 				var child:IUIBase = contentView.getElementAt(i) as IUIBase;
 				if (child == null || !child.visible) continue;
 				ilc = child as ILayoutChild;
-				var left:Number = ValuesManager.valuesImpl.getValue(child, "left");
-				var right:Number = ValuesManager.valuesImpl.getValue(child, "right");
+				var left:Number = NaN;
+                cssValue = ValuesManager.valuesImpl.getValue(child, "left");
+                if (cssValue !== undefined)
+                    left = CSSUtils.toNumber(cssValue);
+                var right:Number = NaN;
+                cssValue = ValuesManager.valuesImpl.getValue(child, "right");
+                if (cssValue !== undefined)
+                    right = CSSUtils.toNumber(cssValue);
 				margin = ValuesManager.valuesImpl.getValue(child, "margin");
                 marginLeft = ValuesManager.valuesImpl.getValue(child, "margin-left");
                 marginTop = ValuesManager.valuesImpl.getValue(child, "margin-top");

			var marginBottom:Object;
			var margin:Object;
			var maxWidth:Number = 0;
			// asking for contentView.width can result in infinite loop if host isn't sized already
			var w:Number = hostSizedToContent ? 0 : contentView.width;
            var h:Number = contentView.height;

	import org.apache.flex.core.ValuesManager;
	import org.apache.flex.events.Event;
	import org.apache.flex.events.IEventDispatcher;
	import org.apache.flex.geom.Rectangle;
	import org.apache.flex.utils.CSSContainerUtils;
	import org.apache.flex.utils.CSSUtils;
	import org.apache.flex.utils.dbg.DOMPathUtil;
	
	/**
	 *  The VerticalLayout class is a simple layout
