A new USkaarj2k4 Mod has been released on the Beyond Unreal website. There are two versions, one for Linux and another for Windows. The new version is stable as it was tested for bugs.
Uskaarj2k4 is a real time strategy total conversion for UT2004 that alters everything in standard UT2k4 into a real time strategy game like C&C Generals or Starcraft. It consists of a base-building, resource collection and controlling units on a battlefield.
For more info, click here.