flex 3 Smooth Scroll Example Enjoy :)

mx|ScrollBar
{
track-skin: Embed(source='assets/scroll/thumb.png',
scaleGridLeft="2", scaleGridTop="6",
scaleGridRight="7", scaleGridBottom="9");
up-arrow-skin: ClassReference("undefined");
down-arrow-skin: ClassReference("undefined");
thumb-up-skin: Embed(source='assets/scroll/thumb_up.png',
scaleGridLeft="3", scaleGridTop="3",
scaleGridRight="10", scaleGridBottom="11");
thumb-over-skin: Embed(source='assets/scroll/thumb_up.png',
scaleGridLeft="3", scaleGridTop="3",
scaleGridRight="10", scaleGridBottom="11");
thumb-down-skin: Embed(source='assets/scroll/thumb_up.png',
scaleGridLeft="3", scaleGridTop="3",
scaleGridRight="10", scaleGridBottom="11");
}