Originally Posted by jgray
Now, the idea of a multi-format reader that could open an epub ebook and lookup words with a mobi dictionary has occured to me before, but no one has implemented that to my knowledge. It would be a good interim measure and would immediately give that particular device access to the wide variety of mobi dictionaries.
There seems to be a problem with licensing, see Bookeen's case. They're going to maintain two firmware versions, because the license doesn't allow them to fit the mobi and the epub support into a single firmware. So mobi is definitely not a good interim solution. I would rather propose open XDXF format as an interim solution until a proper epub dictionary format with drm support is introduced.