Perhaps this was already resolved lol, but I found this and I thought it might clear some stuff up. :]
■"In chapter 117 of the manga, when Orochimaru first performs the technique, he tries to summon a third coffin, when the coffin is not summoned, he comments on its failure. Years later, in chapter 520, Kabuto explains that Orochimaru's attempt to summon the Fourth Hokage had failed due to his soul not residing in the "pure world". In episode 69 of the anime, when Orochimaru used this jutsu, the coffin breifly appears, with "four" (四, Yon) written on it; though the summoning of the Fourth Hokage still fails. Based on Kabuto's demonstration, it would seem the actual failure would have occurred when Orochimaru preformed the original preparatory ritual."
--Narutopedia (trivia)   See 15 other replies