GradientFill bug?

var blob:Sprite=new Sprite();
addChild(blob);
var gradsize:int=20;

for(var i:int=0;i<100;i++){
    var matrix:Matrix = new Matrix(); 
    matrix.createGradientBox(gradsize,gradsize,0,(i % 10)*gradsize,int(i/10)*gradsize);
    blob.graphics.beginGradientFill(GradientType.RADIAL,[0,0],[1,0],[0,255],matrix);
    blob.graphics.drawRect(0,0,stage.stageWidth,stage.stageHeight);
}

Try the code. I am drawing 100 rectangles with gradient fills at different locations. However, it only shows the last 23 gradients on my computer. Anyone know why? and how to fix?