QGraphicsScene::mouseMoveEvent Question

[harakiri]

hi, i have a QGraphicsScene in a QGraphicsView:

view = new GraphicsView( this );
 scene = new GraphicsScene( this );
 scene->setSceneRect( 0.0, 0.0, 512.0, 512.0 );
 scene->add....(...
 ....
 view->setScene( scene );
 view->show();

view = new GraphicsView( this );
 scene = new GraphicsScene( this );
 scene->setSceneRect( 0.0, 0.0, 512.0, 512.0 );
 scene->add....(...
 ....
 view->setScene( scene );
 view->show();

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all objects added to the scene are displayed correctely, but

void GraphicsScene::mouseMoveEvent( QGraphicsSceneMouseEvent *event ) {
  cout << " moved to: X->" << event->pos().toPoint().x();
  cout << " moved to: Y->" << event->pos().toPoint().y() << endl;
  event->accept();
}

void GraphicsScene::mouseMoveEvent( QGraphicsSceneMouseEvent *event ) {
  cout << " moved to: X->" << event->pos().toPoint().x();
  cout << " moved to: Y->" << event->pos().toPoint().y() << endl;
  event->accept();
}

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always results in X->0 and Y->0
why is that so?