Tim Hicks wrote: > def sort_id(ob1, ob2): > return cmp(ob1.getID(), ob2.getID()) > > It seems that the cmp function needs to get hold of attributes, not methods. > Even if I specifically call a method on ob1 or ob2, getattr seems to be > called in there somewhere. > > Any more clues? try getId() instead of getID() Maarten.