The past three releases of Ubuntu Linux have included unreleased ATI Catalyst drivers. It started with Ubuntu 8.10, which got an early-access driver as the official Catalyst Linux driver that was available to the public at the time had not supported X Server 1.5. With Ubuntu 9.04, AMD was running behind at supporting X Server 1.6 as found in the Jaunty Jackalope, so it too received an early ATI driver. Ubuntu 9.10 also received an early Catalyst for Linux driver more than a month in advance to provide compatibility with the Linux 2.6.31 kernel. It looks like this will happen a fourth time with Ubuntu 10.04 LTS "Lucid Lynx"