It sure is!
I'd like to add that I'm using a slightly different approach, I'm using the an image fill for a rectangle:
<s:Rect id="backgroundRect" left="0" right="0" top="0" bottom="0" >
<s:fill>
<s:BitmapFill source="@Embed('skins/pattern_147.gif')" fillMode="repeat" />
</s:fill>
</s:Rect>