When Ajax precondition fails no post event handler is called

[Thijs]

Hi,

We have an overlay that is triggered by a ajax global event listener. like:
Wicket.Event.subscribe('/ajax/call/before', function(jqEvent, 
attributes, jqXHR, errorThrown, textStatus) {
showBusysignAjax();
});

Put when the precondition of the ajax call fails none of the 
'/ajax/call/after|complete|failure|success is called causing the overlay 
to keep being displayed.

When a precondition fails, doesn't the '/ajax/call/failure|complete'  
need to be called?

Thijs