Undefined coordinated in a class (FL8 & AS2.0)

I have a class I am building that will attach a circle inside a designated MC. The circle then uses startDrag() to follow the mouse. There is a method called display_range that does all the movement stuff.


public function display_range ():Void {
		dest_circle = range_mc.createEmptyMovieClip("destination", 50);
		dest_mc.startDrag (true);
		range_mc.onMouseMove = function () {
			update_position ();
			trace (dest_mc._x + ", " + dest_mc._y);
		};
		trace (dest_mc._x + ", " + dest_mc._y);
		trace (point.x + ", " + point.y);
		trace ("-------");
	}
private function update_position ():Void {
		point.x = dest_mc._x;
		point.y = dest_mc._y;
	}

the initial trace displays the coordinates, but when tracing the coordinates of the dest_mc inside the onMouseMove event it shows undefined. What gives?