The x264 library (x264-svn) is added to portage to be used with Cinelerra-cvs. So it can be added to VLC too. Reproducible: Always Steps to Reproduce:
It's currently -*, so I won't add it (also because I have to try it on amd64 first). Also, I'd rather wait for something better than an SVN snapshot. Please note that x264 is needed only for encoding, ffmpeg takes care of decoding.