During the "In Memoriam" segment a shot of the famous spaghetti eating scene in Lady and the Tramp is shown behind Ollie Johnston. Johnston did not actually animate this scene. Fellow "Nine Old Men" member Frank Thomas animated the scene.
Just before the presentation of "Best Supporting Actress" the curtain that was supposed to open to reveal the presentation screens don't open. You can then hear a stagehand from backstage yell, "We're doing it. Steve open it!" (his voice was probably picked up through Hugh Jackman's lapel mic.)