I follow Japan football. My Team - Nagano. Nagasaki beat my team for J2.
Nagasaki coach play him last year for def midfield. He name in JFL top 11 2012.
He Japan citizen, no play for NZ.
I see from our reliable friend Wikipedia that his application for Japanese citizenship was approved in May 2013. I know Japan is funny about dual citizenship... so would this in anyway negate his availability for the All Whites? Sorry my knowledge on this topic is rather limited!
Edit - seems the forum isn't quite able to handle Japanese characters.