Run the application on windows and move the QGraphicsLineItem, this will not update correctly. This works in 4.5.3 but not in 4.6.0 beta 1.

#include <QtGui>

int main(int argc, char *argv[])
{
QApplication app(argc, argv);

QGraphicsView view;
QGraphicsScene scene;;
scene.setSceneRect(0,0,200,200);
view.setScene(&scene);

QGraphicsLineItem item;
item.setLine(0,100,100,100);
item.setFlags(QGraphicsItem::ItemIsSelectable | QGraphicsItem::ItemIsMovable);

scene.addItem(&item);

view.setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
view.setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
view.show();

return app.exec();
}