I noticed the other day that when I try to start X on my i386 3.0_BETA 
machine without a keyboard plugged in, it reboots. There are no error 
messages in either XFree86.0.log or on stdout/stderr.

Having a serial console appears to be sufficient to get it to work. As you 
can imagine this makes it difficult to debug. Is this is known problem?

-- 
Stephen