Could a homeless drug addict really be a reliable witness in a murder trial? Amanda Knox's family and defense team were pleased Saturday during the appeal trial of her murder conviction, when the prosecutor's key witness Antonio Curatolo gave a contradictory testimony. The homeless man who lives in Perugia, not far from where Meredith Kercher was murdered, helped sway the jury at an earlier hearing, but on Saturday he mixed up dates and seemed confused. "The two youngsters were talking intensely to each other," Curatolo said, adding, "I can remember that in the piazza that night young people in masks were coming and going and buses were leaving for the nightclubs." Knox's lawyers immediately pointed out the contradiction in his testimony, saying that Kercher was killed on November 1, a day after the city of Perugia was buzzing with Halloween partygoers, and that former witnesses had said all clubs were closed on November 1. The court will reconvene on May 21 to hear updated forensic reports on previous DNA tests on the alleged murder weapon.