EXHIBIT 10.6

                              AMENDED AND RESTATED
                             SECURED PROMISSORY NOTE
                             -----------------------




$123,764.93                                         Date:  January 20, 2000
                                                    Amended and
                                                    Restated Date:  July 9, 2002



               FOR VALUE RECEIVED, the undersigned, Michael J. Kelly, (the
"Borrower"), hereby promises to pay to NBC Acquisition Corp., a Delaware
corporation (the "Payee"), the principal sum of One Hundred Twenty-three
Thousand Seven Hundred Sixty-Four Dollars and Ninety-three cents ($123,764.93),
together with interest on the unpaid balance of such principal amount from the
date hereof at a rate of interest equal to 5.25% per annum payable on or before
January 20, 2010.

               1. INTEREST. Payment of interest shall commence on December 31,
2000 and shall be payable thereafter annually on December 31st of each year.

               2. PAYMENTS. Payments of principal and interest of the Loan
evidenced by this Note shall be paid to the Payee at its principal office in
Lincoln, Nebraska (or where otherwise specified by the Payee), by certified or
official bank check or personal check (subject to collection) payable to the
Payee. If the date set for any payment of principal or interest on this Note is
a Saturday, Sunday or legal holiday, such payment shall be due on the next
succeeding business day.

               3. PLEDGE. The Borrower has utilized the proceeds from the Loan
to purchase from Payee the Original Shares (as defined in that certain Amended
and Restated Pledge and Security Agreement, dated as of July 9, 2002, between
the Payee and the Borrower (as amended from time to time, the "Security
Agreement")). This Note shall be secured by a pledge of the Collateral (as
defined in the Security Agreement) by the Borrower to Payee as provided in the
Security Agreement.

               4. ACCELERATION. In the event that the Borrower fails to make
complete payment of accrued principal or interest when due under the Loan
evidenced by this Note, the Payee may accelerate this Note and may, by written
notice to the Borrower, declare the entire unpaid principal amount and all such
accrued and unpaid interest therein to be immediately due and payable and,
thereupon, the unpaid principal amount and all such accrued and unpaid interest
shall become and be forthwith due and payable, without presentment, demand,
protest or further notice of any kind, all of which are expressly waived by the
Borrower.



               5. LOST OR DAMAGED NOTE. In case this Note shall become
mutilated, defaced or apparently destroyed, lost or stolen, upon the written
request of the Payee, the Borrower shall issue and execute a new Note in
exchange and substitution for the mutilated or defaced Note or in lieu of and
substitution for the Note so apparently destroyed, lost or stolen. Thereafter,
no amount shall be due and payable or owing under the mutilated, defaced or
apparently destroyed, lost or stolen Note.

               6. PREPAYMENT. The Loan evidenced by this Note may be optionally
prepaid in whole or in part (principal amount to be prepaid, plus accrued
interest thereon through the date of prepayment) at any time without penalty.
The Borrower agrees that, so long as any amount is outstanding hereunder, any
dividend or other distribution paid or payable in respect of the Collateral
shall be paid to the Company as a payment or prepayment of the Loan. The
Borrower further agrees that to the extent that any of the Collateral is sold,
the Borrower will repay a pro rata portion of the Loan equal to the principal
amount then outstanding multiplied by a fraction, (x) the numerator of which is
the number of Transferred Shares (as defined in the Security Agreement) and (y)
the denominator of which is the total number of shares of Stock (as defined in
the Security Agreement) then constituting the Collateral before giving effect to
such transaction.

               7. ASSIGNMENT. This Note may be assigned by the Payee to any of
his affiliates, members of his immediate family or trusts, partnerships or
limited liability companies established for their benefit.

               8. CONTINUING INDEBTEDNESS. This Note amends and restates that
certain Secured Promissory Note issued January 20, 2000 by the Borrower to the
Payee (the "Existing Secured Note") and shall be in substitution for and
replacement of the Existing Secured Note. The indebtedness evidenced by the
Existing Secured Note is continuing indebtedness and nothing contained herein
shall be deemed to constitute payment, settlement or a novation of the Existing
Secured Note.

               9. GOVERNING LAW. The provisions of this Note shall be governed
by and construed in accordance with the internal laws of the State of New York
without regard to the conflicts of law rules thereof.

               IN WITNESS WHEREOF, this Note has been duly executed and
delivered by Borrower on the date first above written.



                                            BORROWER


                                            /s/  Michael J. Kelly
                                            ------------------------------------
                                            Michael J. Kelly


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