in prs-350 works the same way? Probably. But I want to know about epub in dr-900.
In this video (
http://www.youtube.com/watch?v=xqyNq36hlJQ , 7:45) it looks like you first have to open bottom menu, than tap Dictionary than select/tap word. Thats way to much touching on such slow screen for an action as basic as dictionary lookup. but I think file opened in video was pdf.
tnx
grega_g