I've been wondering about this for, like, 6 years. The kanji he uses for his name seem way too perfect and pretentious to be true. I mean 神威 楽斗? Really? But anyway I sort of gave up on the subject but now I got curious again. It's funny, really. English Wikipedia doesn't say anything on the subject but the Japanese one clearly states the birth name. I talked to Shinoka about it and she confirmed it. It's so starange. I mean 岡部学 is a nice name, really but by now it's hard to associate it with this giant of a man.