Remove giblets from hens; reserve for other uses. Rinse hens with cold water, and pat dry; sprinkle salt and pepper over surfaces and inside cavities.
Combine next 9 ingredients, stirring well. Cut oysters into quarters; add to breadcrumb mixture. Stir until well combined. Stuff hens lightly with oyster mixture. Close cavities, and secure with wooden picks; truss. Place hens, breast side up, in a shallow roasting pan.
Brush hens with butter, reserving any remaining butter for basting. Bake at 350° for 1 hour and 20 minutes, basting frequently.