The latest xorg update was a big regression for me on a dual display setup.
Is there a simple way to revert to the previous version?
I'm on Lucid Lynx.
Please write a comprehensive bug report against the xorg package on launchpad. Updates should never break things. If it happens, it's important to notify developers, so they can fix it. (Even if you suspect they will not fix it because it may be an edge case, I does not harm to report the bug.)
Apt does not support reverting an action once completed. And Ubuntu/Apt does not (officially) support downgrades.
Ubuntu can get packages (updates) from different repositories. In synaptic (or other apt front ends), you will see that different version of xorg related packages from different repositories are available. Using the "Package" -> "Force Version" menu, you can request the downgrade. (The original verison that shipped with lucid comes from the repository "lucid" given in parentheses. The offending upgrade probably came from lucid-updates.)
Downgrading one xorg related package will trigger downgrades of several other xorg related packages. It may take some tries before synaptic gets it right.
TL;DR: Use Synaptic to downgrade xserver-xorg-core to the version from lucid. Solve potential dependency problems until all xorg related packages are downgraded.
