includes don't work, just upgraded to 4.3.1

[TravisB]

The company my site is hosted with upgraded from 4.2.1 to 4.3.1 and now my includes to other directories do not work. They have Windows 2k, IIS 5.
example:
include "content.php"; // works
include "/include/footer.php"; // does not work
I can not make changes to the php.ini file because this is a shared server. What changes do I need to make to my code to get this solved?
Thanks,
Travis

[TravisB]

I think I have figured it out.

include "/include/footer.php"; // does not work
include "include/footer.php"; // DOES work
include "../include/footer.php"; // DOES work

I just do not understand why the way I originally had it does not work. It seems like the way to access the files. You do not have to worry about it being ../ or ../../ or whatever because you can start from the webroot no matter where the page that is making the include call is located.