Define "jittery". Are the shadows aliased, or "blocky", or both?? Aliasing can be alleviated (without too great of a performance hit) with hardware filtering (Nvidia via pcf, ATI via fetch4) -- and there are better techniques out there that can yield even better results (but bigger performance hits). Blocky maps are probably due to low resolution shadow maps. Anyhoo, not to sound condescending, but if you need some advice, I could help. Just gimme a holler.