I tried again.

I have now confirmed that whether I do it as "shutdown now", or "kill
-s TERM 1", and whether I'm logged in as root (I know, you shouldn't
log in as root :-) or whether I'm logged in as jwjr and su to root,
and whether I'm running ctwm or twm, even if I wait five minutes the
machine doesn't go to single-user mode.  X shuts down, and the system
stops responding to the keyboards, and that's it.  Should I wait
longer?

However, if I'm not running X, everything works just fine, no matter
who I'm logged in as, and no matter how I signal init.

I'm running NetBSD 1.3.2 for i386.  I have applied the patch from
NetBSD Security Advisory 1998-005, relating to mmap.  I'm using X11R6
as distributed with 1.3.2, I think.  (I haven't made any mods.)  Any
ideas what might be the source of this problem?

Regards,
James Wetterau