One of the surprisingly time consuming tasks when making a localized (multi-language) site is deciding on which characters you want to embed. In the flash IDE there is a few default sets. If u find those sets to be insufficient but have your own that you would like to add to the IDE check out this article.
If u want be very exact and only use exactly characters you know will be on there you can get a custom set from a text file using this handy dandy page.
http://www.epic.dk/flash-unicodetable/flash-unicodetable-generator.php