Combine all ingredients in a medium saucepan. Cook on medium heat, whisking occasionally, until preserves are melted and sauce is smooth. Remove from heat. Set aside. Preheat oven to 325 degrees. Place ham on rack in a shallow roasting pan. Bake, uncovered, for 2 hours or until a meat thermometer registers 140 ºF. Liberally baste ham with glaze during the last 45 minutes of baking. Makes 2 1/4 cups of glaze.