I was stationed in Japan for five years, and almost all of this is just plain untrue, unfortunately. The bits of it that are true (like it being difficult to obtain citizenship) apply not only to Muslims, but to everyone who’s not born Japanese.
http://en.wikipedia.org/wiki/Islam_in_Japan
You don’t have to look far in Tokyo to find Islamic community centers or mosques, and there are entire neighborhoods made up largely of Arab immigrants.
As for Japan being a “very evolved people,” that’s kind of a stretch, too, considering that many (their leaders especially) consider Americans to be the most backwards people on the planet and spend a lot of time protesting our military bases there (which are meant to protect them.)
Since when did we start posting stuff without even bothering to see if there’s any truth to it?