Exhibit 10.4

ALTIGEN COMMUNICATIONS, INC.        1999 STOCK PLAN        (AS AMENDED ON JUNE 2, 1999 AND AUGUST 15, 2002)

1.Purposes of the Plan.    The purposes of this 1999 Stock Plan are:



Options
granted under the Plan may be Incentive Stock Options or Nonstatutory Stock Options, as determined by the Administrator at the time of grant. Stock Purchase Rights may also be
granted under the Plan.

2.Definitions.    As used herein, the following definitions shall apply:



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3.Stock Subject to the Plan.    Subject to the provisions of Section 13 of the
Plan, the maximum aggregate number of Shares which may be optioned and sold under the Plan is 2,096,247 Shares (post one-for-1.66965 stock split), plus an annual increase to be
added on the first day of the Company's fiscal year (beginning in 2000) equal to the lesser of (i) 1,796,783 Shares (post one-for-1.66965 stock split), or
(ii) five percent (5%) of the outstanding Shares on such date, or (iii) such lesser amount as determined by the Board of Directors. The Shares may be authorized, but unissued, or
reacquired Common Stock.

If
an Option or Stock Purchase Right expires or becomes unexercisable without having been exercised in full, or is surrendered pursuant to an Option Exchange Program, the unpurchased
Shares which were subject thereto shall become available for future grant or sale under the Plan (unless the Plan has
terminated); provided, however, that Shares that have actually been issued under the Plan, whether upon exercise of an Option or Right, shall
not be returned to the Plan and shall not become available for future distribution under the Plan, except that if Shares of Restricted Stock are repurchased by the Company at their original purchase
price, such Shares shall become available for future grant under the Plan.

4.Administration of the Plan.



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5.Eligibility.    Nonstatutory Stock Options and Stock Purchase Rights may be granted
to Service Providers. Incentive Stock Options may be granted only to Employees.

6.Limitations.



7.Term of Plan.    Subject to Section 19 of the Plan, the Plan shall become
effective upon its adoption by the Board. It shall continue in effect for a term of ten (10) years unless terminated earlier under Section 15 of the Plan.

8.Term of Option.    The term of each Option shall be stated in the Option Agreement;
provided, however, that the term shall be no more than ten (10) years from the date of grant thereof. In the case of an Incentive Stock Option, the term shall be ten (10) years from the
date of grant or such shorter term as may be provided in the Option Agreement. Moreover, in the case of an Incentive Stock Option granted to an Optionee who, at the time the Incentive Stock Option is
granted, owns stock representing more than ten percent (10%) of the total combined voting power of all classes of stock of the Company or any Parent or Subsidiary, the term of the Incentive Stock
Option shall be five (5) years from the date of grant or such shorter term as may be provided in the Option Agreement.

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9.Option Exercise Price and Consideration.



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10.Exercise of Option.



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11.Stock Purchase Rights.



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12.Limited Transferability of Options and Stock Purchase Rights.    Unless determined
otherwise by the Administrator, Options and Stock Purchase Rights may not be sold, pledged, assigned, hypothecated, transferred, or disposed of in any manner other than by will or the laws of descent
and distribution, and may be exercised during the lifetime of the Optionee, only by the Optionee. If the Administrator in its sole discretion makes an Option transferable, such Option or Stock
Purchase Right may only be transferred (i) by will, (ii) by the laws of descent and distribution, or (iii) as permitted by Rule 701 of the Securities Act of 1933, as
amended.

13.Adjustments Upon Changes in Capitalization, Dissolution, Merger or Asset Sale.



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14.Date of Grant.    The date of grant of an Option or Stock Purchase Right shall be,
for all purposes, the date on which the Administrator makes the determination granting such Option or Stock Purchase
Right, or such other later date as is determined by the Administrator. Notice of the determination shall be provided to each Optionee within a reasonable time after the date of such grant.

15.Amendment and Termination of the Plan.



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16.Conditions Upon Issuance of Shares.



17.Inability to Obtain Authority.    The inability of the Company to obtain authority
from any regulatory body having jurisdiction, which authority is deemed by the Company's counsel to be necessary to the
lawful issuance and sale of any Shares hereunder, shall relieve the Company of any liability in respect of the failure to issue or sell such Shares as to which such requisite authority shall not have
been obtained.

18.Reservation of Shares.    The Company, during the term of this Plan, will at all
times reserve and keep available such number of Shares as shall be sufficient to satisfy the requirements of the Plan.

19.Stockholder Approval.    The Plan shall be subject to approval by the stockholders
of the Company within twelve (12) months after the date the Plan is adopted. Such stockholder approval shall be obtained in the manner and to the degree required under Applicable Laws.

20.Information to Optionees.    The Company shall provide to each Optionee and to
each individual who acquires Shares pursuant to the Plan, not less frequently than annually during the period such participant has one or more Options outstanding, and, in the case of an individual
who acquires Shares pursuant to the Plan, during the period such individual owns such Shares, copies of annual financial statements. The Company shall not be required to provide such statements to key
employees whose duties in connection with the Company assure their access to equivalent information.

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ALTIGEN COMMUNICATIONS, INC.        AMENDED AND RESTATED 1999 STOCK PLAN        STOCK OPTION AGREEMENT

Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Option Agreement.

I.    NOTICE OF STOCK OPTION GRANT

«NAME»

The
undersigned Optionee has been granted an Option to purchase Common Stock of the Company, subject to the terms and conditions of the Plan and this Option Agreement, as follows:

Grant NumberDate of GrantVesting Commencement DateExercise Price per ShareTotal Number of Shares GrantedTotal Exercise PriceType of Option:

____ Incentive Stock Option____ Nonstatutory Stock OptionTerm/Expiration Date:




25%
of the Shares subject to the Option shall vest twelve (12) months after the Vesting Commencement Date set forth above and 1/48 of the Shares subject to the Option shall vest
each month thereafter, subject to Optionee continuing as a Service Provider on such dates.



This
Option shall be exercisable for three (3) months after Optionee ceases to be a Service Provider. Upon Optionee's death or disability, this Option may be exercised for such
longer period as provided in the Plan. In no event may Optionee exercise this Option after the Term/Expiration Date as provided above.

II.    AGREEMENT

1.Grant of Option.    The Plan Administrator of the Company hereby grants to the
Optionee named in the Notice of Grant (the "Optionee"), an option (the "Option") to purchase the number of Shares set forth in the Notice of Grant, at the exercise price per Share set forth in the
Notice of Grant (the "Exercise Price"), and subject to the terms and conditions of the Plan, which is incorporated herein by reference. Subject to Section 15(c) of the Plan, in the event of a
conflict between the terms and conditions of the Plan and this Option Agreement, the terms and conditions of the Plan shall prevail.

If
designated in the Notice of Grant as an Incentive Stock Option ("ISO"), this Option is intended to qualify as an Incentive Stock Option as defined in Section 422 of the Code.
Nevertheless, to the

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extent
that it exceeds the $100,000 rule of Code Section 422(d), this Option shall be treated as a Nonstatutory Stock Option ("NSO").

2.Exercise of Option.



3.Method of Payment.    Payment of the aggregate Exercise Price shall be by any of
the following, or a combination thereof, at the election of the Optionee:



4.Restrictions on Exercise.    This Option may not be exercised until such time as
the Plan has been approved by the shareholders of the Company, or if the issuance of such Shares upon such exercise or the method of payment of consideration for such shares would constitute a
violation of any Applicable Law.

5.Non-Transferability of Option.    This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution and may be exercised during the lifetime of Optionee only by Optionee. The terms of the Plan and this Option Agreement shall
be binding upon the executors, administrators, heirs, successors and assigns of the Optionee.

6.Term of Option.    This Option may be exercised only within the term set out in the
Notice of Grant, and may be exercised during such term only in accordance with the Plan and the terms of this Option.

7.Tax Obligations.



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8.Entire Agreement; Governing Law.    The Plan is incorporated herein by reference.
The Plan and this Option Agreement constitute the entire agreement of the parties with respect to the subject matter
hereof and supersede in their entirety all prior undertakings and agreements of the Company and Optionee with respect to the subject matter hereof, and may not be modified adversely to the Optionee's
interest except by means of a writing signed by the Company and Optionee. This agreement is governed by the internal substantive laws but not the choice of law rules of California.

9.No Guarantee of Continued Service.    OPTIONEE ACKNOWLEDGES AND AGREES THAT THE
VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY CONTINUING AS A SERVICE PROVIDER AT THE WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS OPTION
OR ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN
EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT INTERFERE IN ANY WAY WITH OPTIONEE'S RIGHT OR THE COMPANY'S
RIGHT TO TERMINATE OPTIONEE'S RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

[Remainder of Page Intentionally Left Blank.]

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Optionee acknowledges receipt of a copy of the Plan and represents that he or she is familiar with the terms and provisions thereof, and hereby accepts this Option subject to all of the
terms and provisions thereof. Optionee has reviewed the Plan and this Option in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Option and fully
understands all provisions of the Option. Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the
Plan or this Option. Optionee further agrees to notify the Company upon any change in the residence address indicated below.

|OPTIONEE:         |  | AltiGen Communications, Inc.
|----------------- |  | ----------------------------
|Signature         |  | By                          
|Print Name        |  | Name                        
|                  |  | Title                       
|Residence Address |  |                             

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EXHIBIT AEXERCISE NOTICE AND AGREEMENT

AltiGen
Communications, Inc.
47427 Fremont Blvd.
Fremont, CA 94538

Attention:
Stock Option Plan Administrator



|Name of Optionee:                                              |  |           
|-------------------------------------------------------------- |  | ----------
|Optionee's Address:                                            |  |           
|Optionee's Social Security Number:                             |  | -        -
|Date of Option Agreement:                                      |  |           
|Exercise Date:                                                 |  |           
|The Shares Purchased are Incentive Stock Options:
(circle one) |  | Yes / No  
|Number of Shares Purchased Pursuant to this Notice:            |  |           
|Exercise Price per Share:                                      |  | $         
|Aggregate Exercise Price:                                      |  | $         
|Add Withholding:                                               |  | $         
|Amount of Check Enclosed:                                      |  | $         

1.Exercise of Option.    Pursuant to the Amended and Restated 1999 Stock Option Plan
(the "Plan") of AltiGen Communications, Inc., a Delaware corporation (the "Company") and the Stock Option Agreement ("Option Agreement") entered into as of the date set forth above between the
undersigned Optionee and the Company, Optionee hereby elects, effective as of the date of this notice, to exercise Optionee's option to purchase the number of shares of common stock (the "Shares") of
the Company indicated above.

2.Payment; Taxes.    Enclosed is Optionee's check in the amount indicated above,
which is the full exercise price for the Shares plus any applicable withholding of taxes. Before the Company issues the Shares, Optionee shall make appropriate arrangements with the Company for
payment of Optionee's tax obligation as a result of this Option exercise if such withholding is not included in the above payment.

3.Deemed Date of Exercise.    The date of exercise shall be deemed to be the first
date after which this Notice is filed with Company upon which Shares become eligible for issuance to Optionee under applicable state and federal laws and regulatory requirements.

4.Compliance with Laws.    Optionee understands and acknowledges that the purchase
and sale of the Shares may be subject to approval under the state and federal securities laws and other laws and, notwithstanding any other provision of the Option Agreement to the contrary, the
exercise of any rights to purchase Shares is expressly conditioned upon approval (if necessary) and compliance with all such laws.

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5.Representations of Optionee.    Optionee represents and warrants to the Company, as
follows:



6.Refusal to Transfer.    The Company shall not be required (a) to transfer on
its books any Shares that have been sold or otherwise transferred in violation of any of the provisions of this Agreement, the Option Agreement, or the Plan or (b) to treat as owner of such
Shares or to accord the right to vote or receive dividends to any purchaser or other transferee to whom such Shares shall have been so transferred.

7.Tax Consultation.    Optionee understands that Optionee may suffer adverse tax
consequences as a result of Optionee's purchase or disposition of the Shares. Optionee represents that Optionee has consulted with any tax consultants Optionee deems advisable in connection with the
purchase or disposition of the Shares and that Optionee is not relying on the Company for any tax advice.

8.Entire Agreement.    The Plan and the Option Agreement are incorporated herein by
reference. This Agreement, the Plan, and the Option Agreement constitute the entire agreement of the parties and supersede in their entirety all prior undertakings and agreements of the Company and
Optionee with respect to the subject matter hereof.

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|Submitted by: |  | Accepted by:                                        
|------------- |  | ----------------------------------------------------
|"OPTIONEE":   |  | "COMPANY"                                           
|              |  | AltiGen Communications, Inc.,
a Delaware corporation
|Signature     |  | By                                                  
|Print Name    |  | Name                                                
|              |  | Title                                               

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