Place barbecue sauce, 1 cup of the papayas, the mustard and cumin in blender; blend until smooth.
Pour over ribs in resealable plastic bag. Seal bag; turn to evenly coat ribs with barbecue sauce mixture. Refrigerate 4 hours to marinate, turning bag occasionally.
Remove ribs from marinade; discard bag and marinade.
Preheat grill to medium-high heat. Grill ribs 12 to 15 min. on each side or until cooked through. Shred meat with two forks.
Mix remaining 1 cup papayas, the mint and pepper; spread evenly onto tortillas. Top with meat; roll up.