Originally Posted by JimmXinu
As for default language, except for the few language specific sites and ffn, FFDL does default the language to English('en') inside the epub. It doesn't set the language in calibre in that case. Something about that feels familiar, like it's come up before--I'll check old postings and get back to you.
@Dylan Tomorrow - I can't find anything about it now. What did you do exactly to add the language so it worked correctly for you?