Controlling a movieclip that loads external swfs

I have a button that stops a movie clip, the only thing is when I load an external SWF and use that movieclip as the container, it stops working.

I gave the movieclip an instance name “trans” and when i use
[AS]
trans.loadMovie(“trans.swf”)
[AS]

To load an external SWF called trans the following AS

[AS]
on (release) {
_root.trans.stop()
}
[AS]

stops working… ANy suggestions

Mike