Score the ham in a diamond pattern, and stud the center of each diamond with a clove. (If you are using a spiral ham, you may skip this step).
Arrange a rack in the bottom ⅓ of the oven, and preheat the oven to 325°F.
Place the ham on a roasting rack in a shallow roasting pan.
Insert a probe thermometer or regular meat thermometer into the meat, and roast until the internal temperature is 130° F.
Meanwhile, combine all the glaze ingredients in a saucepan. Leave out the ground cloves if you've studded your ham with whole cloves.
Bring to a boil over medium heat, stirring constantly until thickened and bubbly. Keep stirring, and let the glaze boil for about two minutes.
When the ham reaches 125°F, remove from the oven and brush with a thick layer of glaze. Continue roasting until the internal temperature is 135°F.
Brush on some more glaze and place the ham under the broiler for a few minutes, until the glaze is nice and bubbly. Watch carefully so it doesn't burn.
Remove the ham from the oven and let rest for about fifteen minutes before serving. If there is glaze left over, drizzle it over slices before serving, or pass it at the table. In fact, you might want to double the glaze recipe to make sure you have enough!