Drain pineapple juice into a medium bowl; set pineapple aside. Add bananas to the juice. In a large bowl, combine cranberry sauce and sugar. Remove bananas, discarding juice, and add to cranberry mixture. Stir in pineapple, whipped topping and nuts. Pour into a 13-inch by 9-inch dish. Freeze until solid. Remove from the freezer 15 minutes before cutting.