At the beginning of the episode, when Frasier and Niles (David Hyde Pierce) are speaking in the coffee shop, Kelsey Grammer stumbles on his words. As Niles remarks, Frasier had stumbled on his words: Grammer had, in fact, said "Flasier." But the two actors had improvised so well (and it was the end of the scene) that the take was used.
The title is based on a famous palindrome: A man, a plan, a canal, Panama! (Read it backwards!)
This is the first episode of the series in which Peri Gilpin does not appear. Other than Jane Leeves's maternity leave in Season 8, this is the only instance in which one of the main cast members is absent. When this episode first aired, however, it aired immediately after the previous episode. Gilpin also did not appear in "The Babysitter (2003)," two episodes later.
At the beginning of the episode, Daphne tells Niles, "It's official. Dr. Lee says we're pregnant." This is a possible nod to long-time Frasier producer David Lee.
The first line in this episode is Daphne saying, "It's official. Doctor Lee says we're pregnant." It's amusing to hear that some doubt existed about it with Jane Leeves' abdomen sticking out as it is. She was clearly pregnant herself at the time with her son Finn William Leeves Coben, who was born December 19, 2003, less than three months after this episode aired.