IMERJ version 0.9 has been released (3/9/2013, although it was finished 4/24/2010). This is a a "poor man's" Japanese input method editor, which allows you to enter Japanese kana by typing romanized text in the edit window. It is intended primarily for use on non-Japanese systems where a proper IME is not available. Input is kana only - kanji conversion is not supported. Thanks to Alex Taylor for the info.
Source: OS/2 Warp News and Rumors