Jack
Unicode characters do show up in .txt and .html files, if the files are encoded properly (UTF8). With the .epub the situation is a bit different. Epub files with no embedded fonts are displayed using the internal Adobe font which, besides the standard English alphabet, supports very few special characters. If you need full Unicode support in .epub, you would have to embed at least one unicode font in the .epub package. I tried this and it works.
Hope this helps.
Peter