keyboard not recognized with 2.5 kernels

[Matt Pharr <matt@pharr.org>]

(I've had this problem with both 2.5.39 and 2.5.45; haven't tried any other
versions.)

After 2.5 boots, my keyboard doesn't seem to be recognized (it's an
old-style one plugged into the keyboard port, not a USB keyboard).
Everything is fine up to the login: prompt, but then any key I hit doesn't
cause anything to happen (including ctrl-alt-del).

I have tried booting with "i8042_direct=1" on the kernel command line (as
suggested in another thread about other keyboard problems), and that didn't
help, and I have tried plugging in a plain old Dell keyboard instead of the
Logitech iTouch I've got plugged in now.  Neither of those helped.  I also
tried building without SMP support, and that didn't change the situation
either.

This is on a home-built machine, Asus A7M266-D motherboard, dual athlon
1900MPs, etc.

I don't think I did anything dumb in the configuration step--I used my
working 2.4.19 .config file, did a 'make oldconfig', and answered questions
in conservative ways.  In particular, I do have CONFIG_INPUT_KEYBOARD set
properly:

#
# Input Device Drivers
#
CONFIG_INPUT_KEYBOARD=y
CONFIG_INPUT_MOUSE=y
# CONFIG_MOUSE_INPORT is not set
# CONFIG_MOUSE_LOGIBM is not set
# CONFIG_MOUSE_PC110PAD is not set
# CONFIG_INPUT_JOYSTICK is not set
# CONFIG_INPUT_TOUCHSCREEN is not set
CONFIG_INPUT_MISC=y
CONFIG_INPUT_PCSPKR=y
# CONFIG_INPUT_UINPUT is not set

Any thoughts about how to debug further?  I fear that I've forgotten
something obvious, but can't think of anything else to try.

thanks,
-matt