Don't wake screensaver on mouse movement

[igitur]

Hi,

This is probably the reverse of what most users want.

I don't want my screensaver to wake when I move my mouse. How can I set this?

Why do I want this? I have Pidgin installed and set it to go offline (not only away) when the screensaver activates. For some reason, my mouse often picks up movement (ghosts?) and then the screensaver wakes up and Pidgin goes online. My IM contacts think I'm online and start chatting to me. Some get annoyed that I don't respond! I'm not disciplined enough to unplug my mouse when I go to sleep.

[ubunterooster]

set the screen to lock when the screensaver comes on. The best I can come up with