Place the ham in a baking dish and bake for 10 minutes per pound uncovered.
While the ham bakes, add the cranberries, riesling, sugar and honey to a small saucepan and cook over medium heat until the cranberries start to burst and break down. Stir in the mustard and orange zest and allow to cook for an additional 5 minutes over low heat until all the cranberries have broken down. Allow to cool slightly and then pour the mixture into the bowl of a food processor. Process until smooth.
When 30 minutes remains in the cooking time, brush the glaze on the ham and in between the slices using a pastry or basting brush. Finish cooking the ham and serve immediately.