I am having the following problem; Keyboard and mouse work fine on boot up, but if I unplug the keyboard and plug it back it, the keyboard is not recognized and a hard reboot must occur. With the mouse I must exit X and restart for the mouse to become active again. A simliar problem occurs with the printer if it is shut off and turned back on again, it is not recognized. Seems to be an error re-detecting devices once they have been unplugged and plugged back in. On a side note, I think this might be related to the problem of printer ports not being detected (bug #5540)
Some machines simply do not like this. This isn't a Linux problem; I've plugged and unplugged keyboards and mice with no problem, though I do it sparingly because I've been told that it can damage some hardware if you get unlucky. Perhaps you got unlucky? I also turn my printer on and off and on and off. This is not related to bug 5540.
I had this problem with "intelligent" devices, once I went back to a simple mouse and keyboard, no more problems. I use a switch box on the system and switch to/fro all the time now without problem. (Gateway2000 Anykey keyboard and AOpen serial mouse). B