It seems like the tarball for net.im/pidgin-2.6.1 was renerated on a system with intltool-0.40.6, leading to http://bugzilla.gnome.org/show_bug.cgi?id=577133 (Gentoo bug #264114). In short: if the user has LINGUAS set, then they will not get any *.mo. The fix? Add src_prepare() { intltoolize --automake --copy --force } to the ebuild. You may also want to add intltool to the deps. Setting Severity to major since loss of language files is a loss of function.
arg, forgot about this, also fixed