This question has been raised on the [[Wikisource:Scriptorium]] and is well beyond my capacity to answer.
I'm in trouble. Why does MediaWiki1.4b3 change CJK Compatibility Ideographs to CJK Unified Ideographs? see 狩獵免許稅徵收ニ關スル法律 http://wikisource.org/wiki/%E7%8B%A9%E7%8D%B5%EF%A8%B2%E8%A8%B1%E7%A8%85%E5%BE%B5%E6%94%B6%E3%83%8B%E9%97%9C%E3%82%B9%E3%83%AB%E6%B3%95%E5%BE%8B. 免 changed into 免. -
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