Other mistake: Mick the orderly is Irish throughout the film, but when Nurse Dawson bumps into him and says, "You clumsy oaf," Mick's reply, "Look who's talking," is said in a London accent.
Continuity mistake: When we first see the Colonel reading a newspaper the headline on the page he is reading starts with the word "Birmingham", but when the camera angle changes it reads "Fontwell Park".