In medium bowl, combine apple juice, soy sauce, mustard, ginger and garlic, mixing well. Pour over chicken, turning to coat. Let stand at room temperature 15 minutes to marinate.
Remove chicken to a plate. Place the marinade in a small saucepan and cook over medium heat for 3-5 minutes until hot through.
Place chicken on an oil greased medium-high grill. Cook 30 minutes or until chicken is done, turning and basting with reserve marinade.
Serve chicken over salad or on a bed of rice.