Preheat oven to 300°. Place rack in shallow roasting pan. Place ham on rack; reserve glaze packet for another use. Let ham stand at room temperature for 20 minutes.

Meanwhile, for sauce, combine jam, pineapple juice and mustard in a small saucepan. Bring to a boil; reduce heat to medium-low. Cook for 4 to 6 minutes or until coats back of spoon, stirring frequently. Remove from heat; stir in horseradish and 1 tablespoon lime zest.

Cover ham tightly with foil. Bake for 2 hours to 2 hours 50 minutes or until ham reaches 140°, uncovering ham and brushing on ½ cup of the sauce during the last 20 minutes of baking.

Transfer ham to a serving platter. Loosely cover with foil and let stand for 20 minutes. Brush with ¼ cup sauce before serving. Garnish with additional lime zest, if desired. Serve with remaining sauce.