Groupchat into Roster
The idea is to add a new JID to your roster for every groupchat bookmark.
If you join a groupchat the newly generated contact becomes "online". If you doubleclick one of those new contacts you open the corresponding chatroom. IF YOU CLOSE THE CHATROOM WINDOW the contact in your roster still remains online and you don't quit the room!!! If your nick is mentioned in the room you get a normal contact notification. If nobody said anything in the chatroom the status of the contact in your roster becomes "away" or "xa" ...