missing click-event on the GPolylilne

according to the api there must be an click-event on the polyline:
click -> overlay, point

I tried to bind a clickevent to a polyline like this:

var polyline = new GPolyline(points, color);

GEvent.addListener(polyline, 'click', function() {
alert("helllo");
});

but it doesn't work. where's the mistake?
thanks for any help and merry xmas!!!