Building Latest (8.1)

I'm trying to test a feature I see in the 8.1devel documentation.  I
figured I'd checkout a cvs working copy.  Following the doc I:

cvs -d :pserver:anoncvs@anoncvs.postgresql.org:/projects/cvsroot login

but that just hangs and eventually times out.  I looked at CVSup, but I
found no binaries for CVSup at ftp.postgresql.org, and building CVSup
seems to be a bit of a pain on Linux.  I pulled a tarball from the
"stable_snapshot" area of the ftp site, but that was just 8.0.3.

What am I doing wrong?

My main interest at this point is OUT parameters in PL/pgSQL.  I read
about this in the 8.1devel doc, so I thought I'd be able to test this
feature in the "latest" source, wherever that is.