I have discussed the matter with David Airlie, who maintains the xorg ati driver. He told me that Ubuntu have added quite a number of patches to the ati driver, and it isn't a straightforward matter - for someone who is not familiar with the X code at least (ie. myself) - to find a patch in the x.org git tree and apply it to the Ubuntu version of the driver.
I did have a look at both codebases, and I really was way out of my depth. The short story is that I upgraded to 'Edgy' where the issue has been fixed, much as I would have preferred a "safe and stable" release on my main machine. This bug is very serious, and I strongly suggest upgrading its severity. -- system freeze when using ati radeon 7000 with xorg "ati" driver https://launchpad.net/bugs/16873 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
