Об этом дополнении
* kanji pronunciation changed to Korean, triggers on hangul or hanja
* REQUIRES DICTIONARY ADDON (called Mukparasi Korean-English dictionary)
* tracks rikaichan version numbers (use version 2.09.12 to avoid commented bug, please leave a comment if it works)
* if you have chrome and don't need Thunderbird/Seamonkey integration you can also try Toktogi (dictionary will be the same though AFAIK, if you know of a good English/Korean open source dictionary apart from kengdic, contact me and the Toktogi author)