In The Stand-In, "Packyderm" is referred to in an apparently hilarious story, and George's girlfriend breaks up with him to date Jerry Persheck (aka Packyderm).
JERRY: Fulton's wife told me it's all my fault. She said since my visit he's taken a turn for the worse.
KRAMER: Did you tell him the Packyderm story?
JERRY: (yelling) Yes I told him the Packyderm story!