     //  popUpPosition
     //----------------------------------
 	
-	private var _popUpPosition:String = "exact";
+	private var _popUpPosition:String = RelativePosition.EXACT;
 	
 	/**
 	 *  Position of the popUp when it is opened. 
 	 *  Possible values are "left", "right", "above", "below", "center", and "exact"
 	 * 
-	 *  @default "exact" 
+	 *   
+	 *  @default RelativePosition.EXACT
+	 * 
+	 *  @see spark.core.RelativePosition
 	 * 
 	 *  @langversion 3.0
 	 *  @playerversion Flash 10

	{
		switch(placement)
		{
			case "below":
				registrationPoint.x = 0;
				registrationPoint.y = unscaledHeight;
				break;
			case "above":
				registrationPoint.x = 0;
				registrationPoint.y = -popUpHeight;
				break;
			case "left":
				registrationPoint.x = -popUpWidth;
				registrationPoint.y = 0;
				break;
			case "right":
				registrationPoint.x = unscaledWidth;
				registrationPoint.y = 0;
				break;			
			case "center":
				registrationPoint.x = (unscaledWidth - popUpWidth) / 2;
				registrationPoint.y = (unscaledHeight - popUpHeight) / 2;
				break;			
			case "exact":
				// already 0,0
				break;
		}

				// then revert to the original position. 
				switch(adjustedPosition)
				{
					case RelativePosition.BELOW :
						if (popUpBounds.bottom > screen.bottom)
							adjustedPosition = null; 
						break;
					case RelativePosition.ABOVE :
						if (popUpBounds.top < screen.top)
							adjustedPosition = null; 
						break;
					case RelativePosition.LEFT :
						if (popUpBounds.left < screen.left)
							adjustedPosition = null; 
						break;
					case RelativePosition.RIGHT :
						if (popUpBounds.right > screen.right)
							adjustedPosition = null;  
						break;
