The current value of the HOMEPAGE attribute in the cvs ebuilds points to http://www.cvshome.org/ which redirects to http://ximbiot.com/cvs/cvshome/ where you can read that this page is no longer maintained. So I suggest to change the HOMEPAGE of the CVS ebuild to either http://ximbiot.com/cvs/wiki/ (suggested by above page) or http://www.nongnu.org/cvs/ (if you prefer not to link to a wiki).
Fixed with cvs-1.12.12-r3.