my thinkpad t40 experiences

[Rahul Siddharthan]

About suspend: I couldn't get it to work on my old laptop (a Compaq),
either with linux or with FreeBSD, but standby (apm -Z in FreeBSD, apm
-S in linux) worked fine provided I switched to a virtual console
(ctrl-alt-f1) first.  This was good enough for me but it's probably
not good enough if you plan to keep your laptop that way for several
hours without AC power.

On my new laptop, there's no APM bios, only ACPI, so FreeBSD 4.x won't
support any power management.  FreeBSD 5.x doesn't work right (with
ACPI disabled it doesn't boot fully, and with ACPI enabled it doesn't
find the touchpad).  You may have better luck though.  It may be worth
trying ACPI, I think many newer laptops don't have very functional APM
BIOS's. 

With linux, I'm using the "software suspend" patch and it works fine
for me so far; you may want to try it, after reading all the warnings.
  http://fchabaud.free.fr/English/default.php3?COUNT=3&FILE0=Tricks&FILE1=Laptop&FILE2=Swsusp 
I'm using the version for kernel 2.4.20 with acpi patches (from
http://acpi.sf.net); there are more recent acpi patches for more recent
kernels, you can find an "all-in-one" kernel with both the acpi
patches and swsusp (I haven't tried it) at
  http://savannah.nongnu.org/projects/laptopkernel/

Rahul