The Ubuntu project has published a release candidate, or final testing version, for the upcoming 9.04 version of its popular Linux distribution.

"We consider this release candidate to be complete, stable and suitable for testing by any user," Ubuntu developer Steve Langasek said late Thursday in an e-mail.

When release candidates prove stable, they sometimes end up being final production versions, although Ubuntu 9.04 still has a small number of bugs to be fixed. The software, nicknamed Jaunty Jackalope, can be downloaded from Ubuntu's site.

For this release, the project has focused on faster boot speeds and a new desktop notification system. The server version of Ubuntu 9.04 has focused on integration with cloud computing (for example, integration with Amazon.com services) and a more integrated mail server stack based on the postfix and packages.

The 9.04 release of Ubuntu also integrates the Netbook Remix software, which makes Ubuntu easier to use on the popular low-powered laptops that have come to be known as Netbooks. Ubuntu 9.04 is known to work on Asus' Eee PC 900, Acer's Aspire One, and Dell's Mini 9 devices.

Ubuntu 9.04 is scheduled to be released on April 23 and will be supported for 18 months.