In medium microwavable bowl, stir together butter, mustard, rosemary, salt, pepper and beer. Microwave uncovered on High 1 to 1 1/2 minutes, stirring after 30 seconds, until well mixed. Brush about 1/3 of mixture evenly over surface of turkey. Fasten drumsticks together with cotton string. Insert ovenproof meat thermometer so tip is in thickest part of inside thigh and does not touch bone.