@Jakob
Ah, yes. From Qt4 you get:
# define Q_SIGNALS protected
I firmly believe that this change was made to accommodate the new way of connecting signals. I don't find it to be a great improvement, but this is a personal opinion ... In the new framework it seems every object can easily rise another object's signal, which is a bit ... hm ... suspicious ... not that it was impossible before, but you had to go the extra mile, by using the QMetaObject class.