Can COUNTIF use a cell as a criteria reference?

From: SteveP (SteveP_at_discussions.microsoft.com)
Date: 08/04/04 

Date: Wed, 4 Aug 2004 10:27:04 -0700

=COUNTIF(B2:B6,"<D2")

This formula always returns the result "0". The cells are formatted as
dates. If I convert the range to numbers, and insert a number as the
criteria, I get the correct result.

1. Why can't I use a reference as criteria?

2. Why can' I perform the calculation on dates?

Thanks,

Steve Pretti