Despite the fact that VIM's webpage proclaims availability of vim 6.1, it remains unavailable, and until that time, 6.0.x will have to do. Please mask 6.1 and update the 6.0.x ebuild to reflect the latest available patchset.
It is to be found at vim.sf.net For some reason ftp.us.vim.org does not have it, but ftp.vim.org does.