A more recent version of cvs2svn has been available for a few weeks, and creating a new ebuild for it was trivial, so here it is. :) Please find attached.
Created attachment 151096 [details] Ebuild for 2.1.1 of cvs2svn. Adapted from the 2.1.0 version of the ebuild that's already in portage.
Thanks. I had to make some changes to your ebuild. But it's committed.