Autogroup by ID is not working on existing windows or newly created windows from an existing application.

The problem was experienced while trying to setup an autogroup with Skype and Pidgin. Pidgin works just fine, however, Skype, because it loads up with an initial window usually used for login, then closes that while spawning the userlist window, it does not get the autogroup rule applied, however it gets other rules, like positioning/size rules.