I upgraded all packages to the latest version in a vanilla (only changed variable was efs-program-name to make it work at all) XEmacs 21.1 on RedHat 7.2 today, which went fine, but when I tried to quit XEmacs I got this: Signaling: (error "invalid lazy-loaded byte code" nil) fast-lock-save-caches-before-kill-emacs() kill-emacs() save-buffers-kill-emacs(nil) call-interactively(save-buffers-kill-emacs) I'm not sure if it is related, but ps auxww|grep xemacs printed: root 2619 1.2 3.4 17900 13368 pts/2 S 14:05 0:28 xemacs -u root root 2621 0.0 0.2 3728 976 ? S 14:05 0:00 /usr/lib/xemacs-21.1.14/i386-redhat-linux/wakeup 300 I'm not sure what the last thing is. I can't reproduce it.