When I log in a guest, and choose a nick that was previously used already (even several days later, and several reboots of the client PC), I get the "this nick is already in use" prompt. If I click OK without changing that nick, I am correctly logged in, but I get a "you must be connected to post" message, although the icon shows the "connected status". But I CAN post, under the "already used" nickname.
So anyone can join and "steal" someones nick.....
Dirk