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                                                                   EXHIBIT 10.56

                              AMENDED AND RESTATED
                     EXECUTIVE SEVERANCE BENEFITS AGREEMENT

     This Amended and Restated Executive Severance Benefits Agreement (the
"Agreement") is entered into this 31/st/ day of December, 2002 (the "Effective
Date"), between Brent K. Blackburn ("Executive") and CV Therapeutics, Inc. (the
"Company"). This Agreement is intended to provide Executive with the
compensation and benefits described herein upon the occurrence of specific
events. Certain capitalized terms used in this Agreement are defined in Article
6.

     The Company and Executive hereby agree as follows:

                                    ARTICLE 1

                  Scope of and Consideration for this Agreement

     1.1 Current Employee. Executive is currently employed by the Company.

     1.2 Benefits Upon Change In Control. The Company and Executive wish to set
forth the compensation and benefits which Executive shall be entitled to receive
in the event of a Change in Control or if Executive's employment with the
Company is terminated under the circumstances described herein following a
Change in Control.

     1.3 Consideration. The duties and obligations of the Company to Executive
under this Agreement shall be in consideration for Executive's past services to
the Company, Executive's continued employment with the Company, and Executive's
execution of a release in accordance with Section 4.1.

     1.4 Prior Agreement. This Agreement shall supersede any other agreement
relating to cash severance benefits and health benefits in the event of
Executive's severance from employment with the Company following a Change in
Control, including that certain Executive Severance Benefits Agreement between
the Company and Executive dated as of February 2, 1999 (the "Prior Agreement").
By executing this Agreement, Executive hereby waives (within the meaning of
Section 6.4 of the Prior Agreement) any rights Executive may currently have or
have in the future to any benefits of any sort under the Prior Agreement.

                                    ARTICLE 2

                   Option Acceleration Upon Change in Control

     In the event of a Change in Control, all options of Executive to purchase
the Company's common stock (or the stock of a successor to the Company by reason
of assumption or substitution of options) then outstanding shall, automatically
and without further action of the Company, become one hundred percent (100%)
vested and exercisable, and any restrictions with respect to restricted shares
of the Company's capital stock (or the stock of a successor to the Company by
reason of assumption or substitution of such shares) that Executive then holds
shall,

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automatically and without further action of the Company, lapse, in the case of
all such options and/or restrictions no later than five (5) business days before
the effective date of such Change in Control.

                                    ARTICLE 3

                               Severance Benefits

     3.1 Severance Benefits. If Executive's employment terminates due to an
Involuntary Termination Without Cause or a Constructive Termination, in any such
case occurring within thirteen (13) months following the effective date of a
Change in Control, such termination of employment will be deemed a Covered
Termination. A Covered Termination entitles Executive to receive the following
benefits set forth in Sections 3.2, 3.3 and 3.4.

     3.2 Base Salary. The Company shall pay to Executive an amount equal to
eighteen (18) months' Base Salary. Such severance amount shall be paid in cash
in a lump sum within thirty (30) days following the Covered Termination and
shall be subject to all required tax withholding.

     3.3 Bonus. The Company shall pay to Executive an amount equal to one
hundred and fifty percent (150%) of the annual bonus paid to the Executive in
the year immediately preceding the effective date of the Change in Control. Such
severance amount shall be paid in cash in a lump sum within thirty (30) days
following the Covered Termination and shall be subject to all required tax
withholding.

     3.4 Health Benefits. Provided that Executive elects continued coverage
under federal COBRA law, the Company shall pay the premiums of Executive's group
health insurance coverage, including coverage for Executive's eligible
dependents, for a maximum period of eighteen (18) months following a Covered
Termination; provided, however, that the Company shall pay premiums for
Executive's eligible dependents only for coverage for which those eligible
dependents were enrolled immediately prior to the Covered Termination. No
premium payments will be made following the effective date of Executive's
coverage by a health insurance plan of a subsequent employer. For the balance of
the period that Executive is entitled to coverage under federal COBRA law, if
any, Executive shall be entitled to maintain such coverage at Executive's own
expense.

     3.5 Mitigation. Except as otherwise specifically provided herein, Executive
shall not be required to mitigate damages or the amount of any payment provided
under this Agreement by seeking other employment or otherwise, nor shall the
amount of any payment provided for under this Agreement be reduced by any
compensation earned by Executive as a result of employment by another employer
or by any retirement benefits received by Executive after the date of the
Covered Termination.

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                                    ARTICLE 4

                     Limitations and Conditions On Benefits

     4.1 Release Prior To Payment Of Benefits. Upon the occurrence of a Covered
Termination, and prior to the payment of any benefits under this Agreement on
account of such Covered Termination, Executive shall execute a release (the
"Release") in the form attached hereto and incorporated herein as Exhibit A or
Exhibit B, as applicable. Such Release shall specifically relate to all of
Executive's rights and claims in existence at the time of such execution and
shall confirm Executive's obligations under the Company's standard form of
proprietary information and inventions agreement. It is understood that, as
specified in the applicable Release, Executive has a certain number of calendar
days to consider whether to execute such Release, and Executive may revoke such
Release within seven (7) calendar days after execution. In the event Executive
does not execute such Release within the applicable period, or if Executive
revokes such Release within the subsequent seven (7) day period, no benefits
shall be payable under this Agreement, and this Agreement shall be null and
void.

     4.2 Termination of Benefits. Benefits under this Agreement shall terminate
immediately if the Executive, at any time, violates any proprietary information
or confidentiality obligation to the Company.

     4.3 Non-Duplication of Benefits. Executive is not eligible to receive
benefits under this Agreement more than one time.

                                    ARTICLE 5

                               Parachute Payments

     5.1 Certain Additional Payments by the Company. Anything in this Agreement
to the contrary notwithstanding and except as set forth below, in the event it
shall be determined that any Payment would be subject to the Excise Tax, then
the Executive shall be entitled to receive from the Company an additional
payment (the "Gross-Up Payment") in an amount such that the net amount of the
Payment and the Gross-Up Payment retained by the Executive after the payment by
the Executive of all Excise Taxes (including any interest or penalties imposed
with respect to such taxes) on the Payment and all federal, state and local
income tax, employment tax and Excise Taxes (including any interest or penalties
imposed with respect to such taxes) on the Gross-Up Payment shall be equal to
the Payment.

     5.2 Determinations. Subject to the provisions of Section 5.3, all
determinations required to be made under this Article 5, including whether and
when a Gross-Up Payment is required and the amount of such Gross-Up Payment and
the assumptions to be utilized in arriving at such determination, shall be made
by the nationally recognized certified public accounting firm used by the
Company immediately prior to the effective date of the Change in Control or, if
such firm declines to serve, such other nationally recognized certified public
accounting firm as may be designated by the Executive (the "Accounting Firm").
The Accounting Firm shall provide detailed supporting calculations both to the
Company and the Executive within fifteen (15) business days of the receipt of
notice from the Executive that there

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has been a Payment, or such earlier time as is requested by the Company. All
fees and expenses of the Accounting Firm shall be borne solely by the Company.
Any determination by the Accounting Firm shall be binding upon the Company and
the Executive. Subject to Section 5.5 below, any Gross-Up Payment, as determined
pursuant to this Section 5.2, shall be paid by the Company to the Executive
within five (5) days of the receipt of the Accounting Firm's determination. For
purposes of making the calculations required by this Article 5, the Accounting
Firm may make reasonable assumptions and approximations concerning applicable
taxes and may rely on reasonable, good-faith interpretations concerning the
application of Sections 280G and 4999 of the Code. As a result of the
uncertainty in the application of Section 4999 of the Code at the time of the
initial determination by the Accounting Firm hereunder, it is possible that
Gross-Up Payments which will not have been made by the Company should have been
made ("Underpayment"), consistent with the calculations required to be made
hereunder. In the event that the Company exhausts its remedies pursuant to
Section 5.3 and the Executive thereafter is required to make a payment of any
Excise Tax, the Accounting Firm shall determine the amount of the Underpayment
that has occurred and any such Underpayment shall be promptly paid by the
Company to or for the benefit of the Executive.

     5.3 Contesting of Gross-Up Payment. The Executive shall notify the Company
in writing of any claim by the Internal Revenue Service that, if successful,
would require the payment by the Company of the Gross-Up Payment. Such
notification shall be given as soon as practicable but no later than ten (10)
business days after the Executive is informed in writing of such claim and shall
apprise the Company of the nature of such claim and the date on which such claim
is requested to be paid. The Executive shall not pay such claim prior to the
expiration of the thirty (30)-day period following the date on which it gives
such notice to the Company (or such shorter period ending on the date that any
payment of taxes with respect to such claim is due). If the Company notifies the
Executive in writing prior to the expiration of such period that it desires to
contest such claim, the Executive shall:

         (a) give the Company any information reasonably requested by the
Company relating to such claim,

         (b) take such action in connection with contesting such claim as the
Company shall reasonably request in writing from time to time, including,
without limitation, accepting legal representation with respect to such claim by
an attorney reasonably selected by the Company,

         (c) cooperate with the Company in good faith in order effectively to
contest such claim, and

         (d) permit the Company to participate in any proceedings relating to
such claim;

provided, however, that the Company shall bear and pay directly all costs and
expenses (including additional interest and penalties) incurred in connection
with such contest and shall indemnify and hold the Executive harmless, on an
after-tax basis, for any Excise Tax or income tax (including interest and
penalties with respect thereto) imposed as a result of such representation and
payment of costs and expenses. Without limitation on the foregoing

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provisions of this Section 5.3, the Company shall control all proceedings taken
in connection with such contest and, at its sole option, may pursue or forgo any
and all administrative appeals, proceedings, hearings and conferences with the
taxing authority in respect of such claim and may, at its sole option, either
direct the Executive to pay the tax claimed and sue for a refund or contest the
claim in any permissible manner, and the Executive agrees to prosecute such
contest to a determination before any administrative tribunal, in a court of
initial jurisdiction and in one or more appellate courts, as the Company shall
determine; provided, however, that if the Company directs the Executive to pay
such claim and sue for a refund, the Company shall advance the amount of such
payment to the Executive, on an interest-free basis and shall indemnify and hold
the Executive harmless, on an after-tax basis, from any Excise Tax or income tax
(including interest or penalties with respect thereto) imposed with respect to
such advance or with respect to any imputed income with respect to such advance;
and provided further, however, that any extension of the statute of limitations
relating to payment of taxes for the taxable year of the Executive with respect
to which such contested amount is claimed to be due is limited solely to such
contested amount. Furthermore, the Company's control of the contest shall be
limited to issues with respect to which a Gross-Up Payment would be payable
hereunder and the Executive shall be entitled to settle or contest, as the case
may be, any other issue raised by the Internal Revenue Service or any other
taxing authority.

     5.4 Refunds. If, after the receipt by the Executive of an amount advanced
by the Company pursuant to Section 5.3, the Executive becomes entitled to
receive any refund with respect to such claim, the Executive shall (subject to
the Company's complying with the requirements of Section 5.3) promptly pay to
the Company the amount of such refund (together with any interest paid or
credited thereon after taxes applicable thereto). If, after the receipt by the
Executive of an amount advanced by the Company pursuant to Section 5.3, a
determination is made that the Executive shall not be entitled to any refund
with respect to such claim and the Company does not notify the Executive in
writing of its intent to contest such denial of refund prior to the expiration
of thirty (30) days after such determination, then such advance shall be
forgiven and shall not be required to be repaid and the amount of such advance
shall offset, to the extent thereof, the amount of Gross-Up Payment required to
be paid.

     5.5 Withholding. Notwithstanding any other provision of this Article 5, the
Company may withhold and pay over to the Internal Revenue Service for the
benefit of the Executive all or any portion of the Gross-Up Payment that it
determines in good faith that it is or may be in the future required to
withhold, and the Executive hereby consents to such withholding.

                                    ARTICLE 6

                                   Definitions

     For purposes of the Agreement, the following terms are defined as follows:

     6.1 "Base Salary" means Executive's annual base salary as in effect during
the last regularly scheduled payroll period immediately preceding the Covered
Termination.

     6.2 "Board" means the Board of Directors of the Company.

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     6.3 "Cause" means that, in the reasonable determination of the Company,
Executive:

         (a) has committed an act that materially injures the business of the
Company;

         (b) has refused or failed to follow lawful and reasonable directions of
the Board or the appropriate individual to whom Executive reports;

         (c) has willfully or habitually neglected Executive's duties for the
Company; or

         (d) has been convicted of a felony involving moral turpitude that is
likely to inflict or has inflicted material injury on the business of the
Company.

         Notwithstanding the foregoing, Cause shall not exist based on conduct
described in clause (b) or clause (c) unless the conduct described in such
clause has not been cured within fifteen (15) days following Executive's receipt
of written notice from the Company or the Board, as the case may be, specifying
the particulars of the conduct constituting Cause.

     6.4 "Change in Control" means

         (a) a sale of substantially all of the assets of the Company;

         (b) a merger or consolidation in which the Company is not the surviving
corporation (other than a merger or consolidation in which shareholders
immediately before the merger or consolidation have, immediately after the
merger or consolidation, equal or greater stock voting power);

         (c) a reverse merger in which the Company is the surviving corporation
but the shares of the Company's common stock outstanding immediately preceding
the merger are converted by virtue of the merger into other property, whether in
the form of securities, cash or otherwise (other than a reverse merger in which
shareholders immediately before the merger have, immediately after the merger,
greater stock voting power); or

         (d) any transaction or series of related transactions in which in
excess of 50% of the Company's voting power is transferred.

     6.5 "Code" means the Internal Revenue Code of 1986, as amended.

     6.6 "Company" means CV Therapeutics, Inc. or, following a Change in
Control, the surviving entity resulting from such transaction.

     6.7 "Constructive Termination" means that Executive voluntarily terminates
employment within thirteen (13) months following the effective date of a Change
in Control after any of the following are undertaken without Executive's express
written consent:

         (a) the assignment to Executive of any duties or responsibilities which
results in a significant diminution in Executive's function as in effect
immediately prior to the effective

                                        6

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date of the Change in Control; provided, however, that a mere change in
Executive's title or reporting relationships shall not constitute a Constructive
Termination;

         (b) a reduction by the Company in Executive's annual base salary, as in
effect on the effective date of the Change in Control or as increased
thereafter;

         (c) any failure by the Company to continue in effect any benefit plan
or program, including fringe benefits, incentive plans and plans with respect to
the receipt of securities of the Company, in which Executive is participating
immediately prior to the effective date of the Change in Control (hereinafter
referred to as "Benefit Plans"); or the taking of any action by the Company that
would adversely affect Executive's participation in or reduce Executive's
benefits under the Benefit Plans; provided, however, that a "Constructive
Termination" shall not exist under this paragraph following a Change in Control
if the Company offers a range of benefit plans and programs which, taken as a
whole, are comparable to the Benefit Plans;

         (d) a relocation of Executive's business office to a location more than
twenty (20) miles from the location at which Executive performs duties as of the
effective date of the Change in Control, except for required travel by Executive
on the Company's business to an extent substantially consistent with Executive's
business travel obligations prior to the Change in Control; provided, however,
that if Executive performs sales functions for the Company, a change of sales
territory shall not constitute a basis for Constructive Termination so long as
the Executive's business office is not relocated as provided above;

         (e) a material breach by the Company of any provision of this
Agreement; or

         (f) any failure by the Company to obtain the assumption of this
Agreement by any successor or assign of the Company.

The termination of Executive's employment as a result of Executive's death or
disability will not be deemed to be a Constructive Termination.

     6.8  "Covered Termination" means an Involuntary Termination Without Cause
or a Constructive Termination, in any such case occurring within thirteen (13)
months following the effective date of a Change in Control.

     6.9  "Excise Tax" shall mean the excise tax imposed by Section 4999 of the
Code, together with any interest or penalties imposed with respect to such
excise tax.

     6.10 "Involuntary Termination Without Cause" means Executive's dismissal or
discharge other than for Cause. The termination of Executive's employment as a
result of Executive's death or disability will not be deemed to be an
Involuntary Termination Without Cause.

     6.11 A "Payment" shall mean any payment or distribution in the nature of
compensation (within the meaning of Section 280G(b)(2) of the Code) to or for
the benefit of the Executive, whether paid or payable pursuant to this Agreement
or otherwise.

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                                    ARTICLE 7

                               General Provisions

     7.1 Employment Status. This Agreement does not constitute a contract of
employment or impose upon Executive any obligation to remain as an employee, or
impose on the Company any obligation (i) to retain Executive as an employee,
(ii) to change the status of Executive as an at-will employee, or (iii) to
change the Company's policies regarding termination of employment.

     7.2 Notices. Any notices provided hereunder must be in writing, and such
notices or any other written communication shall be deemed effective upon the
earlier of personal delivery (including personal delivery by facsimile) or the
third day after mailing by first class mail, to the Company at its primary
office location and to Executive at Executive's address as listed in the
Company's payroll records. Any payments made by the Company to Executive under
the terms of this Agreement shall be delivered to Executive either in person or
at the address as listed in the Company's payroll records.

     7.3 Severability. Whenever possible, each provision of this Agreement will
be interpreted in such manner as to be effective and valid under applicable law,
but if any provision of this Agreement is held to be invalid, illegal or
unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect
any other provision or any other jurisdiction, but this Agreement will be
reformed, construed and enforced in such jurisdiction as if such invalid,
illegal or unenforceable provisions had never been contained herein.

     7.4 Waiver. If either party should waive any breach of any provisions of
this Agreement, he or it shall not thereby be deemed to have waived any
preceding or succeeding breach of the same or any other provision of this
Agreement.

     7.5 Arbitration. Unless otherwise prohibited by law or specified below, all
disputes, claims and causes of action, in law or equity, arising from or
relating to this Agreement or its enforcement, performance, breach, or
interpretation shall be resolved solely and exclusively by final and binding
arbitration held in San Francisco County, California through Judicial
Arbitration & Mediation Services/Endispute ("JAMS") under the then existing JAMS
arbitration rules. However, nothing in this Section is intended to prevent
either party from obtaining injunctive relief in court to prevent irreparable
harm pending the conclusion of any such arbitration. The Company will pay the
direct costs and expenses of any such arbitration, including the fees and costs
of the arbitrator. Each party in any such arbitration shall be responsible for
its own attorneys' fees and related costs and necessary disbursements; provided,
however, that in the event one party refuses to arbitrate and the other party
seeks to compel arbitration by court order, if such other party prevails, except
as may be prohibited by law, it shall be entitled to recover reasonable
attorneys' fees and related costs and necessary disbursements. Pursuant to
California Civil Code Section 1717, each party warrants that it was represented
by counsel in the negotiation and execution of this Agreement, including the
attorneys' fees provision herein.

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     7.6  Complete Agreement. This Agreement, including Exhibit A and Exhibit B,
constitutes the entire agreement between Executive and the Company and is the
complete, final, and exclusive embodiment of their agreement with regard to this
subject matter, wholly superseding all written and oral agreements with respect
to cash severance benefits and health benefits to Executive in the event of
employment termination (including the Prior Agreement) other than any
outstanding loans by the Company to Executive. It is entered into without
reliance on any promise or representation other than those expressly contained
herein.

     7.7  Amendment Or Termination Of Agreement. This Agreement may be changed
or terminated only upon the mutual written consent of the Company and Executive.
The written consent of the Company to a change or termination of this Agreement
must be signed by an executive officer of the Company after such change or
termination has been approved by the Board.

     7.8  Counterparts. This Agreement may be executed in separate counterparts,
any one of which need not contain signatures of more than one party, but all of
which taken together will constitute one and the same Agreement.

     7.9  Headings. The headings of the Articles and Sections hereof are
inserted for convenience only and shall not be deemed to constitute a part
hereof nor to affect the meaning thereof.

     7.10 Successors And Assigns. This Agreement is intended to bind and inure
to the benefit of and be enforceable by Executive, and the Company, and any
surviving entity resulting from a Change in Control and upon any other person
who is a successor by merger, acquisition, consolidation or otherwise to the
business formerly carried on by the Company, and their respective successors,
assigns, heirs, executors and administrators, without regard to whether or not
such person actively assumes any rights or duties hereunder; provided, however,
that Executive may not assign any duties hereunder and may not assign any rights
hereunder without the written consent of the Company, which consent shall not be
withheld unreasonably.

     7.11 Choice Of Law. All questions concerning the construction, validity and
interpretation of this Agreement will be governed by the law of the State of
California, without regard to such state's conflict of laws rules.

     7.12 Non-Publication. The parties mutually agree not to disclose publicly
the terms of this Agreement except to the extent that disclosure is mandated by
applicable law or regulation or to respective advisors (e.g., attorneys,
accountants).

     7.13 Construction Of Agreement. In the event of a conflict between the text
of the Agreement and any summary, description or other information regarding the
Agreement, the text of the Agreement shall control.

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     In Witness Whereof, the parties have executed this Agreement on the
Effective Date written above.

Cv Therapeutics, Inc.                              Brent K. Blackburn


By: /s/ Louis G. Lange                             /s/ Brent K. Blackburn
    ---------------------------------------        -----------------------------
Name: Louis G. Lange
      -------------------------------------
Title: Chairman & Chief Executive Officer
       ------------------------------------

Exhibit A:  Release (Individual Termination)
Exhibit B:  Release (Group Termination)

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                                    Exhibit A

                                     RELEASE
                            (Individual Termination)

     Certain capitalized terms used in this Release are defined in the Amended
and Restated Executive Severance Benefits Agreement (the "Agreement") which I
have executed and of which this Release is a part.

     I hereby confirm my obligations under the Company's proprietary information
and inventions agreement.

     I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A general release does not extend
to claims which the creditor does not know or suspect to exist in his favor at
the time of executing the release, which if known by him must have materially
affected his settlement with the debtor." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to my release of any claims I may
have against the Company.

     Except as otherwise set forth in this Release, I hereby release, acquit and
forever discharge the Company, its parents and subsidiaries, and their officers,
directors, agents, servants, employees, shareholders, successors, assigns and
affiliates, of and from any and all claims, liabilities, demands, causes of
action, costs, expenses, attorneys fees, damages, indemnities and obligations of
every kind and nature, in law, equity, or otherwise, known and unknown,
suspected and unsuspected, disclosed and undisclosed (other than any claim for
indemnification I may have as a result of any third party action against me
based on my employment with the Company), arising out of or in any way related
to agreements, events, acts or conduct at any time prior to the date I execute
this Release, including, but not limited to: all such claims and demands
directly or indirectly arising out of or in any way connected with my employment
with the Company or the termination of that employment, including but not
limited to, claims of intentional and negligent infliction of emotional
distress, any and all tort claims for personal injury, claims or demands related
to salary, bonuses, commissions, stock, stock options, or any other ownership
interests in the Company, vacation pay, fringe benefits, expense reimbursements,
severance pay, or any other form of disputed compensation; claims pursuant to
any federal, state or local law or cause of action including, but not limited
to, the federal Civil Rights Act of 1964, as amended; the federal Age
Discrimination in Employment Act of 1967, as amended ("ADEA"); the federal
Employee Retirement Income Security Act of 1974, as amended; the federal
Americans with Disabilities Act of 1990; the California Fair Employment and
Housing Act, as amended; tort law; contract law; statutory law; common law;
wrongful discharge; discrimination; fraud; defamation; emotional distress; and
breach of the implied covenant of good faith and fair dealing; provided,
however, that nothing in this paragraph shall be construed in any way to release
the Company from its obligation to indemnify me pursuant to the Company's
indemnification obligation pursuant to agreement or applicable law.

                                        1

<PAGE>

     I acknowledge that I am knowingly and voluntarily waiving and releasing any
rights I may have under ADEA. I also acknowledge that the consideration given
under the Agreement for the waiver and release in the preceding paragraph hereof
is in addition to anything of value to which I was already entitled. I further
acknowledge that I have been advised by this writing, as required by the ADEA,
that: (A) my waiver and release do not apply to any rights or claims that may
arise on or after the date I execute this Release; (B) I have the right to
consult with an attorney prior to executing this Release; (C) I have twenty-one
(21) days to consider this Release (although I may choose to voluntarily execute
this Release earlier); (D) I have seven (7) days following the execution of this
Release by the parties to revoke the Release; and (E) this Release shall not be
effective until the date upon which the revocation period has expired, which
shall be the eighth day after this Release is executed by me.

                                                      Brent K. Blackburn


                                                      __________________________
                                                      Date:_____________________

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                                    Exhibit B

                                     RELEASE
                               (Group Termination)

     Certain capitalized terms used in this Release are defined in the Amended
and Restated Executive Severance Benefits Agreement (the "Agreement") which I
have executed and of which this Release is a part.

     I hereby confirm my obligations under the Company's proprietary information
and inventions agreement.

     I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A general release does not extend
to claims which the creditor does not know or suspect to exist in his favor at
the time of executing the release, which if known by him must have materially
affected his settlement with the debtor." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to my release of any claims I may
have against the Company.

     Except as otherwise set forth in this Release, I hereby release, acquit and
forever discharge the Company, its parents and subsidiaries, and their officers,
directors, agents, servants, employees, shareholders, successors, assigns and
affiliates, of and from any and all claims, liabilities, demands, causes of
action, costs, expenses, attorneys fees, damages, indemnities and obligations of
every kind and nature, in law, equity, or otherwise, known and unknown,
suspected and unsuspected, disclosed and undisclosed (other than any claim for
indemnification I may have as a result of any third party action against me
based on my employment with the Company), arising out of or in any way related
to agreements, events, acts or conduct at any time prior to the date I execute
this Release, including, but not limited to: all such claims and demands
directly or indirectly arising out of or in any way connected with my employment
with the Company or the termination of that employment, including but not
limited to, claims of intentional and negligent infliction of emotional
distress, any and all tort claims for personal injury, claims or demands related
to salary, bonuses, commissions, stock, stock options, or any other ownership
interests in the Company, vacation pay, fringe benefits, expense reimbursements,
severance pay, or any other form of disputed compensation; claims pursuant to
any federal, state or local law or cause of action including, but not limited
to, the federal Civil Rights Act of 1964, as amended; the federal Age
Discrimination in Employment Act of 1967, as amended ("ADEA"); the federal
Employee Retirement Income Security Act of 1974, as amended; the federal
Americans with Disabilities Act of 1990; the California Fair Employment and
Housing Act, as amended; tort law; contract law; statutory law; common law;
wrongful discharge; discrimination; fraud; defamation; emotional distress; and
breach of the implied covenant of good faith and fair dealing; provided,
however, that nothing in this paragraph shall be construed in any way to release
the Company from its obligation to indemnify me pursuant to the Company's
indemnification obligation pursuant to agreement or applicable law.

     I acknowledge that I am knowingly and voluntarily waiving and releasing any
rights I may have under ADEA. I also acknowledge that the consideration given
under the Agreement

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for the waiver and release in the preceding paragraph hereof is in addition to
anything of value to which I was already entitled. I further acknowledge that I
have been advised by this writing, as required by the ADEA, that: (A) my waiver
and release do not apply to any rights or claims that may arise on or after the
date I execute this Release; (B) I have the right to consult with an attorney
prior to executing this Release; (C) I have forty-five (45) days to consider
this Release (although I may choose to voluntarily execute this Release
earlier); (D) I have seven (7) days following the execution of this Release by
the parties to revoke the Release; (E) this Release shall not be effective until
the date upon which the revocation period has expired, which shall be the eighth
day after this Release is executed by me; and (F) I have received with this
Release a detailed list of the job titles and ages of all employees who were
terminated in this group termination and the ages of all employees of the
Company in the same job classification or organizational unit who were not
terminated.

                                                 Brent K. Blackburn

                                                 _______________________________
                                                 Date:__________________________

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