Cocoa: No context menu events on a unified toolbar

#include <QtGui>

class MyToolBar : public QToolBar
{
public:
    MyToolBar ( QWidget * parent = 0 ) : QToolBar(parent)
    {
    }

    void contextMenuEvent ( QContextMenuEvent * event )
    {
        qDebug() << "contextMenuEvent found in MyToolBar";
    }
};

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QMainWindow win;
    MyToolBar *myToolbar = new MyToolBar(&win);
    myToolbar->addAction("one");
    myToolbar->addAction("two");
    win.addToolBar(myToolbar);

    win.setUnifiedTitleAndToolBarOnMac(true);
    win.show();

    return app.exec();
}