Following yesterday’s iBooks 1.1 update, users have discovered that Apple’s built-in dictionary is no longer working with some e-books, a problem traced by iLounge’s editors to a difference in the way iBooks 1.1 chooses dictionaries relative to versions 1.0 and 1.01. The new iBooks appears to be using the language identifier normally stored within ePub files to determine which dictionary to use for a given e-book.
Some popular e-book conversation applications such as Calibre do not insert the correct language identifier when saving in the ePub format, which will result in iBooks not knowing which dictionary to use. The problem appears to be confined to e-books that users have converted themselves or downloaded from third-party sources outside of the iBookstore, despite the fact that dictionary lookups for these books worked fine prior to the iBooks 1.1 update.
More information on this problem and how to fix it can be found in our Backstage section.