And bitcoin client also are not translated to Japanise!
Japan has the world's tenth-largest population, with over 127 million people.
A major economic power, Japan has the world's second-largest economy by nominal GDP and the third largest in purchasing power parity. It is also the world's fourth largest exporter and fifth largest importer.
(and we still trading Japanese yen )
It's not in Bengali or Urdu either, both of which have more native speakers in the world than Japanese...
http://en.wikipedia.org/wiki/List_of_languages_by_number_of_native_speakers
...while several languages are represented that don't even come close.