When emacs-21 is executed, it looks for site-start.el in /usr/share/emacs/site-lisp ... however this file doesn't exist. Reproducible: Always Steps to Reproduce: 1. emerge app-editors/emacs 2. (e.g.) emerge app-emacs/ruby-mode 3. ls /usr/share/emacs/site-lisp/site-start.el [no file found] This is easily solved by making a softlink from site-gentoo.el to site-start.el
As noted in the information messages output by the ruby-mode ebuild, this is a feature, not a bug. Gentoo no longer manages site-start.el, allowing users to better customize their site configuration; you can make that soft link if you want.