9.1: keyboard input partially broken

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

I've installed 9.1 on a machine at work.  The goal is to run a turnkey
product which among other things uses X for displaying output and, to
some extent, taking input (specifically, keyboard events).

This worked under 5.2 and 8.0.  But, under 9.1, I find that keyboard
input is *almost* completely nonworking, under certain circumstances.

It's not just the application, either; if I start X with nothing but
the server and an xterm, input into the xterm is similarly broken,
under those circumstances.

Specifically:

Upon reboot, the wscons console seems to work fine: I can log in, run
text-based commands, etc, and it is all good.  I can even start X

xinit /home/mouse/X/x-client -- /usr/X11R7/bin/X -retro -tst -depth 8 -cc 3

and it all works apparently normally.

But, if I leave the console at the login prompt, ssh in from my main
desktop, and run xinit (the same way), the X server comes up but
keyboard input doesn't work.  I've occasionally had a few events get
through, but only a very few; for example, I've sometimes had a key
start autorepeating, as if the key-down got through but nothing after
that did.  This happens only for events within a short, but still
human-perceptible, time after starting - a second or two at most.

If I log in on the console and then start X from the ssh session, it
still fails, even if the ssh session is run by the same user who logged
in on the console.  Even if the console is at the login prompt and I
run xinit as root.

This might or might not be a problem for the production system - it
runs from a minimal system, with the application as /sbin/init, which
forks and execs the X server - but that is untested as yet, and in any
case this severely cripples development.  Hence, my question: how do I
fix it?  What's needed to make the X server to take keyboard events
normally even if the server is started from other than a console login?

I had a look at Xorg.0.log, but I don't see anything promising there.
I can quote any desired portions of it if anyone wants, but it's over
250 lines, so I hesitate to just include the whole thing.

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