Constraining the dragable area of a movieclip

Hi,

I’ve had a look around the tutorials and forums but still can’t seem to solve this problem.

I’ve got a movie clip with the following code;

on(press){
startDrag(this);
}
on(release,releaseOutside){
stopDrag();
}

I only want the clip to be draggable within a rectangular area on my main stage. How can I put in the constraints?

Thanks for any help