Arrange chicken thighs in a shallow glass dish. Whisk together all remaining ingredients in a small bowl and pour over chicken. Turn pieces to coat both sides with marinade. Cover with plastic wrap and marinate in refrigerator for at least 4 hours or over night. Preheat grill to medium setting. Remove chicken from marinade and place on a grill rack that has been lightly brushed with oil. Grill thighs for about 10 minutes per side. Be careful not to burn them.