Getting duration from netstream or video

So I’m creating a custom video player. Granted I know I could just skin the components (I am really excited about the runtime skinning), but I started this before cs3 and now just want to get it done. The only problem is I see no way to determine the duration of the movie which makes it impossible to make a scrubber, where is it or am I just missing something I know the client has some functionality but I can’t find any doco on it. Any help would be appreciated.