I fixed or added ebuild files for Gentoo Prefix/MacOSX. these were tested in MacOSX Lion.
Note: I do not still make sure of installing in Mountain Lion.
- open ${EPREFIX}/etc/layman/layman.cfg
- add URL in a item "overlays" overlays : http://www.gentoo.org/proj/en/overlays/repositories.xml http://github.com/nana4gonta/gentoo-prefix-overlay/raw/master/repository.xml
- enter the command layman -a naota-prefix