Special Guest Stars Kelsey Grammer voices Sideshow Bob Scott Bakula voices Himself Steve Ballmer voices Himself Guest Stars Pamela Hayden voices Milhouse Van Houten Pamela Hayden voices Jimbo Jones Tress MacNeille voices Dolph Shapiro Kevin Michael Richardson voices Security Guard Chris Edgerly voices Santa Claus Kevin Michael Richardson voices Police Guard Kevin Michael Richardson voices Boarding School Manager Tress MacNeille voices Cassandra Patters Tress MacNeille voices Random Childon