Good Drupal shops in Tokyo?

Hello Drupal Japan :)

I was wondering if you know or belong to a Drupal agency in Tokyo with experience in multi-domain, multilingual pages with lots of users? My company might be looking for someone to help us grow our current Drupal site into a community, which would probably include some refactoring of what we already have and writing some modules. We had some quotes from developers, but none of them really had Drupal background, and we would appreciate somebody who knows the system. We are currently running on 5.x.

Thanks :)