I need some fancy date functions....
First, I need to know the last day of a givin month...

Then I also need to be able to determine the 1st, 2nd, 3rd, 4th, last [monday, tuesday, whatever] day of the month.
In other words, the user would select the 4th Thurday of Oct, 2003 - I need a way to know that is Thurday Oct 23, 2003.

This seems like something that would be a fairly common need - has anyone got anything like this already?

Thanks....