Heat oven to 325°F.
In small bowl, stir all ingredients except lamb until well mixed.
Place lamb in shallow roasting pan (keep netting or string on lamb). Spread herb mixture over entire surface of lamb. Insert meat thermometer so tip is in thickest part of lamb and does not rest in fat.
Roast uncovered 2 hours 5 minutes to 2 hours 15 minutes for medium-rare or until thermometer reads 140°F. (For medium doneness, bake until thermometer reads 155°F.)
Remove from oven; cover loosely with aluminum foil. Let stand 15 to 20 minutes or until thermometer reads 145°F (or 160°F for medium doneness). Remove netting or string before serving. Serve with pan juices if desired.