PREHEAT grill to medium-high heat. Wrap two layers of REYNOLDS WRAP Heavy-Duty Aluminum Foil over outside of 9-inch square pan. Remove pan. Melt butter in foil pan on grill. Add vegetables; cook 10 min., stirring occasionally. Meanwhile, place sausages directly on grill grate. Grill 10 min., turning after 5 min.
ADD sausages and barbecue sauce to vegetables in pan; stir. Cook an additional 5 to 10 min. or until heated through, stirring occasionally.
SERVE in rolls.