Firstly, install mercurial into /usr/share/emacs/site-lisp/mercurial/, not /usr/share/emacs/site-lisp/. That way it will conform to what all the other emacs ebuilds do. Secondly, the 70mercurial-gentoo.el site file needs fixing. Currently it calls (load "mercurial"). This is an expensive operation to do from a site wide init file especially since mercurial.el loads several other libraries. Instead, don't load it. The 70mercurial-gentoo.el should contain the following only: (add-to-list 'load-path "@SITELISP@") If it came with any autoloads, you'd add those to the site file as well, but it doesn't.
Fixed
