Solution to patented shadows

[K.I.L.E.R]

Doom III Menu
|
 --Options
   |  
    --Graphics 
      |
       --Advanced

            [x] Use Z-fail shadows  (please uncheck this if  
                   you are playing Doom III in USA or Japan)

http://gamedev.net/community/forums/topic.asp?topic_id=181647&PageSize=25&WhichPage=2