I've /bin/bash-ed my way through all the s2ram options in the opensuse link - but sadly none have resulted in a successful resume.
I'm now using LXDE. Another change to my system - I have installed a new video card (nvidia GeForce 8400GS) to solve a problem of occasional boot failures (which it did).
The resume behaviour is now different. It now all sounds much more hopeful (no CD drive clunking), but all I get is a static cursor at the top left of the screen.
This is the same display I get briefly before the nvidia logo appears during normal boot - so I'm wondering if the break point is perhaps trying to restart the video card?
If anyone has any other suggestions on how to get suspend/resume working I'd be pleased to hear them.