Auto power-off w/o APM/ACPI?

[Jeff <b3ak3r%lavabit.com@localhost>]

I've got an older Thinkpad (T23) running a 4.0 snapshot from 2/9/08. I
upgraded from the 4.0 formal release to get better uhub support for my
Dock II docking station. The USB hub on the docking station now gets
probed and configured however I'm no longer able to have APM enabled in
the kernel; doing so prevents probing of the forementioned hub. Enabling
ACPI allows the hub to be probed too but it causes other problems,
including disabling the screen blanking button so I've opted not to use
it. The main issue I have with not having APM enabled is the inability
to pass the "-p" option to 'shutdown' - mainly a problem when I want the 
system to turn off after running a lengthy process overnight. Is there 
some way to achieve the auto power-off w/o APM/ACPI?

Jeff