debug X errors?

[Luis Villa <luis tieguy org>]

Hey, guys-
The latest stuff is looking pretty nice, but unfortunately it is also
crashing pretty regularly for me, with errors like the following:

Bug in window manager: Unexpected X error: BadDrawable (invalid Pixmap
or Window parameter) serial 26638 error_code 9 request_code 136
minor_code 4)
Shell killed with signal 6

Any pointers on how to debug those? Also, is there any way to
automatically restart shell instead of falling back to metacity when
this kind of thing happens?

(jhbuilt yesterday from scratch; intel 945GME video; Fedora 13.)

Thanks-
Luis