postgresql support in mediawiki 1.7.1 ebuild needs tsearch2 extension for work, but gentoo ebuild for postgresql doesn't implements it
We don't support postgresql in mediawiki ebuilds... Asssigning as feature request to postgresql folks.
postgresql-8.1.4 has tsearch2 support enabled per default.
postgresql-8.1* has tsearch2 support (and it works with mediawiki :)