My understanding is that Word for Mac in MS Office Mac versions since Office 98 have used the same file format as Windows versions -- Word 97 and later. That means that Word for Mac can read files containing any Unicode characters.
It doesn't work. They seem always to get converted into underscores.
Input and rendering, however, are limited to legacy codepages supported by the Mac OS. Thus, e.g. you should be able to work with Chinese text (at least some Chinese characters), but you wouldn't be able to work with Ethiopic text.
I don't know about Chinese, but it appears that one is limited to WorldScript. Word hasn't been updated for Mac OS since 2001.
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Michael Everson * * Everson Typography * * http://www.evertype.com
