Not many free programs allow this conversion... There might be something out there, but I'm not sure right off. Now TMEPG converts AVI to mpg videos, and stokevideo converter(I think that's the name, I can check when I get home) allows from just about any format to any codec of AVI and WMV's... I know this isn't what you need, but maybe it'll help
Desktop: Athlon 64 3700, 1024M RAM, GF 6200 TC 256M, 2x 80G, 2x DVD-RW
Laptop: Sempron 2800, 512M RAM, Unichrome, 60G, DVD-RW
Macintosh:G4 1.33GHz, 512M RAM, Radeon 9200 32M, 40G, DVD/CDRW
They get me from 0 to 1...