'--with-unicode' configure option was added for metalog to properly utf8 input in the logs, but the ebuild doesn't use it. At this time, it doesn't do much, just changes which chars are treated as control chars.
now in the tree; thanks for the report http://sources.gentoo.org/app-admin/metalog/metalog-1.ebuild?r1=1.2&r2=1.3