All maps are pretty much worthless as Japanese government restricts the export and use of its geo-information. All maps suck there except OSM maps which are created by Japanese citizens. So, to be fair to Apple, and Google, and Nokia/Navteq, they all lack. Why, do you live in Japan? Is that why it keeps you from updating your iPhone. If you do live in Japan, you do realize that Google Maps in Japan is also not too good either for same reason.