How to close Popup-Menu ?

Hi !

I open a PopupMenu with TrackPopupMenu. Now I want to close this menu from my programm (without the user clicking anywhere. This is because the mouse has reached another menu for example). How can I close an open PopupMenu from the code ? I didn't find anything like "CloseMenu", and another call of TrackPopupMenu does nothing, when another Menu is opened. Please help !

Regards

Martin