I dont think this is the answer you are looking for but, on my Thinkpad T40, I had to set the suspend on the lid being closed. System/ Preferences/ Power Management. then select
suspend or hibernate when lid is closed. your is probably differnet since Im running Ubuntu 7.1. the suspend or hibernate did not work till I set them under power management.
I dont know if it is the suspend to ram that you are talking about, but it seems to work on mine.