Continuity mistake: When Jingle, Jangle, and Mrs. Claus pay a visit to Mother Nature, Mother Nature calls her sons beside her - Snow Miser and Heat Miser. She then turns to Snow Miser and asks him to allow a little snow fall in the South, and then turns to his brother, Heat Miser, and asks to allow just "one Spring day at the North Pole." The words are correct dialog, but she should have said each of those lines to the OTHER brother. (00:39:40)
Factual error: At the end of the movie, Mame takes Peter with her on a trip to Siberia. However, at this point in the timeline, it's the late 1940s, meaning that Stalin was still in power, so even Auntie Mame would be crazy to think of vacationing in Russia. Not to mention the difficulties of getting Peter a visa to travel to the USSR at the last minute. (In the stage version, the destination was India, rather than Siberia, which makes a lot more sense).