Sometime in the last year or so, I started using GG Superscript and GG Subscript fonts. You can find them by doing a web search. They are a free download and if you embed them into your flash program, your users will be able to see the superscripts and subscripts. Make sure you test your swf file on a computer that doesn't have the fonts so that you can be sure you embedded the fonts properly.
I want to share with you the way I get may subscript and superscript inin dynamic and input text field in Flash:
<sub> & <sup> tags are not supported by Flash but you can
use Subscript & Superscript in dynamic and input text field in Flash:
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