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                                                                  EXHIBIT 10.1.8


                                    ADDENDUM
                                       TO
                            STOCK ISSUANCE AGREEMENT

         The following provisions are hereby incorporated into, and are hereby
made a part of, that certain Stock Issuance Agreement (the "Issuance Agreement")
by and between BPO-US, Inc. (the "Corporation") and _________________
("Participant") evidencing the shares of Common Stock purchased on this date by
Participant under the Corporation's 1999 Stock Option/Stock Issuance Plan, and
such provisions shall be effective immediately. All capitalized terms in this
Addendum, to the extent not otherwise defined herein, shall have the meanings
assigned to such terms in the Issuance Agreement.

                        INVOLUNTARY TERMINATION FOLLOWING
                              CORPORATE TRANSACTION

         1. To the extent the Repurchase Right is assigned to the successor
corporation (or parent thereof) in connection with a Corporate Transaction, no
accelerated vesting of the Purchased Shares shall occur upon such Corporate
Transaction, and the Repurchase Right shall continue to remain in full force and
effect in accordance with the provisions of the Issuance Agreement. Participant
shall, over his or her period of Service following the Corporate Transaction,
continue to vest in the Purchased Shares in one or more installments in
accordance with the provisions of the Issuance Agreement. However, upon an
Involuntary Termination of Participant's Service within eighteen (18) months
following the Corporate Transaction, the Repurchase Right shall terminate
automatically, and all the Purchased Shares shall immediately vest in full at
that time.

         2. For purposes of this Addendum, the following definitions shall be in
effect:

         An INVOLUNTARY TERMINATION shall mean the termination of Participant's
Service by reason of:

            (a) Participant's involuntary dismissal or discharge by the
         Corporation for reasons other than for Misconduct, or

            (b) Participant's voluntary resignation following (A) a change in
         his or her position with the Corporation (or Parent or Subsidiary
         employing Participant) which materially reduces his or her duties and
         responsibilities or the level of management to which he or she reports,
         (B) a reduction in Participant's level of compensation (including base
         salary, fringe benefits and target bonuses under any
         corporate-performance based incentive programs) by more than fifteen
         percent (15%) or (C) a relocation of Participant's place of employment
         by more

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         than fifty (50) miles, provided and only if such change, reduction or
         relocation is effected by the Corporation without Participant's
         consent.

         MISCONDUCT shall include the termination of Participant's Service by
reason or Participant's commission of any act of fraud, embezzlement or
dishonesty, any unauthorized use or disclosure by Participant of confidential
information or trade secrets of the Corporation (or any Parent or Subsidiary),
or any other intentional misconduct by Participant adversely affecting the
business or affairs of the Corporation (or any Parent or Subsidiary) in a
material manner. The foregoing definition shall not be deemed to be inclusive of
all the acts or omissions which the Corporation (or any Parent or Subsidiary)
may consider as grounds for the dismissal or discharge of the Participant or any
other individual in the Service of the Corporation (or any Parent or
Subsidiary).

         IN WITNESS WHEREOF, BPO-US, Inc. has caused this Addendum to be
executed by its duly-authorized officer as of the Effective Date specified
below.


                                             BPO-US, INC.

                                             By:
                                                --------------------------------

                                             Title:
                                                    ----------------------------


EFFECTIVE DATE:                  , 199
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