function openWindow( url, name, breite, hoehe ) {
	  links = ( screen.width / 2 ) - ( breite / 2 );
	  oben = ( screen.height / 2 ) - ( hoehe / 2 );
	  window.open( url , name, 'height = ' + hoehe + ', width = ' + breite + ', status = no, toolbar = no, menubar = no, location = no, resizable = no, titlebar = no, scrollbars = yes, fullscreen = no, top = ' + oben + ', left = ' + links );
}