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                                                                   EXHIBIT 10(b)



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                         OVERNITE TRANSPORTATION COMPANY

                          EMPLOYEE STOCK PURCHASE PLAN














                 (As Amended Effective as of November 19, 1998)



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                         OVERNITE TRANSPORTATION COMPANY
                          EMPLOYEE STOCK PURCHASE PLAN


                                   I. Purpose

         The purpose of the Overnite Transportation Company Employee Stock
Purchase Plan (the "Plan") is to promote employee ownership in Union Pacific
Corporation ("Union Pacific"), the indirect parent company of Overnite
Transportation Company (the "Company"). The Company has demonstrated by the
results of prior annual offerings to its employees of its own stock, before it
became an indirect wholly-owned subsidiary of Union Pacific, that it is greatly
beneficial to have as many stockholder employees as possible. The high morale
and goodwill generated by such stock offerings have been deemed major
contributing factors to the operating efficiency and profitability of the
Company. The Company wishes to continue this practice by selling shares of Union
Pacific common stock (the "Stock") to the Company's employees.

                               II. Administration

         The Plan is administered by the Company's Board of Directors (the
"Board"), whose members are elected by the Company's shareholder(s) and,
indirectly, by Union Pacific. The Board has the authority to make rules and
regulations for carrying out the Plan as it may deem advisable.

         The number of shares which may be issued under the Plan from time to
time is limited to 2,000,000 shares. The Board will determine the aggregate
amount of Stock available for employees' subscriptions in any single year. For
1988, employees may subscribe for an aggregate of up to 150,000 shares of Stock.
The Board may choose, in its discretion, whether or not to make shares of Stock
available for subscription under the Plan in any subsequent year.



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         Interpretation and construction of any provision of the Plan by the
Board are final and conclusive. The Board reserves the right to amend the Plan
or terminate the Plan. The Board does not receive any compensation from the
Plan. All requests concerning the Plan should be directed to the Plan
Administrator, Chief Financial Officer, Overnite Transportation Company, 1000
Semmes Avenue, Richmond, Virginia 23224, telephone number (804) 231-8000.

                                III. Eligibility

         All employees of the Company and any Subsidiary of the Company, on the
Subscription Date shall be eligible to participate in the Plan.

                                 IV. Definitions

A.       Subscription Date

         The Subscription Date shall be the last date available each year to
         subscribe to the Plan, as determined by the Board.

B.       Exercise Date

         The Exercise Date shall be the last date on which an employee may
         cancel his subscription and withdraw from the Plan, as determined by
         the Board, provided that the Exercise Date shall not be more than
         twelve (12) months after the date on which the Board authorizes the
         related sale of Stock pursuant to the Plan.

C.       Issue Date

         The Issue Date shall be the date each year on which the shares sold
         under the Plan are distributed to the subscribers, as determined by the
         Board.

D.       Stock

         The Stock is traded on the New York Stock Exchange.





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E.       Subscription Price

         The Subscription Price of the Stock shall be ninety-five percent (95%)
         of the closing price of the Stock on the date which is seven (7)
         business days prior to the date of the Prospectus, rounded to the
         nearest dollar (the "Preliminary Subscription Price"), but not less
         than eighty-five percent (85%) of the Fair Market Value of the Stock on
         the Subscription Date.

F.       Exercise Price

         The Exercise Price of the Stock shall be ninety-five percent (95%) of
         the closing price of the Stock on the Exercise Date, rounded to the
         nearest dollar, but not less than eighty-five percent (85%) of the Fair
         Market Value of the Stock on such date.

G.       Option Price

         The Option Price of the Stock shall be the lesser of the Subscription
         Price or the Exercise Price.

H.       Subsidiary

         The term Subsidiary shall mean any corporation in which the Company
         owns at least 50% of the voting power of all classes of stock combined.

I.       Fair Market Value

         The Fair Market Value of the Stock on any particular date shall mean
         the average of the high and low trading prices of the Stock on such
         date, as reported in The Wall Street Journal listing of consolidated
         trading for New York Stock Exchange Issues for such date.





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                                V. General Terms

         Each employee may subscribe annually for up to 200 shares but not less
than 5 shares of stock. All subscriptions must be in multiples of 5 shares. If
the Subscription Price is determined to be eighty-five percent (85%) of the Fair
Market Value of the Stock on the Subscription Date and this price exceeds the
Preliminary Subscription Price by such dollar amount as determined by the Board,
each employee shall have the right to reduce, in multiples of 5 shares, the
number of shares to which he previously subscribed. The right to purchase such
Stock is nontransferable.

         The total number of shares available for the Plan will be determined
annually by the Board. In the event of oversubscription, the Board will prorate
the shares being sold on the basis of the number of shares which continue to be
subscribed to as of the close of the Exercise Date, provided that each
subscriber receives at least five shares.

         No employee may subscribe to any Stock if he, and anyone whose Stock is
attributed to him, would, when considered together, thereby owns 5% of more of
the outstanding Stock. No employee may purchase under the Plan or any other
employee stock purchase plan under Section 423 of the Internal Revenue Code of
1986, as amended (the "Code"), maintained by an parent or subsidiary corporation
of the Company, as such terms are defined in Section 424 of the Code, more than
$25,000 of Stock in any year.

         All shares purchased under the Plan will be sold on the Issue Date
after payment in full of the Option Price. An employee may pay cash with his
subscription for the whole or any portion of the cost of his subscription based
on the Subscription Price or he may use the Payroll Deduction Plan for the whole
cost or any deferred portion thereof. Should the Exercise Price be





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lower than the Subscription Price, then the Company will refund all excess funds
paid by the employee.

         At any time on or before the Exercise Date, any employee may cancel his
subscription and receive from the Company the funds that he deposited. Except
for a reduction as described above, no partial withdrawal of a subscription will
be permitted.

         If any subscriber ceases to be an employee of the Company before the
Exercise Date, except by death or retirement, his subscription will be
automatically cancelled. All funds deposited will be returned. Such cancellation
shall not be affected by any subsequent re-employment. An employee shall not
assign or hypothecate his interest in the Plan.

         Upon the death of any subscribing employee, his executor or
administrator may elect to pay the entire unpaid balance of the subscription in
cash before the Exercise Date, in order to continue the employee's subscription
for Stock. If any subscriber retires (normal, early, disability or delayed), and
elects to retain his subscription, he may do so by paying the remaining balance
in cash before the Exercise Date.

                           VI. How Employee Subscribes

         Any employee may subscribe for Stock by returning to the Company, on or
before the Subscription Date, an executed Subscription Agreement supplied by the
Company.

                           VII. Payroll Deduction Plan

         The Payroll Deduction Plan provides for deductions from the employee's
pay at the rate of one-fortieth (1/40) of the whole or deferred portion of the
Subscription Price of the Stock subscribed to for forty (40) successive weeks.
Status reports will be furnished to the employee upon written request.



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                                 VIII. Interest

         Each month, the Company will credit the employee's account with
interest at the rate of 5-3/4% per annum computed on all funds held under the
Plan. All earned interest will be paid directly to the employee upon
distribution of the Stock or cancellation of the entire subscription.

                       IX. Stock Dividends or Stock Splits

         In the event of a Stock dividend or Stock split with a record date
prior to the Issue Date, an appropriate adjustment will be made in the number of
shares to be delivered under the Plan.

                                    X. Costs

         Participants in the Plan shall not pay any brokerage commissions,
service charges or other fees for purchases made under the Plan. All costs of
administration of the Plan shall be paid by the Company.