For the longest time I avoided using ACPI for power management on my Thinkpad X31 (instead I stuck with APM) because I could never get all the little hacks lined up properly. ACPI, since it is done primarily in hardware, requires a lot of tricks to get your machine to suspend and resume properly. Switching out of X, turning off LCD backlights, resetting graphics cards, etc etc. Its a real hassle.
However, if you’re fortunate enough to be running Debian Linux, you can install the “hibernate” package. Hibernate is basically sophisticated Bash script with pluggable options for all the most common ACPI hacks. I had ACPI up and running within minutes.
If you’ve got a Thinkpad X31 or similar machine, feel free to download my hibernate.conf and tweak it to your purposes. The only additions beyond a fairly standard hibernate configuration I had to make were adding hooks to turn the Radeon backlight on and off.