Modal dialog and google maps (loosing mouse events)

Modal dialog and google maps (loosing mouse events)

UI Modal dialog 1.8.0 on jquery 1.4.2 with à Google map v2 on it, does not stop dragging the google map when the mousebutton is released.
 
This does NOT work in Chrome and FireFox but works ok in IE 8.0
 
As soon as I make the dialog non-modal the map works as expected.
 
So it looks like a ui-modal-dialog does not return the mouse-up event.
 
How could I fast solve this? I was so dumb to not check enough when coming from 1.7....
 
Regards,
Henk