Melt Butter Or Margarine In A Large Saucepan Over Medium Heat. Add The Worcestershire Sauce, Lemon Juice, Sugar, Paprika, Salt And Cayenne Pepper. Mix Together And Bring Mixture To A Boil, Stirring Often. Add The Cooked Pork And Let Simmer Just Until Pork Is Heated Through. Divide Into 4 Equal Portions Onto The Bottom Of Each Hamburger Bun.