<PAGE>

                                                                   EXHIBIT 10.26

                                                             [LOGO APPEARS HERE]

August 28, 2001  Revised

Kevin Kennedy
690 Loyola Drive
Los Altos, CA 94124

Dear Kevin:

I am delighted to make you this offer to join Openwave Systems Inc. effective
August 22, 2001.  This offer letter serves to confirm our previous discussions.

The offer is for you to join us as Chief Operating Officer, reporting to me.
Your responsibilities will include: Product Development, Marketing, IT, Business
Development, Market Development, Corporate Development, including mergers and
acquisitions, and Office of Customer Operations {OCO Sales & Customer Advocacy}.

 .  Your monthly salary will be $31,250 per month, or $375,000.00 on an
   annualized basis.

 .  You are eligible to participate in the Corporate Bonus Program with a target
   of 75% of your annual salary. Your actual payout for the 2001 plan year will
   be based on your actual base salary earned during 2001. Corporate performance
   determines the payout pool, while your individual performance determines your
   actual payout. The program is subject to specific terms and conditions, which
   will be provided under separate cover. During your first 12 months of
   employment only, Openwave will guarantee corporate performance at target
   level.

 .  Providing you are employed as a regular full time employee by Openwave
   Systems Inc. (or one of its subsidiaries) on the following dates, and based
   upon the completion of mutually agreed upon initial deliverables, Openwave
   will pay you the gross cash bonus corresponding with each respective date
   listed below:

          September 1, 2001      $250,000
          November 1, 2001       $250,000
          January 1, 2002        $250,000

     Should your employment with Openwave voluntarily terminate within your
     first twelve (12) months of employment, you agree to pay back the bonuses
     on a pro-rated basis, with pro-ration based upon the number of months of
     your service with the Company.

 .  Subject to the approval of the Compensation Committee of the Board of
   Directors of Openwave you will be granted options to purchase 2,500,000
   shares of Common Stock. This will be broken into three separate grants; the
   first grant of 2,000,000 shares will be made within two(2) weeks of your
   start date and subsequent grants for 250,000 shares each, will be granted in
   February, 2002 and August, 2002, respectively, on dates determined by the
   Compensation Committee at an exercise price equal to the closing price of the
   Common Stock on the respective grant dates. The vesting commencement date and
   the date of grant will be the same. The shares will vest over four years with
   a one year cliff, meaning that one fourth of your shares will be vested one
   year from your vesting commencement date and the remaining shares will vest
   monthly thereafter. Vesting will, of course, depend on your continued
   employment with Openwave.

 .  Providing you are employed as a regular full time employee by Openwave
   Systems Inc. (or one of its subsidiaries) on the following dates, and based
   upon the completion of mutually agreed upon deliverables, Openwave will pay
   you the net cash bonus (bonus will be grossed up for taxes) corresponding
   with each respective date listed below:

          June 30, 2002           $235,000
          September 30, 2002      $210,000
          December 31, 2002       $206,000
          March 31, 2003          $205,000
          June 30, 2003           $203,000
          August 31, 2003         $200,000

<PAGE>

                                                             [LOGO APPEARS HERE]

 .  Subject to the approval of the Compensation Committee of the Board of
   Directors of Openwave, you will be granted, as of your date of employment,
   150,000 shares of restricted stock. The shares will vest as follows: 25,000
   shares will be immediately vested upon date of grant, and 25,000 shares will
   vest at the end of each calendar quarter beginning 12/31/01, with 100%
   vesting on 12/31/02. Vesting will, of course, depend on your continued
   employment with Openwave.

 .  Openwave will provide you with a loan of $1,200,000 which you may use to
   assist in the payment of taxes on the grant of restricted stock, should you
   decide to file an 83(b) election. Details and terms of the loan will be
   provided in the loan document.

 .  As an employee, you are also eligible to receive our standard employee
   benefits.

 .  You should be aware that your employment with Openwave is for no specified
   period and constitutes "at will" employment. As a result, you are free to
   resign at any time, for any reason or for no reason. Similarly, Openwave is
   free to conclude its employment relationship with you at any time, with or
   without cause. Should your employment be terminated except "for cause" during
   the first 24 months of employment, you will be eligible to receive a
   severance package equal to 12 months of target pay and benefits, excluding
   the further vesting of option. After 24 months of employment, this severance
   package will be equal to six months of target pay and benefits, excluding the
   further vesting of options.

          "Cause" shall mean (i) gross negligence or willful misconduct in the
          performance of the Employee's duties to the Company; (ii) repeated
          unexplained or unjustified absence from the Company; (iii) a material
          and willful violation of any federal or state law; (iv) refusal or
          failure to act in accordance with any specific direction or order of
          the Company; (v) commission of any act of fraud with respect to the
          Company; or (vi) conviction of a felony or a crime involving moral
          turpitude causing material harm to the standing and reputation of the
          Company, in each case as determined by the Board of Directors of the
          Company.

   You will be offered to sign a change of control agreement that provides for
   75% accelerated vesting of stock and stock options upon a change of control
   and the remaining 25% vested if your employment is deemed involuntarily
   terminated as a result of a substantial diminishment of responsibilities
   within a 12-month period after the Company is acquired. In addition, under
   these circumstances, and upon your termination the outstanding balance on any
   loans extended to you by Openwave will also be forgiven and "grossed up" for
   any taxes then due on income resulting from forgiveness of the indebtedness.
   More details will be provided in the change of control agreement, which will
   be provided under separate cover.

   You are invited to attend Day One Orientation on your first day of work
   during which you will learn more about Openwave's business, culture and
   benefits. Our Human Resources Department will contact you regarding the
   specific details for your orientation. For purposes of Federal Immigration
   Law, you will be required to provide to the Company documentary evidence of
   your identity and eligibility for employment in the United States. Such
   documentation must be provided to us within three (3) business days of your
   date of hire, or our employment relationship with you may be terminated.

   Upon joining Openwave you will be required to sign confidentiality and
   invention agreement in which you will be asked to protect the company's
   confidential information and to assign to the company any inventions produced
   in the course of your work.
<PAGE>

                                                             [LOGO APPEARS HERE]

     Please review these terms to make sure they are consistent with your
     understanding.  If so, please sign and return this offer letter via fax to
     Alicia Villegas at 650 480-7414.

     Your acceptance of this offer represents a unique opportunity for Openwave
     both to grow and to succeed. I want to thank you for the commitment you
     have made to our common vision and look forward to working with you.

                                                 Accepted by:

           ---------------------------           -----------------------------
           Don Listwin                           Kevin Kennedy
           President and CEO