1.In a small bowl, combine carrot, celery, cabbage, sauce, sugar and juice.
2.Dip each sheet of rice paper in a medium bowl of warm water until just softened; lift sheet carefully from water, placing on a tea-towel-covered board with a corner pointing towards you. Place 1 level tbsp of the vegetable mixture horizontally in centre of sheet; top with 1 mint leaf. Fold corner facing you over filling; roll rice paper to enclose filling, folding in sides after first complete turn of roll. Repeat with remaining rice paper sheets, vegetable mixture and mint leaves.