Is it income if you can't cash the check?

[lifeisgood]

Real simple question to help you ex-tax accountants stay sharp.

I received a check late Friday afternoon on 12/29 - an interest payment on a loan. The banks were closed for the holiday weekend and there was no way of depositing the $ in 2006.

Am I supposed to declare this as income in 2006? I'm sure the guy who wrote the check declared it as an expense.