Gtk::Dialog::on_delete_event() is never called

[Tobias Eberle <tobias eberle gmx de>]

Hallo,

I want to prevent that the user can close a dialog (derived from
Gtk::Dialog) by clicking on the X. I tried to override
on_delete_event():

class CMyDialog : public Gtk::Dialog
{
  //...
  protected:
    bool on_delete_event(GdkEventAny *);
}

but on_delete_event() is never called. Is this a bug or is there another
mechanism to catch the delete event?

Thanks.

Tobias