These ebuilds come from http://git.goodpoint.de/?p=overlay-sping.git;a=summary.
If you have some problems, go to the official site first.
redirfs : The RedirFS or redirecting file system is a new layer between virtual file system switch (VFS) and file system drivers. ( http://www.redirfs.org )
zfs : Native ZFS for Linux ( http://wiki.github.com/behlendorf/zfs/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a sping
For Paludis use this rsync : rsync://gentoo.zugaina.org/sping-portage
If you have a problem : ycarus(-at-)zugaina.org