I am running Ubuntu Jaunty with a ATI 4850 in big desktop mode (done using amdcccle). ATI driver version 9.6

The problem is that every time my display goes to sleep, the card crashes. I can still ssh into the box but X is dead. So the screen does not wake up and I have to reboot.

There is nothing interesting syslog or kern.log, Xorg.0.log or .xsession-errors.

This is very annoying. Any ideas?

Some of the possibly relevant errors:
kern.log
[fglrx] DRM MCIL: MCIL_QuerySystemInfo command :4 not implement