Originally Posted by Stormchild
Unfortunately it is not possible to user select the font for Epub/PDF without recoding the books. Well not easily. The firmware uses Adobe Reader which prevents this. There are alternatives but the simple answer is get your books already in Japanese or use another format.
Not quite true. On the Bebook Club you can select to open Epubs in FBReader, and then you can select fonts (although for some reason this does not work for all epubs). And it's also very easy to convert epubs for instance to mobi or fb2, formats which are always opened in FBReader and which always allow you to select a font.