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                                                                   Exhibit 10.27

                                  Offer Letter

February 20, 2002




Glenn Wienkoop
21178 Maria Lane
Saratoga, CA  95070

Dear Glenn:

It gives me great pleasure to offer you the position of President and Chief
Operating Officer for Portal Software, Inc. (Portal) reporting to me. This offer
is valid for five (5) business days. We plan for you to begin employment with us
as soon as possible, the precise start date to be agreed upon. Your compensation
and employee benefits package will include the following:

Starting Salary

You will receive a semi-monthly salary of fourteen thousand, five hundred
eighty-three dollars and thirty-four cents ($14,583.34).

Incentive Plan

You are eligible to receive an 80% bonus payment annually, based on company
financial performance against financial objectives established by the Board of
Directors.

Benefits

You will participate in the standard Portal benefit plan, including normal
Portal holidays.

Stock Options

Subject to the approval of the Board of Directors, you will be granted an option
to purchase one million (1,000,000) shares of Portal common stock. The exercise
price will be the fair market value on the date the options are granted by the
Board of Directors after your date of hire. The option vests over a four (4)
year period from your start of employment (25% after one year and the balance in
equal monthly installments over the last three years).

Relocation

In terms of relocation we will reimburse you all reasonable and customary
relocation expenses on your relocation from Cincinnati to Cupertino including:
closing costs on the sale of your Cincinnati home, automobile shipment,
household goods, and travel expenses for you between Cupertino and Cincinnati
until the end of April 2002, and thereafter subject to review and extension.

<PAGE>

Glenn Wienkoop
Page 2
February 20, 2002




Termination

Should your employment with the Portal terminate by reason of an Involuntary
Termination then you will become entitled to receive the following severance
benefits, provided you promptly execute and deliver to Portal a general release
of claims in form and substance reasonably satisfactory to Portal: one year's
base salary and target bonus. The severance shall be paid to you biweekly over
the course of 12 months in accordance with Portal's normal payroll practices and
subject to all applicable withholding taxes.
"Target Bonus means the target bonus (as a percentage of base salary) in effect
for you under your cash incentive bonus program in effect for you at the time of
your termination. "Involuntary Termination" means any involuntary termination by
Portal of your employment with Portal other than as a result of death,
Disability or Termination for Cause. "Disability" means your inability to
perform the normal and usual duties of your position with Portal by reason of
any physical or medical impairment that is expected to result in death or
continue for a period of twelve (12) consecutive months or more. "Termination
for Cause" means Portal's termination of your employment for any of the
following reasons: (I) your commission of any act of fraud, embezzlement or
dishonesty, (ii) your unauthorized use or disclosure of any confidential
information or trade secrets of Portal, (iii) any intentional misconduct by you
which has an adverse effect upon Portal's business or reputation, (iv) your
continued failure to perform the major duties, functions and responsibilities of
your position after written notice from Portal identifying the deficiencies in
your performance and a reasonable cure period of not less than thirty (30) days
or (v) a material breach of your fiduciary duties as an officer of Portal.

Change in Control

Upon the commencement of your employment, Portal would enter into with you the
standard form of change in control agreement for Section 16 reporting officers.
A copy of the agreement is attached hereto.

While Portal's goal is an ongoing, mutually rewarding employment relationship
with every employee, Portal does not enter into employment agreements for fixed
terms. Employment with Portal is at-will, which means that both the employee and
Portal retain the right to terminate the employment relationship at any time,
with or without cause. This is the full and complete agreement between us on
this term. Although your job duties, title, compensation and benefits, as well
as Portal's personnel policies and procedures, may change from time-to-time, the
"at will" nature of your employment may only be changed in a document signed by
you and the President of Portal.

Please note that, in compliance with the Immigration Reform Act of 1986, all new
employees are required to submit proof of U.S. citizenship or legal alien status
within three business days of employment with Portal. Enclosed is an I-9 Form
that lists the documents that you can present to fulfill this requirement.
Please bring your documents, along with a completed I-9 Form, on your first day
of employment.

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Glenn Wienkoop
Page 3
February 20, 2002




Your employment with Portal is contingent upon the accuracy of the information
you have provided, as well as a completed background investigation and reference
checks. In consideration of your employment, you agree to conform to the rules
and regulations of Portal. This offer and your employment are contingent upon
receipt of your signature on our standard Proprietary Information and Inventions
Agreement, which are enclosed and upon approval of these terms by the Board of
Directors or a committee of the Board. Upon acceptance of this offer, please
sign and have your signature witnessed on the Proprietary Information and
Inventions Agreement, sign the original offer letter, and return all documents
to Margaret Kane in Human Resources in the Cupertino, CA office. A copy of the
offer letter is enclosed for your files.

Glenn, I am sure you will find Portal an exciting and challenging environment in
which to work and I look forward to your becoming a part of our team.

Sincerely,                           Offer Accepted:
                                                    ----------------------------

                                     Date:
                                          --------------------------------------


John E. Little
Chief Executive Officer              Start Date:     02/20/2002
                                                --------------------------------

JEL/mk
Enclosures