But after I've loged out, the X server has been restarted:
1064 ?        Ssl    0:01 gdm-binary
 5540 ?        Sl     0:00  \_ /usr/lib/gdm/gdm-simple-slave --display-id /org/gnome/DisplayManager/Display1
 5542 tty8     Ss+    0:00      \_ /usr/bin/Xorg :0 -br -verbose -auth /var/run/gdm/auth-for-gdm-harX5R/database -nolisten tcp
 5565 ?        Ssl    0:00      \_ /usr/bin/gnome-session --session gdm --autostart=/usr/share/gdm/autostart/LoginWindow/
 5571 ?        Sl     0:00      |   \_ /usr/lib/gnome-settings-daemon/gnome-settings-daemon
 5590 ?        Sl     0:00      |   \_ metacity
 5603 ?        Sl     0:00      |   \_ /usr/lib/gdm/gdm-simple-greeter
 5613 ?        S      0:00      \_ /usr/lib/gdm/gdm-session-worker

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