For Japanese character to work in html on the web, copy your Japanese characters from NJstar and paste them into an entity encoder.
An entity is something from the ASCII table which is an international standard for characters/symbols/numbers etc.
An entity looks something like this &*#*12527, but without the asterices(*), if i would leave that asterice away you wouldn't see the entity code, but you would see a Japanese Katakana character.(-wa)
Try it, just type that entity into this forum without the asterices(*) and you will see that it appears as a Japanese character when you post your message.
Now if you want to convert entire strings of Japanese characters that you typed in NJstar, then you would need an entity convertor.
You can find one here:
Wide character to entity encoder
Though i suggest you save the html file of this convertor onto your hard disk, because i don't know how long this convertor will stay online.
Entity convertors are a rare thing, weird but true, you won't find many around on the web.
So good luck with it and have fun, because the Japanese language is and looks just way cool.
ワタシ
彼の握りこぶしから壊れる場合太陽は燃える