There are two supportgroups and both moderators have to log in to their own supportgroup and when they do an indicator displays "online" at once. This login-logout procedure is an action outside the forum software and that's maybe a way to implement this. The login to a php way of notification could be attached to the forum login, a member is logging in at the forum and also to the php online-offline software else on the server with one buttoncklick. After that you can easy make an indicator in the public_topic.pl. But it's just an idea.
