Issue 166: xmonad segfaults while closing Swing (Java) based apps http://code.google.com/p/xmonad/issues/detail?id=166 Comment #3 by SpencerJanssen: I notice you use urgencyHook, meaning that this is almost certainly a duplicate of #140 and #165. There was a bug in the X11 library, here is a version that works (soon to be up on hackage): http://code.haskell.org/~sjanssen/X11-1.4.2.tar.gz Be sure to clean and recompile xmonad and XMonadContrib after upgrading, and execute 'xmonad --recompile'. Let us know if your problem persists with the updated X11. Issue attribute updates: Status: Duplicate -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings