[CentOS] Suspend and/or Hibernate

I asked about ACPI several weeks ago but received no responses. Are suspend and hibernate features not supported in CentOS yet? I noticed there is a daemon for acpi:

[scarolan@kalki ~]$ chkconfig --list | grep acpi acpid 0:off 1:off 2:off 3:on 4:on 5:on 6:off

But how do I use this feature? Normally I'm accustomed to this being a menu option when I log out (eg, on recent versions of Fedora or Ubuntu). I noticed in /etc/acpi/events/ there is a file called sample.conf which configures the power button to attempt a graceful shutdown. How can I add a 'suspend' or 'hibernate' feature and bind it to a keyboard combination?

thanks

Sean