Comment 2 for bug 236210

Well, I had to update the helper script, as it seems a complete X restart is really needed (not so helpful if multiple users are using the GUI, but okay if only 1 at a time):

$ cat /usr/local/bin/kill-stragglers
#!/bin/bash

# takes 1 argument: the username of the user who logged off

USER=$1
sudo kill -9 $( ps U $USER | grep -v TTY | awk '{print $1}' ) 2> /dev/null
sudo /etc/init.d/gdm restart