FLEX中使用BitmapFill的source属性指定SVG类文件

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"
                backgroundGradientColors="[#333333, #222222]"
                xmlns:degrafa="com.degrafa.*"
                xmlns:paint="com.degrafa.paint.*"
                xmlns:geometry="com.degrafa.geometry.*">              
    <degrafa:Surface verticalCenter="0" horizontalCenter="0">
        <degrafa:fills>
            <paint:BitmapFill id="bitmapFill" source="{svgTest}" smooth="true"/>
        </degrafa:fills>
        <degrafa:GeometryGroup scaleX="1" scaleY="1">
            <geometry:Circle fill="{bitmapFill}" radius="450"/>
        </degrafa:GeometryGroup>
    </degrafa:Surface>
 <mx:Script>
  <![CDATA[
   [Embed(source="circle.svg")]
   [Bindable]
   public var svgTest:Class;
  ]]>
 </mx:Script>
</mx:Application>

circle.svg:

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN"
  "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
<svg width="200" height="200" xmlns="http://www.w3.org/2000/svg">
  <desc>All SVG documents should have a description</desc>
    <defs>
      <!-- Items can be defined for later use -->
  </defs>
   <g>
      <circle cx="15" cy="15" r="15" fill="red"/>
  </g>
</svg>