Creamy Crockpot Chicken

6 boneless, skinless chicken breast halves
1/4 cup butter
1.7oz env. Italian dressing mix
1 8 oz pkg cream cheese
1 can cream of chicken soup
Hot, cooked rice

Place chicken and butter in slow-cooker.  Sprinkle with Italian dressing mix. Cover and cook on LOW for 3-4 hours. When ready to serve, add cream cheese and soup. Stir in until creamy. Serve over rice.