Marijn Kentie has written a Direct3D 10 renderer for the Unreal Engine, it's compatible with Unreal, Unreal Tournament, Deus Ex and Rune. The first release of this DX10 renderer was released over a year ago, and the software is being updated continuously to fix bugs and add new features.
This Direct3D 10 renderer for Unreal, Unreal Tournament, Deus Ex and Rune aims to provide a good, consistent looking and future proof renderer for these games. The focus is not on fancy effects; the idea is to have something that will allow these games to perform well and look good on modern systems, something which I can support and bugfix.
Written from scratch, it ditches a lot of legacy stuff and profits from the fact that D3D10 support means a clear baseline.
Furthermore, source code and documentation are provided (see page 2), which should aid future efforts to keep these games running.