on my new imac G5 the menu bar in the upper right hand corner where spotlight resides constantly freezes, it won't do anything, and as far as i know there is no way to force quit spotlight or the menu bar. also when this happens i am unable to log out or shutdown by conventional means, i have to either hold the powerbutton for about 6 seconds or completely unplug the machine.....anyone have any suggestions on how to fix this?