To add this overlay to a Gentoo system, run the following command: layman -o https://raw.github.com/gmt/xattr-overlay/master/overlay.xml -f -a xattr but!!! don't do it. Upstream now has all of this functionality merged in and it is almost certainly best to use their versions -- not only will you benefit from being on the same code-base as upstream, but any subsequent enhancements or bugfixes I might contribute myself will be there -- not here. Hooray, one less fork to maintain! -gmt