[flexcoders] How can I automatically scroll a VBox when an item is drug near the top or bot?

[invertedspear]

I have a VBox containing a bunch of panels. I have implemented dragging and 
dropping but I need to be able to scroll automatically when the item is drug 
near the edge. I am having mixed results. I can get it to work, but not well. 
My example is below. It works if the user bounces their mouse around a little 
near the top or bottom edge, but I want it to work if they just hold the mouse 
there. Any suggestions?

On Mouse down (I'm doing several other things but this is one of them):

VBox(di.parent).addEventListener(MouseEvent.MOUSE_MOVE,autoScrollSection,true,500);

On dragDrop

VBox(evt.currentTarget.parent).removeEventListener(MouseEvent.MOUSE_MOVE, 
autoScrollSection,true);

Here is the autoScroll function:

private function autoScrollSection(evt:MouseEvent):void{
    var tempVBox:VBox = VBox(evt.currentTarget);
    if(tempVBox.mouseY<50){
        tempVBox.verticalScrollPosition += -50;
    }
    if(tempVBox.mouseY> int(tempVBox.height-50)){
        tempVBox.verticalScrollPosition += +50;
    }
}

So if they are within 50px of an edge then it should scroll by 50px. I've 
exaggerated the numbers just to get an affect.