In trying to wake from sleep on my ibook, my screen freezes. I can move the pointer but it won't click on anything on the desktop, the menu or the dock. I tried re-closing the lid for a minute -- sometimes it helps, sometimes not. If not, the screen goes black, and I have to re-start. Sometimes it fully restarts, sometimes it hangs before the restart is complete. After the last freeze, my console showed about 50 copies of the following line: ibook kernel: IOHIDSystem: postEvent LLEventQueue overflow. I am running OS 10.4.3 on an ibook G3 800MHz. Anyone have any suggestions on how to deal with it?