Combine first 5 ingredients in a medium saucepan. Bring to a boil over high heat; reduce heat to medium, and cook 15 to 20 minutes or until slightly thickened, whisking often. Whisk in butter, 1 tablespoon at a time, stirring until melted. Add salt and pepper, and remove mixture from heat.
Peel and devein shrimp, leaving tails intact. Thread shrimp evenly onto 12-inch skewers. Brush with olive oil. Grill, covered with grill lid, over medium-high heat (350° to 400°), 3 minutes on each side or until shrimp turn pink. Serve grilled shrimp kebabs with sauce.