Preheat oven to 325 degrees F. Remove ham from package and discard the bone guard. Place ham cut side down in baking pan and cover ham with foil. Place ham in oven and heat for approximately 15 minutes per pound until warm. Do not overcook.
To Glaze Ham: In small saucepan, combine orange marmalade, bourbon, maple syrup and mustard. Cool over medium heat, stirring occasionally, until marmalade is melted. Thirty minutes before ham is done, spoon glaze over ham. Continue baking. Serve ham with remaining glaze.