Insanely annoying startDrag issue.. please help

ive never been able to solve this problem.

i want to make a simple scrollbar. so i draw out the scrollbar on my stage, and i want to lock the scroller to a vertical line, which is easy. my code is like this:

MyScroller.onPress = function() {
startDrag(this, true, 200, 20, 200, 600);
}

MyScroller.onRelease = function() {
stopDrag();
}

as you can see it stops the scroller from moving anywhre on the X axis.

it works… EXCEPT… if i move my mouse outside of the MyScroller movieclip while the mouse is still held down, the scrollbar continues to drag… but if i let go of the mouse with the cursor outside of the movieclip, the onRelease NEVER triggers, and the movieclip drags indefinitely.

so how the hell do i stop this? i obviously want it so that if you start dragging the scrollbar, then move the mouse outside of the movieclip and release it, it should stop dragging. cant figure it out tho.