Score skin or pork in a crisscross pattern. Combine the four spice ingredients and add the chopped herbs. Rub this mixture all over ham. Note do not salt as smoked pork is already salted. Place the leg in a roasting pan not much bigger than itself and pour Riesling wine into the pan, not over the pork.
Roast the pork for 2- 2/12 hours, or until inside temperature reads 140 degrees Fahrenheit. At the 1 ½ hour mark or when temperature reads about 100 degrees Fahrenheit , combine the pear nectar, orange zest and mustard in a small saucepan and reduce by half. Pour this mixture over ham , making sure to brush evenly over surface. Continue baking until brown and crisp and reached an internal temp of 140 degrees Fahrenheit.