Other mistake: When Jack first arrives in Christmas Land he doesn't know what is falling from the sky (snow) but he somehow knows that the children are throwing snowballs.
Continuity mistake: One of the tiles comes loose when Wallace is walking across the ceiling in the museum. A few seconds later, the tile is flat against the wall again.
Continuity mistake: After Bruce proposes to Andrea and he drops her off at home, she is wearing the ring on her left hand when she is inside his car. But once she steps out of it, the ring completely disappears.
Continuity mistake: When Bob tells Junior that Larry is a cucumber, the carpet and the shadow of Junior's bed shift to the right a little bit.