I am running Gentoo for AMD64 and trying to play videos that use Windows codecs. I have the "win32codecs" USE flag in make.conf and have emerged "mplayer-bin" (the 32-bin binary version of MPlayer for compatibility "win32codecs"). MPlayer expects the codecs to be in /usr/lib/win32 and since I am running a 64-bit system, the lib dir points to lib64. I believe the codec directory settings are set at compile so there is no way to change the directory without compiling 32-bit MPlayer and not using the emerge binaries. That wouldn't be the worst things in the world, but I don't want to do it if it is not necessary. Nor do I want to put the 32-bit codecs in the lib64 directory. Any ideas?

If you compile MPlayer from scratch, I think you will get more features. Refer to my install:
http://www.flyzhy.org/projects/MplayerInstall.html
and hope to help.

Thanks for the link to your site I think I'll just recompile it.