I am having some problem with the X11 lately on my Mac OSX (Leopard). I have not found a solution yet — when I do I’ll sure put it up here. But a stuck X11 window in the dock caused it to freeze up. Along with that all the fancy cover switch and other related stuff are also gone! Luckily the spotlight accepted the Command+spacebar combination and let me find terminal.app from there.
However, although I knew who the culprit was (using htop) but I cannot kill it (kill -9 kills it, but it revives!). But the following command did the trick:
It’ll kill the Dock application and then restart it instantly. (Although it did not kill the culprit, x11).
I’m yet to find a solution for the x11 problem!