These ebuilds come from http://overlays.gentoo.org/dev/jokey.
If you have some problems, go to the official site first.
virtualbox-bin : Family of powerful x86 virtualization products for enterprise as well as home use ( http://www.virtualbox.org/ )
virtualbox-guest-additions : VirtualBox kernel modules and user-space tools for Linux guests ( http://www.virtualbox.org/ )
virtualbox-modules : Kernel Modules for Virtualbox ( http://www.virtualbox.org/ )
virtualbox-ose : Softwarefamily of powerful x86 virtualization ( http://www.virtualbox.org/ )
virtualbox-ose-additions : Guest additions for VirtualBox ( http://www.virtualbox.org/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a zugaina
For Paludis use this rsync : rsync://gentoo.zugaina.org/zugaina-portage
If you have a problem : ycarus(-at-)zugaina.org