Here's another tidbit from the Associated Press:
GUEST STARS ON FINAL "SEINFELD" EPISODE (New York) -- The Soup Nazi will pop up in the final "Seinfeld" episode. "Entertainment Weekly" has gotten its hands on some cast information for the last show. It says Larry Thomas will be back as the Soup Nazi, so will Jerry and George's parents. Even Frances Bay, who played the old woman Jerry mugs for a marble rye, will make an appearance. Other characters who could get guest shots include Uncle Leo, Poppie, Mickey the midget, Tim the dentist -- and former Mets first baseman Keith Hernandez.