In food processor bowl with metal blade, combine cantaloupe flesh, lemonade concentrate and powdered sugar; process until smooth. Stir in mint. Place mixture in medium bowl; let stand at room temperature for 1 hour.
Strain mixture into 2-quart nonmetal freezer container, pressing mint with spoon to remove as much liquid as possible. Discard mint. Stir water and bourbon into melon mixture. Cover; freeze 6 to 8 hours or until icy, stirring twice.
To serve, spoon 1/2 cup frozen mixture into each glass. Add 1/2 cup ginger ale to each glass; stir gently.