I get this when I run chkrootkit:
Checking `chkutmp'... The tty of the following user process(es) were not found
in /var/run/utmp !
! RUID PID TTY CMD
! root 2167 tty1 /usr/bin/Xorg :0 -nr -verbose -auth /var/run/gdm/auth-for-gdm-1tUOpM/database -nolisten tcp vt1
chkutmp: nothing deleted
Press ENTER to exit
Any ideas what's going on here?

