I dont thing this is possible using AS2 alone.
As3 has a load and save option for other format files and may be possible there there are ways round though.
The following site has a download available for viewing pdfs from flash so you could use than and call in the pdf to that and that swf to a MC in your movie.
http://flexpaper.devaldi.com/default.jsp
Other options a fscommand, using VB.

I may be wrong but searching around thats all I can find.