Kotoeri doesn't work anymore in Mountain Lion

So the Kotoeri input method doesn't work anymore. I've selected Italian and Kotoeri with Hiragana, Katakana, Romaji and Full width Romaji. The first few times I switched from the usual Italian to Hiragana, it took 15 seconds to load (2008 model) but then it worked fine, converting letters to kana. But I don't know why it's not been working for days now: when I switch to Kotoeri it takes 15 seconds to load but then it simply type in Italian, and the text isn't even underlined (so it's not trying to convert to kana). I've tried to unselect-reselect it from the preferences but it won't fix. Can you help me?