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                                                                     EXHIBIT 4.1

VOYAGER ONE, INC.
859 WEST END COURT - SUITE I
VERNON HILLS, IL 60061
PHONE: (847) 984-6200
FAX: (847) 984-6201

December 31, 2004                                                 HAND DELIVERED
                                                                  --------------
Mr. John Lichter
President/CEO
Quest Manufacturing, Inc.
2503 Spring Ridge Drive
Unit F
P.O. Box 430
Spring Grove, IL  60081

RE:   Repayment of proceeds pursuant to Asset Purchase Agreement

Dear Mr. Lichter:

Pursuant to Paragraph 5(b)(2) of the Asset Purchase Agreement between Quest
Manufacturing, Inc. and Silicon Film Technologies, Incorporated, dated February
1, 2003, the outstanding balance of $305,000 is to be payable to Quest
Manufacturing, Inc. no later than December 31, 2004. This unpaid balance has
accrued interest at 6% per annum. This will confirm that you have agreed, on
behalf of Quest Manufacturing, Inc., to extend the payment date to March 31,
2005. The outstanding balance will continue to accrue interest at the rate of
six percent (6%) per annum. Please confirm this agreement by signing and dating
this letter below.

Very truly yours,

/s/ Sebastien DuFort
--------------------
Sebastien DuFort
President
Voyager One, Inc.

I, John Lichter, President and CEO of Quest Manufacturing, Inc., hereby confirm
that I have extended the payment due date of outstanding funds of $305,000 plus
interest as indicated above to March 31, 2005.


12/31/04                       /s/ John Lichter
--------                       ----------------
Date                           John Lichter
                               President/CEO
                               Quest Manufacturing

SD/cap

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Quest Manufacturing, Inc.
2503 Spring Ridge Drive
Unit F
P.O. Box 430
Spring Grove, IL  60081



March 23, 2005                                                    HAND DELIVERED
                                                                  --------------



Mr. Sebastien Dufort
President
Voyager One, Inc.
859 West End Court-Suite I
Vernon Hills, IL  60061

Re:  Repayment of Proceeds Pursuant to Asset Purchase Agreement

Dear Mr. Dufort:

This will confirm that I have agreed, on behalf of Quest Manufacturing, Inc.
(Quest), to extend the payment date of the outstanding balance of $305,000 owed
Quest pursuant to Paragraph 5(b)(2) of the Asset Purchase Agreement dated
February 1, 2003 from March 31, 2005 to July 31, 2005. This unpaid balance has
accrued interest at 6% per annum. You have agreed that the outstanding balance
will continue to accrue interest at the rate of six percent (6%) per annum.

Very truly yours,

/S/ JOHN A. LICHTER
--------------------------
John Lichter
President/CEO
Quest Manufacturing, Inc.


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Quest Manufacturing, Inc.
2503 Spring Ridge Drive
Unit F
P.O. Box 430
Spring Grove, IL  60081


August 9, 2005                                                   HAND DELIVERED
                                                                 --------------


Mr. Sebastien Dufort
President
Voyager One, Inc.
859 West End Court-Suite I
Vernon Hills, IL  60061

Re:  Repayment of Proceeds Pursuant to Asset Purchase Agreement

Dear Mr. Dufort:

This will confirm that I have agreed, on behalf of Quest Manufacturing, Inc.
(Quest), to extend the payment date of the outstanding balance of $305,000 owed
Quest pursuant to paragraph 5(b)(2) of the Asset Purchase Agreement dated
February 1, 2003 from July 31, 2005 (as previously extended in my letter of
March 23, 2005) to anytime on demand after August 9, 2005. This unpaid balance
has accrued interest at 6% per annum. You have agreed that the outstanding
balance will continue to accrue interest at the rate of six percent (6%) per
annum.

Very truly yours,

/S/ JOHN LICHTER
-------------------------
John Lichter
President/CEO
Quest Manufacturing, Inc.