There's (buggy) support for building vim through cvs in the vim eclass. This should be fixed and ebuilds for builing cvs-versions of vim should be possible, specificially series 7. The alpha releases that exist are three months old by now and a lot has happened since then. They should probably be updated as well with a new alpha release supported by gentoo, but that's another bug report. Reproducible: Always Steps to Reproduce: 1. 2. 3.
I've committed a new vim7 snapshot.