Comment 9 for bug 695648

--disable-encoder=aac is only set on ia64. You can check that by looking at
debian/confflags in the FFmpeg source package or on git [1,2].

[1]
http://git.debian.org/?p=pkg-multimedia/ffmpeg.git;a=shortlog;h=refs/heads/ubuntu
[2]
http://git.debian.org/?p=pkg-multimedia/ffmpeg.git;a=blob;f=debian/confflags;h=da57f23aa2d3330b436121eb37a481b544928099;hb=012f3392c047e6917b9908b35b17623d0ec546c7