gnome-panel gets stuck if the X server is killed from under it.
It seems like SIGPIPE has been set to SIG_IGN and so it doesn't die appropriately.
The stack trace looks bogus, but it could be there is some atexit handler doing
bad things or something.
So alex, kevin, and I looked at this today. It turns out there is an atexit
handler setup by ORBit to do shutdown. This results in panel_applet_frame
noticing its connection with the applet died and trying to pop up a dialog
asking if we'd like to reload the applet. Popping up the dialog results in an X
round trip (because somewhere in the stack we call gdk_x11_get_server_time) and
this makes us spin.
This still happens (to me) on FC6-Test2, fully updated to rawhide as of 2006-8-13.
gnome-panel has been crashing a lot lately, and each time it does I have to
Ctrl-Alt-Bkspace to get back at login screen and re-login. But then the gnome
panel wouldn't start claiming another instance is running. I have to drop to
tty1 and kill the defunct gnome-panel there before I could proceed.