Exhibit 10.1

June 15, 2007

Bernard J. Cassidy

700 Saginaw Drive

Redwood City, CA 94063

Dear Barney,

I am pleased to confirm that the Board of Directors has approved the amendment
of your employment arrangement as follows.

Salary and Bonus. Your base salary will be $9,583.34 per semi-monthly pay
period, which is equivalent to $230,000.00 on an annualized basis, effective
retroactively to January 1, 2007. In addition, you will be eligible for an
annual incentive bonus program which at target allows you to earn bonuses equal
to 76.5% of your annual salary.

Change of Ownership Control. If a Change of Ownership Control occurs during your
tenure as Senior Vice President and General Counsel, followed within six months
by either (i) the termination of your employment by the successor to Tumbleweed
for any reason other than Cause or (ii) Constructive Termination, then, subject
to your delivery of a signed release of claims in a form reasonably satisfactory
to such successor, (i) immediately prior to such termination or Constructive
Termination the vesting of one hundred percent of your then-outstanding stock
options shall occur, (ii) you will be entitled to receive continuation of your
base salary for a period of nine months, paid in accordance with Tumbleweed’s
payroll practices and subject to normal tax withholdings, and (iii) you will be
entitled to reimbursement of the costs of COBRA coverage for you and any covered
dependants for a period of nine months following such termination.

Death or Disability. In the event of the termination of your employment with
Tumbleweed as a result of your death or Disability, subject to the delivery by
you or your estate of a signed release of claims in a form reasonably
satisfactory to Tumbleweed, you will be entitled to continuation for a period of
six months of base salary and, as determined by Tumbleweed, either
(i) continuation for a period of six months of the vesting of your
then-outstanding Tumbleweed stock options or (ii) six months’s acceleration of
the vesting of your then-outstanding Tumbleweed stock options.

Other Termination. In circumstances other than the Change of Ownership Control,
death, or Disability scenarios, each as described above, if (a) Tumbleweed
terminates your employment for any reason other than Cause, or (b) you terminate
your employment following a Constructive Termination, then, subject to your
delivery of a signed release of claims in a form reasonably satisfactory to
Tumbleweed, you will be entitled to (i) continuation for a period of nine months
of your base salary, paid in accordance with Tumbleweed’s payroll practices,
(ii) continuation for a period of nine months of the vesting of your
then-outstanding Tumbleweed stock options, and (iii) continuation of your health
benefits for nine months.

In the event of termination for Cause, you will not be entitled to any such
payments, salary, bonus, or benefits.

Certain Definitions. For purposes of this agreement,

 

  •  

“Cause” means only: the commission of a felony by you intended to result in your
substantial personal enrichment at Tumbleweed’s expense, conviction of a crime
involving moral turpitude, or willful failure to perform your duties to
Tumbleweed, which failure is deliberate, results in injury to Tumbleweed, and
continues for more than 15 days after written notice is given to you. For
purposes of this definition, no act or omission is considered to have been
“willful” unless it was not in good faith and you had knowledge at the time that
the act or omission was not in the best interests of Tumbleweed.

 

  •  

“Change of Ownership Control” means any sale of all or substantially all of
Tumbleweed’s assets, or any merger, consolidation, or stock sales that results
in the holders of Tumbleweed’s capital stock immediately prior to such
transaction owning less than 50% of the voting power of Tumbleweed’s capital
stock immediately after such transaction.

 

  •  

“Constructive Termination” means a material diminution of duties, a change in
title or reporting relationship, a change greater than 25 miles in the location
of your designated work place for Tumbleweed, a reduction in base salary, or the
failure of any successor to the assets or business through any Change of
Ownership Control to fully assume all obligations of Tumbleweed under this
agreement.

 

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  •  

“Disability” means an illness, injury or other incapacitating condition as a
result of which you are unable to perform your duties at Tumbleweed for any six
(6) consecutive months. In any such event, Tumbleweed, in its sole discretion,
may terminate your employment by giving you notice of termination for
Disability. You agree to submit to such medical examinations as may be necessary
to determine whether a Disability exists, pursuant to such reasonable requests
made by Tumbleweed from time to time, and any determination as to the existence
of a Disability shall be made by a physician selected by Tumbleweed.

Other Agreements. As a condition of receipt of the aforementioned payments and
other benefits, you will be required to comply with the terms of the Proprietary
Information and Inventions Agreement between you and Tumbleweed dated May 24,
1999 (the “PIIA”), the various agreements related to your Tumbleweed stock
options (the “Stock Option Agreements”), the Tumbleweed Communications Employee
Manual and other policy documents applicable to Tumbleweed employees, and any
plan documents (the “Plan Documents”) governing Tumbleweed health benefits
insurance programs, retirement plans and all other benefit programs and
arrangements. The terms and conditions in the Employee Manual and the Plan
Documents are subject to change at any time by Tumbleweed, subject to
requirements of federal, state or local law.

This Agreement, together with the PIIA, the Stock Option Agreements, the
Tumbleweed Communications Employee Manual and other policy documents applicable
to Tumbleweed employees, and the Plan Documents, contain all the understandings
between you and Tumbleweed with respect to your employment with Tumbleweed or
the termination thereof, and supercede all other prior agreements and
understandings, whether oral or in writing, including but not limited to the
letter agreements between you and Tumbleweed dated May 19, 1999, July 20, 2001,
and June 29, 2006.

At-Will Employment. Your employment continues to be voluntarily entered into and
is for no specific period. As a result, you are free to resign at any time, for
any reason, or for no reason. Similarly, Tumbleweed is free to conclude its
at-will employment relationship with you at any time, with or without cause.

 

/s/ James P. Scullion       James P. Scullion, CEO            

Please indicate acceptance of this offer by returning this document with your
signature.

 

I agree to and accept the enclosed offer.

/s/ Bernard J. Cassidy    June 15, 2007    Bernard J. Cassidy    Date   

 

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