MODIFICATION AND EXTENSION AGREEMENT

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                                                                    EXHIBIT 10.6

                      MODIFICATION AND EXTENSION AGREEMENT

            THIS MODIFICATION AND EXTENSION AGREEMENT ("Agreement") is made as

of the 2nd day of January, 2004 by and among LightFirst Inc. ("Borrower"),

Martin P. Gilmore ("Guarantor"), and Richard R. Gritzke ("Lender").

                                    RECITALS

            A. Borrower owes the sum of SIX HUNDRED TWENTY THOUSAND DOLLARS

pursuant to two promissory notes: the Promissory Note (the "First Note") dated

July 15, 2002 in the amount of Four Hundred Twenty Thousand Dollars, and the

Promissory Note (the "Second Note") dated November 2, 2002, in the amount of Two

Hundred Thousand Dollars. The First Note and the Second Note are hereinafter

referred to collectively as the "Notes".

            B. The maturity date of the First Note was extended and modified

from the 90th day after July 15, 2002 to January 2, 2004 in accordance with that

certain Modification and Extension Agreement dated May 30, 2003. The maturity

date of the Second Note was extended and modified from the 90th day after

November 2, 2002 to January 2, 2004 in accordance with that certain Modification

and Extension Agreement dated May 30, 2003.