I have the following problem:
get the zeit epub from zeit.de
get it via this plugin.
View the documents with an epub reader (I tested it with fbreader on a pocketbook and the calibre epub reader).
Plugin epub: only the main index page links work fine, every other link (e. g. sub indexes, "next article...") do not work (clickable but you are not forwarded anywhere)
Original epub: every link works fine
I am not shure when this effect occured but I think it is since the images are inserted in the original epub.
Yes, it is possible to let the epub sent by zeit.de but I have a cron job with some recipes running daily/weekly which puts the epubs into my home web server database automatically and this is definitely easier than import an epub from an imap server