Season ribs with pepper and place on medium-hot grill over indirect heat. Close grill hood and grill turning only occasionally, for 1 1/2 to 2 hours, until pork is very tender. (Add extra charcoal if necessary to keep grill temperature at about 325-350 degrees F.)
Meanwhile, in small bowl, stir together remaining ingredients. Baste ribs twice with sauce mixture during last 30 minutes of grilling.