Created attachment 24388 [details]
Seems to dynamic ligthing effect is broken in Mesa-7.4 for r200 (at least i only tried on 9250 card), it was working for many years (Mesa-7.3<=). There are screenshots from Doom 3 and RTCW, but it can be also easely noticed in every quake3 based games with that effect turned on.
Created attachment 24389 [details]
Was reported as fixed in bug #20966.