These ebuilds come from https://github.com/l29ah/booboo.
If you have some problems, go to the official site first.
serproxy : Serproxy is a multi-threaded proxy program for redirecting network socket connections to/from serial links, in cases where the remote end of the serial link doesn't have a TCP/IP stack (eg an embedded or microcontroller system). The proxy allows other hosts on the network to communicate with the system on the remote end of the serial link. ( http://www.lspace.nildram.co.uk/freeware.html )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a l29ah
For Paludis use this rsync : rsync://gentoo.zugaina.org/l29ah-portage
If you have a problem : ycarus(-at-)zugaina.org