WordPress MU

I have mu installed on windows 2003 with iis i went through the index-install.php process and there were no issues. however when i try to log in i get redirected to the login page, with no error shown.
so is this a mod_rewrte()issue?
can isapiRewrite be used instead of mod_rewrite?
what are the rules that are used?

mod_rewrite rules are used, but I'm not sure if an IIS module will work. Look in the file .htaccess in your install directory.

Take a look at

http://mu.wordpress.org/forums/topic.php?id=5483

and

http://mu.wordpress.org/forums/topic.php?id=6208