how to teach ACPI not to mask FN+F12 key on thinkpad ?

[KubaTyszko]

hi.
for a few days i have tried various things with suspend/resume and my
thinkpad t42.
first of all
i have prepared bootable cd with ibm tool that creates STD partition or
a file in fat partition (recommended by ibm, but from my observations
there is no difference between partition and file on fat).
STD works with freebsd with acpi disabled.
with acpi enabled whtn i press FN+F12 nothing happens.
can i make acpi to send fn+f12 to bios (or wherever needed). ?
if i could make this happen i would finally have working and long
lasting suspend (my model drains battery in 12=16 hours when STR).
cheers