eZ Find's autocomplete functionality does not work, on both backend and frontend siteaccesses, with Kanji and Hiragana Japanese characters. However, is does work with katakana characters.
1. Configure CJKTokenizer in solr. Following SOLR's example (http://svn.apache.org/repos/asf/lucene/dev/branches/lucene_solr_3_6/solr/example/solr/conf/schema.xml), I added the following block to ./ezpublish_legacy/extension/ezfind/java/solr/conf/schema.xml:
Please note that you must re-start SOLR for the changes to take effect. Re-indexing in not necessary, though.
2. Create Japanese content. For the sake of completeness, I created content in Kanji, Hiragana and Katakana:
Kanji: 漢字(かんじ) no auto-complete
Hiragana: ひらがな no auto-complete
Katakana: カタカナ auto-complete works