1. Combine first 6 ingredients in a large zip-top plastic bag. Add lamb; seal bag, and marinate in refrigerator 3 hours, turning occasionally.
2. Prepare grill.
3. Remove lamb from bag, reserving marinade. Pour marinade into a 2-cup glass measure, and microwave at HIGH 1 minute or until boiling; cook 1 additional minute.
4. Place lamb on grill rack; grill 4 to 5 minutes on each side or until lamb is done, basting occasionally with reserved marinade.