In a medium bowl combine the melted butter/margarine, honey, mustard, curry powder and cayenne powder. Mix well. Place chicken breasts in a 9x13 inch baking dish and pour honey/mustard mixture over chicken. Cover and place in refrigerator. Marinate for at least 4 hours or overnight.
Preheat oven to 375 degrees F (190 degrees C).
Remove dish from refrigerator and bake, covered, in the preheated oven for 10 minutes. Remove cover and bake about 10 minutes more, or until done and juices run clear (baking time will depend a little on how thick your chicken breasts are).