I've had to uninstall RC1.0 in one of my desktops, after the mail and dialup connection stopped working properly. The mail problems consisted either of freezes or seemingly baseless error messages that told me I would have to shut Mozilla down. The dialup problem seems to have been related to Mozilla's attempts to report the incidents. Even after I restarted XP, the thing tried to reconnect.
The beginning of these problems coincided with the first appearance of "MY name is Hammer. I like to rave", a message that suddenly showed up yesterday in the spot occupied by the Mozilla icon in mail. After it installed itself, it always appeared when I first opened mail, then it disappeared under the Mozilla icon. What's the story on Hammer and his silly message? I think I saw a posting about it somewhere before..
