Animating color of text with TweenMax

[froinds]

Hello,
Basically I have a menu with submenus. The submenu is a Sprite with two children, one is a square for the background and the text on top.
On mouse over, I can change the color of the first child, the background, but not the color of the text, the second child.
Here is the code.

private function subMenuItemOver(evt:MouseEvent):void {
     TweenLite.to(evt.target.getChildAt(0), 1, {tint:0x9ca26e}); // Works
     TweenLite.to(evt.target.getChildAt(1), 1, {tint:0xffffff});    // Doesn't work
}

The menus are created from an xml document and the color is assigned with TextFormat.

I have no idea why I can't animate the color of the text.

Thanks in advance.