Heat gas or charcoal grill. In 1-quart saucepan, cook jam and vinegar over medium heat 2 to 3 minutes, stirring constantly, until jam is melted. Remove from heat; set aside.
Spray both sides of salmon pieces with cooking spray. Rub lemon-pepper seasoning salt over both sides of salmon. Place large sheet of heavy-duty foil on grill rack over medium heat. Place salmon, skin sides down, on foil. Cover grill; cook 8 to 10 minutes or until fish flakes easily with fork. Remove from heat.
Serve salmon topped with blackberry glaze and berries.