Today I was using Emacs and used File->"New Frame on Display..." to put an emacs frame (a window) onto localhost:10 which was forwarded off over ssh to another display. Oddly, with this machine combination that I've not tried before, keyboard input wasn't recognised by Emacs and while using the mouse to try to see what the problem was, the connection was lost with some BadWindow message displayed on the original Emacs frame's minibuffer (vanished before I could copy it). I'm using Emacs 21.3, OpenSSH 4.0p1 and x.org 6.8.1 - has anyone seen similar problems or know what causes them?

(By the way, if you've never used "New Frame on Display..." or its predecessors to create collaborative editing sessions, you've been missing out on a useful tool. Give it a go!)

Thanks in advance for any clue,