There are a fair amount of foreign language options for the Sense keyboard but to my amazement there is no Japanese. There is the Google IME that can be downloaded from the Play Store and while tolerable, Sense does not make it easy to switch to it. I either have to have yet another icon in my status bar as an IME switcher or pull down settings and change it in the Language menu every other time I get a message.
There has to be something floating around that I can install, I'm sure it's in the HTC J ROM's but I don't know enough to extract it myself. If anyone can help I would really appreciate it, I love this phone and the Sense (to my surprise) but this is really killing me.