freeradius : Highly configurable free RADIUS server ( http://www.freeradius.org/ )
openl2tp : Userspace tools for kernel L2TP implementation ( http://www.openl2tp.org/ )
ppp : Point-to-Point Protocol (PPP) ( http://www.samba.org/ppp )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a srcshelton
For Paludis use this rsync : rsync://gentoo.zugaina.org/srcshelton-portage
If you have a problem : ycarus(-at-)zugaina.org