Making only content visable inside of movie dimentions

this is quite possible a stupid question but,

i have a movie which is 600x500, it has animation inside of it but some of the tweens go over the border (outside of the 600x500 stage).

I have used the noScale setting so the user canot scale the movie.
But in flash player when i expand it and in my web browser you can see the gfx that go over the border of the movie.

I just want it so the user cannot scale and also so outside of the 600x500 stage nothing is displayed, so in a browser for example the 600x500 flash movie would sit in the middle with a thick white border around it (depending on screen resolution).

What do i need to do to achieve this? thanks