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                                                                    EXHIBIT 10.5


                                 PEERLOGIC, INC.

             FEBRUARY 2000 INCENTIVE PLAN - UNITED KINGDOM SUB-PLAN

The Board of Directors of PeerLogic, Inc., a California corporation (the
"COMPANY") has established these rules (the "UK RULES") for purposes of
operating the February 2000 Incentive Plan of the Company (the "PLAN") in a
manner which complies with UK law and practice in relation to grants of stock
options to Participants in the United Kingdom of options for the acquisition of
Common Stock.

The options (the "OPTIONS") to which the UK Rules apply are those to which the
UK Rules are expressed to apply at the time when the Options are granted. The
Plan, as supplemented or modified by the UK Rules, is referred to as the
"SUB-PLAN". Unless the context otherwise requires, expressions used in the UK
Rules have the same meanings as in the Plan and expressions not defined in the
Plan have the meanings given to them by this Sub-Plan.

The Plan annexed hereto shall apply as if incorporated into this Sub-Plan with
the following modifications which override any inconsistent provisions of the
Plan:

1.   An Option shall only be transferable or assignable by the Optionee by will
     or the laws of intestacy. During the Optionee's lifetime, only an Optionee
     may exercise an Option.

2.   No grants of Incentive Stock Options will be made under the Sub-Plan.

3.   The amount due on the exercise of an Option will be paid only in cash or by
     cheque and the Optionee will bear all currency risks and costs associated
     with exercising an Option.

4.   An Option shall not afford the Optionee any rights or additional rights to
     compensation or damage as a consequence of the loss or termination of
     office or employment with any Group Company (defined below) for any reason
     whatsoever (including, without limitation, wrongful or unfair dismissal).
     Any loss or potential loss which an Optionee may suffer by reason of being
     unable to exercise an Option or the loss of any other right or benefit or
     prospective right or benefit under the Plan resulting from the loss or
     termination of the Optionee's office or employment with any Group Company
     shall not afford the Optionee any rights or additional rights to
     compensation or damage.

5.   No Option shall be exercisable and no obligation shall arise upon the
     Company to procure the issue of or purchase of Common Stock or transfer
     Common Shares or do any other thing in relation to an Option and/or do any
     other thing in relation to an Optionee under or in connection with the Plan
     (together "Grantor Action") unless and until the Company is satisfied in
     its absolute discretion that either:

     5.1. Such person has made payment, or has made arrangements satisfactory to
          the Company for the payment to it and/or to any Subsidiary, of such
          sum as is, in the sole discretion of the Company, sufficient to
          satisfy any liability for any tax and/or (to the extent lawful from
          time to time) national insurance contributions or the like in any
          jurisdiction which are or would be recoverable from such person as a
          result of such Grantor Action or the exercise of an Option and in
          respect of which the Company and/or any Subsidiary is liable to
          account (in any jurisdiction); or

     5.2. Such person has entered into an agreement with it and/or any
          Subsidiary (in a form satisfactory to the Company) to ensure that such
          payment is made by the Optionee.

6.   In this Sub-Plan, "GROUP COMPANY" means the Company and its subsidiaries
     from time to time or any company which is its Holding Company or Subsidiary
     of such holding company from time to time (where "Holding Company" and
     "Subsidiary" have the same meanings given to them by the UK Companies Act
     1985).