@parazhang: Yep, that would do it (By Serif_*, I mean Serif_Regular, Serif_Bold, etc. Check the firts post for the full proper naming scheme).
And yep, there are a bunch of info on this right in this thread, do a search by messages

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Note that if you want CJK support in the browser, you might have to switch the other two families (Sans, Mono) with CJK-aware fonts too.