Pineapple Glazed Ham

1 (14 pound) boneless smoked ham
1 medium-size fresh pineapple, peeled and cored and cut into rings
One small jar marinated cherries
1 pound brown sugar
1 pound box cornstarch
46-ounce can pineapple juice

Preheat oven to 350 degrees F.

Place ham on rack over pan containing 1 inch of water. Bake ham, fatty side up, at 350 degrees F for 2 hours. (Water will catch ham juices. Add more water during cooking as it evaporates; don