StageText ReturnKeyLabel.DONE, KeyboardEvent not dispatched on Nexus 5

Hello,

On Android nexus 5, when ReturnKeyLabel.DONE in a StageText, KeyboardEvent is not dispatched

public function Main() {
  stage.scaleMode = StageScaleMode.NO_SCALE;
  stage.align = StageAlign.TOP_LEFT;
  addEventListener(Event.ADDED_TO_STAGE, init);
}
private function init(event:Event):void {
  var decoration:Sprite = new Sprite();
  decoration.graphics.lineStyle(4, 0x000000, 1);
  decoration.graphics.beginFill(0xFFFFFF, 1);
  decoration.graphics.drawRect(6, 44, stage.stageWidth-12, 70);
  this.addChild(decoration);

  var stageText:StageText = new StageText();
  stageText.returnKeyLabel = ReturnKeyLabel.DONE;
  stageText.fontSize = 40;
  stageText.stage = this.stage;
  stageText.viewPort = new Rectangle(10, 50, stage.stageWidth-20, 70);
  stageText.addEventListener(KeyboardEvent.KEY_DOWN, keyDownEventHandler);
}
private function keyDownEventHandler(evt:KeyboardEvent):void {
  if(evt.keyCode == Keyboard.ENTER)  evt.target.text="Enter key";
}

KeyboardEvent is dispatched if

stageText.returnKeyLabel = ReturnKeyLabel.GO;

Thanks