Other mistake: Both sides (American & German) use the same tanks! The American tanks have white stars painted on them, while the German tanks bear white Maltese Crosses.
Continuity mistake: In order to tiptoe across the tacks without being hurt, Tom puts a metal gauntlet on his feet. At this point, you can see the floor is completely covered in tacks, but when Jerry and Nibbles are at the same spot a little later on, the tacks have disappeared.
Continuity mistake: When Will Stockdale is at the Purple Grotto, at one point the cup full of liquor is at different levels.
Visible crew/equipment: When Isabel Jeans is telephoned by Madame Alvarez and told that Gigi has refused Gaston's advances, she gets out of bed and walks across the bedroom. As she passes a cheval (full length) mirror a pair of retreating jean-clad legs and a hand feeding out cable can be seen in the reflection.
Audio problem: When Strong is running away from Norah he passes the Sgt. The screams he is making are overdubbed as his mouth isn't moving. (00:57:45)
Revealing mistake: In the opening credits, Richard Widmark is driving a car with Doris Day in the passenger seat. Widmark does not turn the steering wheel, even though the rear-screen projection shows him going around a curve.
Factual error: The film is set during WW2, but when Pitkin drops Judy off at the station, the locomotive bears the lion and wheel emblem of 'British Railways', which was formed in 1948. Likewise the wagons in the railway yard are to a British Railways standard design and are out of period for WW2.
Audio problem: When Bugs says "I just hope I will be in one piece, so I can appreciate it", his mouth is not moving.
Continuity mistake: When Jeannie is on the settee talking on the telephone, the cord is missing in some shots.
Continuity mistake: When King Arthur says "A good idea, fool!", Bugs Bunny stops and you can see that behind him is a wall. In the next shot, Bugs is now in front of King's Arthur's chair, and when he says "Beheaded?" he is back in front of the wall again.