using ubuntu karmic (9.10) and reporting the keyboard mapping issue too.
Keyboard is a french one on both machines. Distant computer is running winxp.
On the local host, keyboard is mapped french as long as I'm not typing my password
in the "unlock session" screen on winxp.
Seems that the plugin maps the keyboard only to english (ie qwerty).
obviously, tried to deactivate plugin (without restarting firefox nor exiting remote control
window) and keyboard mapping comes back to azerty on the remote computer.
Hope this can help ;-)