QWidget project cannot receive Android 'Menu' hardware key

We need to make our Qt app interact with the Android 'Menu' hardware key. So far we can interact with the 'Back' and 'Search' keys OK. Here is the code that does not work (MainWindow class is derived from QWidget).

void MainWindow::keyPressEvent(QKeyEvent *ev)
{
int key = ev->key();

if (key == Qt::Key_Menu)

label5->setText(QString("Hey you just hit the (%1) key").arg(key));
QWidget::keyPressEvent(ev);
}

This code will display the Search-key code when pressed, but there is no output at all when the 'Menu' key is pressed.

Regards,
Chris