Kai Wiesinger and Heinrich Schafmeister, who have a short scene together in 'Kleine Haie', would later perform in the movie The Harmonists (1997) together, both playing members of this famous a Capella group. 'Kleine Haie' opens with a Comedian Harmonists-song.
I don't mean to meddle in things that aren't my business, but do you think it's OK, drinking beer?
Bierchen: I think beer is OK.
Johannes: Yes, but while driving?
Bierchen: I think driving-beer is OK.
After the casting credits Ingo reappears and tells what happens to the main characters after the film.