When working in Flash/Flex with idioms that have characters others than those that exist in english you'll need to work a little more. Whatever it is, a so different idiom as japanese, with its three distinct alphabets,  or only to include accentuation in latin languages.

When you create a swf, Flash or Flex automatically embed the characters of your static text with the font you choose, increasing the size of your final file. However, when you use dynamic text (coming from database, XML, user's input or rotated and deformed text) the problem with alphabets appears.