Matthew,
how should I set system locale to ja when I execute fresh-dev-env-from-scrach.This is kind of messy to do. A dev-env is nothing more than Socialtext running with the test fixtures, and the code to set that all up is messy and complicated. The best I can do ATM, to ensure Ja is the locale used from the start, is to apply the patch below. This could probably be automated somewhat, but it's not clearl how due to various complicated things. Tell me if this works for you.
It works! Best Regards, Takatoshi Kitano