Theme crashing

[Yellow Onion]

After a while of having the desktop running, my theme crashes, and reverts to the default theme, and trying to change the theme back, opening System > Preferences > Appearances, causes X to crash.

It would be nice if some one help me track down what exactly was happening so i could either fix it or report a bug

[Kilz]

I am also having the revert to default theme issue. But it doesnt seem to be limited to Ubuntu as I have seen the issue on a friends Arch linux install.