The latest version of media-libs/libsdl in prefix-tree is media-libs/libsdl-1.2.15-r2, but there are ebuilds in gx86 that depend on >=media-libs/libsdl-1.2.15-r4, causing installation of those packages to break unless the offending package versions are manually masked.
Needs some work on darwin to be bummped.
we're on gx86 version now