This is a complete package. You do not need a retail copy of UT3 to host games. You will need to set up a gamespy login, however.
To install, set the downloaded file to be executable (chmod a+x UT3-linux-server-12172007.bin), and run it like a program; it will unpack itself.
Bugs and reports go here.
Discussion can go to the mailing list. Send a blank email to email@example.com to get on the list.
Please try to keep bug reports to Bugzilla, so the list can focus on configuration issues, questions, etc.
Still no additional word on the client; at last report, it was being held up by the replacement of middleware. UT3 is a single player and multiplayer first-person shooter developed by Epic Games which has already shipped for Windows.
Download: [ icculus.org ]