include_path in windows

I am trying to get my php.ini file configured correctly. I have a script that calls the require function/command( I'm not sure which it is..) Here's what the .ini file is: include_path=d:\sites;d:\sites\merchantpower\setup According to the notation in the .ini file I have the correct syntax, but it never seems to look in the second path. Can someone explain this to me better. Remember I'm dealing with Windows to do development. I would think that the script would start to look in the d:\sites directory and then go to any sub directory from there... TIA, -Shane