wierd try 2 things. 1) back up your sdcard and reformat it than put your stuff back on it.
2nd wiper everything and install rom clean from scratch meaning from the rom.zip after wiping everything.if the sdcard thing doesnt work.
did you change kernels, themes recently.
other than corrupted files i dont see what could cause this.
I know your not talking about sourcery , PE is a fine rom and should have these problems jsut start up.
sorry chizzle i know im suppose to push sourcery but that eagle guy just stopped making the rom so i dont like him anymore.