MP is by far my favorite console editor, and works just fine on amd64, however amd64 wasnt even listed in the KEYWORDS. Perhas you should grep all ebuilds for x86 and insert a ~amd64, and change it to amd64 or -amd64 depending on the feedback. Just a suggestion. Other than that, my AMD64 Gentoo is awesome!
Sorry, that's not the tactic we follow (and way too much work) We're completely depending on user input via bug reports on this. You'll find more info on http://amd64.gentoo.org/technotes.xml Read the paragraph about Keyword bugs ;-) In CVS now, thanks.