Melt butter in medium saucepan. Add onion and garlic; cook until onion is soft. Add sauces, mustard, chutney, allspice, salt and pepper, stir well; simmer, covered, 5 minutes. Preheat oven to moderate. Place chicken, skin-side up, in oiled baking dish; pour sauce mixture over top, completely covering chicken with mixture. Bake chicken, uncovered, in moderate oven 45 minutes, occasionally basting chicken with juices. Serve with a tomato and chickpea salad, if desired