It's just a matter of building a small cache. Insert a timestamp and user ID when the user accesses the site, and expire the entry a few minutes later (15 minutes on PM if I'm not mistaken). Throwing something like Cache::FileCache at the problem makes it easy as pie. The only question, and you haven't mentioned anything about that, is how do you identify your users? PM tracks a cookie set by the script at login.

Identification is the harder part. Your question whether you can use Win32::NetAdmin suggests you have made no provision for that. You're out of luck there - HTTP has nothing to do with Windows Networking.

Makeshifts last the longest.