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                                                                   EXHIBIT 10.12


[LightFirst Inc. Letterhead]





[Date]

[Employee Name]
[Employee Address]
[Employee Address]

Dear [Employee Name]:

You have elected to defer receipt of certain amounts which would otherwise have
become payable to you by LightFirst Inc. (the "Company") in the past or which
will otherwise become payable to you in the future in connection with your
employment with the Company. This letter sets forth the terms of the deferral
facility.

1.   This agreement shall cover the amount of [$Amount] (the "Deferred Amount"),
     which would otherwise be payable to you in cash by the Company in
     connection with your employment during the period(s) covered by this
     agreement.

2.   This agreement replaces and supersedes the Deferred Compensation letter
     issued to you by the Company on [Date] and acknowledged by you on [Date]
     and any other instrument whereby compensation that would otherwise be
     payable to you has been deferred prior to the date of this letter. The
     Deferred Amount, as defined herein, includes all amounts previously
     deferred by other instruments and represents the full amount owed to you by
     the Company as of the date of this letter. All other instruments whereby
     compensation has been deferred prior to the date of this letter are hereby
     rendered null and void.

3.   Subject to the terms and conditions of this Agreement, the Company shall
     establish and maintain on your behalf an account on the Company's books and
     records (the "Deferred Payment Account") which shall entitle you to receive
     on the Due Date, as defined herein, a lump-sum payment of the Deferred
     Amount, less any amounts withheld pursuant to federal, state, and local tax
     withholding requirements.

4.   The Due Date shall be the earlier of January 2, 2005 or 10 days following
     the successful completion and closing of the Company's initial public
     offering as described in the Company's Registration Statement as filed with
     the Securities and Exchange Commission on Form S-1, as amended on February
     13, 2004, bearing Registration Number 333-107769.


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5.   In the event of your termination of employment with the Company for any
     reason prior to the payout of the Deferred Amount, the Company shall pay to
     you, or your estate in the event of your death, the full Deferred Amount on
     the Due Date.

6.   Nothing in this letter agreement shall be deemed to create a trust or
     segregated asset account of any nature, and no money or other thing of
     value shall be separately held by the Company in connection with its
     obligation to pay the Deferred Amount hereunder. The attempt by any person
     to anticipate, hypothecate or otherwise receive value in respect of such
     obligation prior to the Due Date under the terms of this letter agreement
     shall be null and void and of no force or effect.

Please indicate your acknowledgment of and agreement to all of the foregoing by
signing the enclosed copy of this letter and returning it to Martin P. Gilmore,
Chief Executive Officer of the Company, at the address below or in person.

                                                    Very truly yours,

                                                    LIGHTFIRST INC.

                                                    by:
                                                       -------------------------
                                                       Martin P. Gilmore
                                                       Chief Executive Officer

ACKNOWLEDGED AND AGREED TO:


-----------------------------------
         [Employee Name]

Date:
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