Setting a stroke style on a Skinnable container?

Question

I have a SkinnablerContainer skin that I made using the "new skin from copy".  I've got it working with the fill properties included, but I'd also like to add some control for stroke.  I did this, but the component instance says "Cannot resolve attribute 'borderWeight' for component type spark.components.SkinnableContainer".
<fx:Script fb:purpose="styling">
    <![CDATA[        
         *  @private
        override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number) : void
            bgFill.color = getStyle("backgroundColor");
            bgFill.alpha = getStyle("backgroundAlpha");
               bgStroke.color = getStyle("borderColor");
               bgStroke.weight = getStyle("borderWeight");
            super.updateDisplayList(unscaledWidth, unscaledHeight);
    ]]>       
</fx:Script>
<s:states>
    <s:State name="normal" />
    <s:State name="disabled" />
</s:states>
<s:Rect left="0" right="0" top="0" bottom="0" radiusX="12">
    <s:fill>
        <s:SolidColor id="bgFill"/>
    </s:fill>
     <s:stroke>
          <s:SolidColorStroke id="bgStroke"/>
     </s:stroke>
</s:Rect>

Answer 1

OK, so what component could I use that supports a borderColor? 
Also, in the past I have "made up" my own styles:
<s:Skin xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark"
          minWidth="21" minHeight="21"
          alpha.disabled="0.5">
     <fx:Metadata>
          [HostComponent("spark.components.Button")]
     </fx:Metadata>
     <fx:Script>          
          [Bindable] private var tColor:uint;
          [Bindable] private var tColorOver:uint;
          [Bindable] private var tColorDown:uint;
          [Bindable] private var tColorDisabled:uint = 0xCCCCCC;
          override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number):void
               bgcolor.color = getStyle("backgroundColor");
               bgcolorover.color = getStyle("backgroundOverColor");
               bgcolordown.color = getStyle("backgroundDownColor");
               tColor = getStyle("color");
               tColorOver = getStyle("colorOver");
               tColorDown = getStyle("colorDown");
               super.updateDisplayList(unscaledWidth, unscaledHeight);
     </fx:Script>
     <s:Rect top="0" left="0" right="0" bottom="0" radiusX="6" radiusY="6">
          <s:filters>
               <s:BevelFilter strength=".3" distance="2" blurX="4" blurY="4"/>
          </s:filters>
          <s:filters.down>
               <s:BevelFilter strength=".3" distance="-2" blurX="4" blurY="4"/>
          </s:filters.down>
          <s:fill>
               <s:SolidColor id="bgcolor" />
          </s:fill>
          <s:fill.over>
               <s:SolidColor id="bgcolorover" />
          </s:fill.over>
          <s:fill.down>
               <s:SolidColor id="bgcolordown" />
          </s:fill.down>
     </s:Rect>
Why does it work here?  Or does this only support css and not mxml?