Issue when sending a SIGKILL to X while on the current display

Hello x11@,

How to reproduce
1- launch a WM, let's say, fvwm
2- spawn a terminal
3- find the pid for /usr/X11R6/bin/X (ps -x ..)
4- execute kill from the spawned terminal with the -KILL switch and
the pid of X

CTR+ALT+F* keys won't work after that and the user is stuck with
a static display. The only thing to do then, is to shutdown by hand.

Tested on a current system (OpenBSD 4.8 GENERIC.MP#296 i386), 
with the default configuration, that is with startx using
/etc/X11/xinit/xinitrc.

Although killing X this way is not a good practice, I think this deserve
a fix.

bye,

benjamin