The Baby Name Pages I found list Teijo as japanese male Name, one Page
is listing it as a Variant of Teiji.
I don´t think that they confused it, cause they all say Teijo means righteous; well governed, and this meaning is totally different than the finnish version.
Well, probably I have to call the International Names Office and they have to search :-(
Do you think if he would use it as a stage name, that he would use a girls name (if Teijo would be only for girls?).
By the way, Taro
is also a boy Name and ends with -o.
Well, its really complicated *rolleyes* but thank you very much for your help ;-)