Heat broiler. Lightly coat broiler-pan rack with cooking spray.
Alternately thread ham and pineapple onto four 12-inch metal skewers (save leftover pineapple for snacks). Place on broiler rack.
Whisk pineapple juice and mustard in bowl; baste kabobs.
Broil kabobs 3 inches from heat 6 to 10 minutes, until ham is lightly browned, turning and basting halfway through cooking. Heat remaining juice mixture; serve with kabobs.