Comment 30 for bug 624877

WARNING: those previous commands are for LUCID, and involve installing packages from NATTY. Buyer beware! Furthermore, if it's run on a non-LUCID system it will result in NATTY packages being installed by DEFAULT unless the Pin-Priority setting is changed from LUCID to whatever the system is actually running.

To downgrade after upgrading: rm /etc/dpkg/dpkg.cfg.d/force-unsafe-io; aptitude -y install dpkg/lucid

To undo repository/apt changes after downgrading: rm /etc/apt/preferences.d/prefsources /etc/apt/sources.list.d/natty.list /etc/apt/apt.conf.d/98cache-limit