private var mySprite:Sprite;
private var adjColor:AdjustColor;

and in the function myClass:

mySprite = new Sprite(); // No need to redeclare
adjColor = new AdjustColor();

Sorry for the mistake, I just wrote the whole thing in this textarea here, I guess my brain was locked in scramble mode :-p

package
{
import flash.display.*;
import fl.motion.AdjustColor;
import flash.filters.ColorMatrixFilter;
import fl.transitions.*;
import fl.transitions.easing.*;

public class myClass extends Sprite
{
private var mySprite:Sprite;

public function myClass()
{
var mySprite:Sprite = new Sprite();
mySprite.graphics.beginFill(0xFFFF00);
mySprite.graphics.drawRect(0, 0, 150, 100);
mySprite.graphics.endFill();
addChild(mySprite);

var adjColor:AdjustColor = new AdjustColor();
adjColor.saturation = 0;
adjColor.contrast = 0;
adjColor.brightness = 0;
adjColor.hue = 0;

colorTween = new Tween(adjColor, “hue”, None.easeIn, 0, 125, 2, true);

colorTween.addEventListener(TweenEvent.MOTION_CHANGE, updateColors);
}

private function updateColors(e:TweenEvent):void
{
var cmf:ColorMatrixFilter = new ColorMatrixFilter(adjColor.CalculateFinalFlatArray());
mySprite.filters = [cmf];
}
}
}

I hope it’s useful for someone