Unroll cake; remove towel. Beginning at a narrow end, spread raspberry sherbet on one-third of cake, orange sherbet on next third of cake and lime sherbet on remaining cake. Roll up carefully. Place roll, seam side down, on 18x12-inch (45x30 cm) piece of foil. Wrap in foil; freeze at least 6 hours until firm. Remove from freezer 15 minutes before serving. Cut roll into 3/4-inch (2 cm) slices. Store wrapped in freezer.