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                               U.S. LONG DISTANCE CORP.
                                           
                           1990 EMPLOYEE STOCK OPTION PLAN
                                           
                                           
     1. PURPOSE. The purpose of this 1990 Stock Option Plan (hereinafter 
called the "Plan") is to further the success of U.S. Long Distance Corp., a 
Delaware corporation (hereinafter called the "Company"), and certain of its 
affiliates by making available Common Stock of the Company for purchase by 
certain officers and employees of the Company and its affiliates, and thus to 
provide an additional incentive to such individuals to continue in the 
service of the Company or its affiliates and to give them a greater interest 
as shareholders in the success of the Company.  Subject to compliance with 
the provisions of the Plan and the Internal Revenue Code of 1986, as amended, 
Incentive Stock Options are authorized by Section 422A of the Code and stock 
options which do not qualify under Section 422A of the Code are authorized 
and may be granted under the Plan.

     2. DEFINITIONS. As used in this Plan the following terms shall have the 
meanings indicated as follows:

     (a)  "Board" means the Board of Directors of the Company.
                    
     (b)  "Code" means the Internal Revenue Code of 1986, as amended.
                    
     (c)  "Committee" means the Committee administering the Plan described    
in Paragraph 3 hereof.
                    
     (d)  "Common Stock" means the Company's Common Stock, par value $.01
per share.
                    
     (e)  "Date of Grant" means the date on which an option is granted under 
a written option agreement executed by the Company and a Participant pursuant 
to the Plan.
                    
     (f)  "Disinterested Person" means a "disinterested person" in Rule 16b-3 
promulgated under the Exchange Act or any successor provision.
                    
     (g)  "Effective Date" means the effective date of this Plan specified in 
Paragraph 13 hereof.
                    
     (h)  "Exchange Act" means the Securities Exchange Act of 1934, as it may 
be amended from time to time.
                    
     (i)  "Incentive Stock Option" means an option qualifying under Section 
422A of the Code.

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     (j)  "Parent" means a parent corporation of the Company as defined in 
Section 425(e) of the Code.
                    
     (k)  "Participants" means the employees and officers of the Company, its 
Subsidiaries and its Parents and those directors of the Company who are also 
employees of the Company or its subsidiaries.
                    
     (l)  "Subsidiary" means a subsidiary corporation of the Company as 
defined in Section 425(f) of the Code.

     3. ADMINISTRATION OF THE PLAN. The Board of Directors of the Company 
shall appoint a committee (the "Committee") comprised of two directors to 
administer the Plan.  Only directors who are Disinterested Persons shall be 
eligible to serve as members of the Committee.  The Committee shall report 
all action taken by it to the Board, which shall review and ratify or approve 
those actions that are by law required to be so reviewed and ratified or 
approved by the Board.  The Committee shall have full and final authority in 
its discretion, subject to the provisions of the Plan, to determine the 
Participants to whom, and the time or times at which, options shall be 
granted and the number of shares and purchase price of Common Stock covered 
by each option; to construe and interpret the Plan and any agreements made 
pursuant to the Plan; to determine the terms and provisions (which need not 
be identical or consistent with respect to each Participant) of the 
respective option agreements and any agreement ancillary thereto including, 
but without limitation, terms covering the payment of the option price; and 
to make all other determinations and to take all other actions deemed 
necessary or advisable for the proper administration of the Plan.  All such 
actions and determinations shall be conclusively binding for all purposes and 
upon all persons.

     4. OPTIONS AUTHORIZED. The options granted under this Plan may be 
Incentive Stock Options or stock options that do not qualify as Incentive 
Stock Options (sometimes referred to herein as "nonqualified options" or 
"nonqualified stock options").  The Committee shall have the full power and 
authority to determine which options shall be nonqualified stock options and 
which shall be Incentive Stock Options; to grant only Incentive Stock Options 
or, alternatively, only nonqualified stock options; and to, in its sole 
discretion, grant to the holder of an outstanding option, in exchange for the 
surrender and cancellation of such option, a new option having a purchase 
price lower than that provided in the option so surrendered and cancelled and 
containing such other terms and conditions as the Committee may prescribe in 
accordance with the provisions of the Plan.  Under no circumstances may 
nonqualified stock options be granted where the exercise of such nonqualified 
stock options may affect the exercise of Incentive Stock Options granted 
pursuant to the Plan.  No options may be granted under the Plan prior to the 
Effective Date.  In addition to any other limitations set forth herein, (1) 
no Participant shall receive any grant of options, whether Incentive Stock 
Options or nonqualified stock options, exercisable for more than one hundred 
fifty thousand (150,000) shares of Common Stock during any one fiscal year of 
the Company and (2) the aggregate fair market value (determined in accordance 
with Paragraph 7(a) of the Plan as of the time the option is granted) of the 
stock with respect

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to which Incentive Stock Options are exercisable for the first time by a 
Participant in any calendar year (under all plans of the Company and of any 
Parent or Subsidiary) shall not exceed $100,000.

     5. COMMON STOCK SUBJECT TO OPTIONS. The aggregate number of shares of 
the Company's Common Stock which may be issued upon the exercise of options 
shall not exceed Three Million, Nine Hundred Sixty-Six Thousand, Six Hundred 
Sixty-Six (3,966,666), subject to adjustment under the provisions of 
Paragraph 8. The shares of Common Stock to be issued upon the exercise of 
options may be authorized but unissued shares, or shares issued and 
reacquired by the Company. In the event any option shall, for any reason, 
terminate or expire or be surrendered without having been exercised in full, 
the shares subject to such option shall again be available for options to be 
granted under the Plan, except that shares for which relinquished options (or 
portions thereof) are exercisable shall not again be available for options 
under the Plan.

     6. PARTICIPANTS. Except as hereinafter provided, options may be granted 
under the Plan to any Participant.  In determining the Participants to whom 
options shall be granted and the number of shares to be covered by such 
option, the Committee may take into account the nature of the services 
rendered by the respective Participants, their present and potential 
contributions to the Company's success and such other factors as the 
Committee in its discretion shall deem relevant.  A participant who has been 
granted an option under the Plan may be granted an additional option or 
options under the Plan, in the Committee's discretion.

     7. TERMS AND CONDITIONS OF OPTIONS. The grant of an option under the 
Plan shall be evidenced by a written agreement executed by the Company and 
the applicable Participant and shall contain such terms and be in such form 
as the Committee may from time to time approve, subject to the following 
limitations and conditions:

          (a)  OPTION PRICE.  The option price per share with respect to each
     option shall be determined by the Committee, but shall in no instance be
     less than the par value of the shares subject to the option.  In addition,
     the option price per share with respect to Incentive Stock Options granted
     hereunder shall in no instance be less than the fair market value of the
     shares subject to the option as determined by the Committee.  For the
     purposes of this Paragraph 7(a), fair market value shall be, where
     applicable, the closing price of the Common Stock on the Date of Grant as
     reported on the Vancouver Stock Exchange or other national securities
     exchange on which the Common Stock may be traded.  If the stock is not
     listed on a national securities exchange but is publicly traded on any
     securities exchange or in the over the counter market, the Committee shall
     determine the fair market value based on the closing prices or the bid and
     ask prices on any such exchange or market.  If the Common Stock was not
     traded on the Date of Grant, the nearest preceding date on which there was
     a trade shall be substituted.  Notwithstanding the foregoing, however, fair
     market value shall be determined consistent with Code Section 422A(b)(4) or

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     any successor provisions.  The Committee may permit the option purchase
     price to be payable by transfer to the Company of Common Stock owned by the
     option holder with a fair market value at the time of the exercise equal to
     the option purchase price.

          (b)  PERIOD OF OPTION.  The expiration date of each option shall be
     fixed by the Committee but, notwithstanding any provision of the Plan to
     the contrary, such expiration date shall not be more than ten (10) years
     from the Date of Grant.

          (c)  VESTING OF SHAREHOLDER RIGHTS.  Neither the optionee nor his
     successor in interest shall have any of the rights of a shareholder of the
     Company until the shares relating to the option hereunder are issued by the
     Company and are properly delivered to such optionee, or successor.

          (d)  EXERCISE OF OPTION.  Each option shall be exercisable from time
     to time (but not less than six (6) months after the Date of Grant) over
     such period and upon such terms and conditions as the Committee shall
     determine, but not at any time as to less than twenty-five (25) shares
     unless the remaining shares which have become so purchasable are less than
     twenty-five (25) shares.  After the death of the optionee, an option may be
     exercised as provided in Paragraph 15 hereof.

          (e)  NONTRANSFERABILITY OF OPTION.  No option shall be transferable or
     assignable by an optionee, other than by will or the laws of descent and
     distribution or pursuant to a qualified domestic relations order and each
     option shall be exercisable, during the optionee's lifetime, only by him or
     her or, during periods of legal disability, by his or her legal
     representative.  No option shall be subject to execution, attachment, or
     similar process.
                    
          (f)  DISQUALIFYING DISPOSITION.  The option agreement evidencing any
     Incentive Stock Options granted under this Plan shall provide that if the
     optionee makes a disposition, within the meaning of Section 425(c) of the
     Code and regulations promulgated thereunder, of any share or shares of
     Common Stock issued to him or her pursuant to exercise of the option within
     the two-year period commencing on the day after the Date of Grant of such
     option or within the one-year period commencing on the day after the date
     of issuance of the share or shares to him or her pursuant to the exercise
     of such option, he or she shall, within ten (10) days of such disposition
     date, notify the Company of the sales price or other value ascribed to or
     used to measure the disposition of the share or shares thereof and
     immediately deliver to the Company any amount of federal income tax
     withholding required by law.
                    
          (g)  LIMITATION ON GRANTS TO CERTAIN SHAREHOLDERS.  An incentive Stock
     Option may be granted to a Participant only if such Participant, at the
     time the option is granted, does not own, after application of the
     attribution rules of Code

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     Section 425, stock possessing more than 10% of the total combined voting 
     power of all classes of Common Stock of the Company or of its Parent or 
     Subsidiary.  The preceding restrictions shall not apply if at the time 
     the option is granted the option price is at least 110% of the fair 
     market value (as defined in Paragraph 7(a) above) of the Common Stock 
     subject to the option and such option by its terms is not exercisable 
     after the expiration of five (5) years from the Date of Grant.
                    
          (h)  CONSISTENCY WITH CODE.  Notwithstanding any other provision in
     this Plan to the contrary, the provisions of all agreements granting
     incentive stock options pursuant to the Plan shall not violate the
     requirements of the Code applicable to the Incentive Stock Options
     authorized hereunder.

     8. ADJUSTMENTS. The Committee, in its discretion, may make such 
adjustments in the option price and the number of shares covered by 
outstanding options that are required to prevent any dilution or enlargement 
of the rights of the holders of such options that would otherwise result from 
any reorganization, recapitalization, stock split, stock dividend, 
combination of shares, merger, consolidation, issuance of rights or any other 
change in the capital structure of the Company.  The Committee, in its 
discretion, may also make such adjustments in the aggregate number of shares 
that may be the subject of options which are appropriate to reflect any 
transaction or event described in the preceding sentence.

     9. RESTRICTION OF ISSUING SHARES. The exercise of each option shall be 
subject to the condition that if at any time the Company shall determine in 
its discretion that the satisfaction of withholding tax or other withholding 
liabilities, or that the listing, registration, or qualification of any 
shares otherwise deliverable upon such exercise upon any securities exchange 
or under any state or federal law, or that the consent or approval of any 
regulatory body, is necessary or desirable as a condition of, or in 
connection with, such exercise or the delivery or purchase of shares pursuant 
thereto, then in any such event, such exercise shall not be effective unless 
such withholding, listing, registration, qualification, consent, or approval 
shall have been effected or obtained free of any conditions not acceptable to 
the Company.

     10. USE OF PROCEEDS. The proceeds received by the Company from the sale 
of Common Stock pursuant to the exercise of options granted under the Plan 
shall be added to the Company's general funds and used for general corporate 
purposes.

     11. AMENDMENT, SUSPENSION, AND TERMINATION OF PLAN. The Board may at any 
time suspend or terminate the Plan or may amend it from time to time in such 
respects as the Board may deem advisable in order that the options granted 
thereunder may conform to any changes in the law or in any other respect that 
the Board may deem to be in the best interests of the Company; provided, 
however, that without approval by the shareholders of the Company voting the 
proper percentage of its voting power, no such amendment shall make any 
change in the Plan for which shareholder approval is required of the Company 
in order to comply with (i) Rule 16b-3, as amended,

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promulgated under the Exchange Act, (ii) the Code or regulatory provisions 
dealing with Incentive Stock Options, (iii) any rules for listed companies 
promulgated by any national stock exchange on which the Company's stock is 
traded or (iv) any other applicable rule or law. Unless sooner terminated 
hereunder, the Plan shall terminate ten (10) years after the Effective Date.  
No option may be granted during any suspension or after the termination of 
the Plan.  Except as provided in Paragraph 12, no amendment, suspension, or 
termination of the Plan shall, without an optionee's consent, impair or 
negate any of the rights or obligations under any option theretofore granted 
to such optionee under the Plan.

     12. TAX WITHHOLDING. The Committee may, in its sole discretion, (a) 
require an optionee to remit to the Company a cash amount sufficient to 
satisfy, in whole or in part, any federal, state or local withholding tax 
requirements prior to the delivery of any certificate for shares pursuant to 
the exercise of an option hereunder; or (b) satisfy such withholding 
requirements through another lawful method.

     13. EFFECTIVE DATE OF PLAN. This Plan shall become effective on the date 
(the "Effective Date") of the last to occur of (i) the adoption of the Plan 
by the Board and (ii) the approval, within twelve (12) months of such 
adoption, by a majority (or such other proportion as may be required by state 
law) of the outstanding voting shares of the Company, voted either in person 
or by proxy, at a duly held stockholders meeting.

     14. TERMINATION OF EMPLOYMENT. In the event of the retirement (with the 
written consent of the Company) or other termination of the employment of an 
employee to whom an option has been granted under the Plan, other than (a) a 
termination that is either (i) for cause or (ii) voluntary on the part of the 
employee and without the written consent of the Company, or (b) a termination 
by reason of death, the employee may (unless otherwise provided in his option 
agreement) exercise his option at any time within three (3) months after such 
retirement or other termination of employment (or within one (1) year after 
termination of employment due to disability within the meaning of Code 
Section 422A(c)(7)), or within such other time as the Committee shall 
authorize, but in no event after ten (10) years from the date of granting 
thereof (or such lesser period as may be specified in the stock option 
agreement), but only to the extent of the number of shares for which his 
options were exercisable by him at the date of the termination of his 
employment.  In the event of the termination of the employment of an employee 
to whom an option has been granted under the Plan that is either (i) for 
cause or (ii) voluntary on the part of the employee and without the written 
consent of the Company, any option held by him under the Plan, to the extent 
not previously exercised, shall forthwith terminate on the date of such 
termination of employment.  Options granted under the Plan shall not be 
affected by any change of employment so long as the holder continues to be an 
employee of the Company, a Subsidiary or a Parent.  The option agreement may 
contain such provisions as the Committee shall approve with respect to the 
effect of approved leaves of absence.  Nothing in the Plan or in any option 
granted pursuant to the Plan shall confer on any individual any right to 
continue in the employ of the Company or any of its Subsidiaries or Parents 
or interfere in any way with the right of the Company or any of its 

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Subsidiaries or Parents to terminate his employment at any time.

     15. DEATH OF HOLDER OF OPTION. In the event an employee to whom an 
option has been granted under the Plan dies during, or within three (3) 
months after the termination of, his employment by the Company or a 
Subsidiary or Parent, such option (unless it shall have been previously 
terminated pursuant to the provisions of the Plan or unless otherwise 
provided in his option agreement) may be exercised (to the extent of the 
entire number of shares covered by the option whether or not purchasable by 
the employee at the date of his death) by the executor or administrator of 
the optionee's estate or by the person or persons to whom the optionee shall 
have transferred such option by will or by the laws of descent and 
distribution, at any time within a period of one (1) year after his death, 
but not after the exercise termination date set forth in the relevant stock 
option agreement.

     16. LOANS TO ASSIST IN EXERCISE OF OPTIONS. If approved by the Board, 
the Company or any Parent or Subsidiary may lend money or guarantee loans by 
third parties to an individual to finance the exercise of any option granted 
under the Plan to carry Common Stock thereby acquired.  No such loans to 
finance the exercise of an Incentive Stock Option shall have an interest rate 
or other terms that would cause any part of the principal amount to be 
characterized as interest for purposes of the Code.

     17. RULE 16b-3 PLAN. This Plan is intended and has been drafted to 
comply in all respects with Rule 16b-3, as amended, under the Exchange Act.  
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.