laptop reboots right after hibernation

[Tomas Carnecky <tom@dbservice.com>]

echo disk > /sys/power/state

successfully saves that state to the disk, but just as the laptop is
about to turn itself off, it reboots (successfully, so the
hibernation/resume process works well, even with X running! which is
awesome :) ). But I'd rather like the computer turned off after I
hibernate it. Where could the problem be?

It's a new laptop, TP X61 tablet, I tried ubuntu (7.10, gutsy) for a few
days, both suspend and hibernate worked there (with one or two crashes,
probably due to X, I've read that the intel driver got some
suspend/resume improvements recently). Now I'm running gentoo, kernel
2.6.24-rc2. I'm using newer versions of almost all software now compared
to the ubuntu system.

tom