Place ham fat side down in a shallow pan. Pour cola into pan 1/2 inch deep. Bake 2 to 3 hours, or until ham can easily be pierced with a fork, basting with cola every 15 minutes. Center of ham will read 140 degrees F (60 degrees C) on a meat thermometer. Remove ham from pan and cool.
Increase oven temperature to 375 degrees F (190 degrees C).
Cut away the rind with a sharp knife. Combine sugar, mustard, bread crumbs and enough cola to form a thick paste. Spread paste over entire ham. Place ham on roasting rack in oven and bake 45 minutes longer, basting every 10 minutes, until mustard paste has melted into a dark glaze. Let stand at room temperature 30 minutes before slicing.