avahi : System which facilitates service discovery on a local network (meta package) ( http://avahi.org/ )
avahi-base : System which facilitates service discovery on a local network (base pkg) ( http://avahi.org/ )
avahi-gtk : System which facilitates service discovery on a local network (gtk pkg) ( http://avahi.org/ )
avahi-gtk3 : System which facilitates service discovery on a local network (gtk3 pkg) ( http://avahi.org/ )
avahi-mono : System which facilitates service discovery on a local network (mono pkg) ( http://avahi.org/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a sabayon-distro
For Paludis use this rsync : rsync://gentoo.zugaina.org/sabayon-distro-portage
If you have a problem : ycarus(-at-)zugaina.org