stockholder
agreement or a similar agreement shall bear the legends contained in such
agreements.

    12.  ADMINISTRATION OF THE PLAN.  (a) This Plan shall be administered by a
stock option committee (the "Committee") consisting of not fewer than three (3)
members of the Board; provided, however, that if no Committee is appointed, the
Board shall administer this Plan and in such case all references to the
Committee shall be deemed to be references to the Board.  The Committee shall
have all of the powers of the Board 


<PAGE>

                                                                       Page 7

with respect to this Plan.  Any member of the Committee may be removed at any 
time, with or without cause, by resolution of the Board, and any vacancy 
occurring in the membership of the Committee may be filled by appointment by 
the Board.

         (b)  The Committee, from time to time, may adopt rules and regulations
for carrying out the purposes of this Plan.  The determinations and the
interpretation and construction of any provision of this Plan by the Committee
shall be final and conclusive.

         (c)  Any and all decisions or determinations of the Committee shall be
made either (i) by a majority vote of the members of the Committee at a meeting
or (ii) without a meeting by the written approval of a majority of the members
of the Committee.

         (d)  This Plan is intended and has been drafted to comply with Rule
16b-3, as amended, under the Securities Exchange Act of 1934, as amended.  If
any provision of this Plan does not comply with Rule 16b-3, as amended, this
Plan shall be automatically amended to comply with Rule 16b-3, as amended.

         (e)  This Plan shall not be amended more than once every six (6)
months, other than to comport with applicable changes to the Internal Revenue
Code, the Employee Retirement Income Security Act of 1974, as amended, or the
rules thereunder. 

    13.  INTERPRETATION.  (a) If any provision of this Plan is held invalid for
any reason, such holding shall not affect the remaining provisions hereof, but
instead this Plan shall be construed and enforced as if such provision had never
been included in this Plan.

         (b)  THIS PLAN SHALL BE GOVERNED BY THE SUBSTANTIVE LAWS OF THE STATE
OF DELAWARE, WITHOUT REFERENCE TO DELAWARE CONFLICT OF LAW PROVISIONS.

         (c)  Headings contained in this Plan are for convenience only and
shall in no manner be construed as part of this Plan.

         (d)  Any reference to the masculine, feminine or neuter gender shall
be a reference to such other gender as is appropriate.

    14.  SECTION 83(b) ELECTION.  If as a result of exercising an Option an
Optionee receives Shares that are subject to a "substantial risk of forfeiture"
and are not "transferable" as those terms are defined for purposes of Section
83(a) of the Code, then such Optionee may elect under Section 83(b) of the Code
to include in his gross income, for his taxable year in which the Shares are
transferred to such Optionee, the excess of the Fair Market Value of such Shares
at the time of transfer (determined without regard to any restriction other than
one which by its terms will never lapse), over 


<PAGE>

                                                                       Page 8

the amount paid for the Shares.  If the Optionee makes the Section 83(b) 
election described above, the Optionee shall (i) make such election in a 
manner that is satisfactory to the Committee, (ii) provide the Company with a 
copy of such election, (iii) agree to promptly notify the Company if any 
Internal Revenue Service or state tax agent, on audit or otherwise, questions 
the validity or correctness of such election or of the amount of income 
reportable on account of such election, and (iv) agree to such withholding as 
the Committee may reasonably require in its sole and absolute discretion.

    15.  EFFECTIVE DATE AND TERMINATION DATE.  The effective date of this Plan
or any amendment thereto is the date on which the Board adopted this Plan or
such amendment; provided, however, if this Plan is not approved by the
stockholders of the Company within twelve (12) months after the effective date,
then, in such event, this Plan and all Options granted pursuant to this Plan
shall be null and void.  This Plan shall terminate on September 17, 2000, and
any Option outstanding on such date will remain outstanding until it has either
expired or has been exercised.