To prepare catfish: Sprinkle fillets with garlic, salt and pepper.
Spray grill basket or rack with nonstick cooking spray.
Grill fish uncovered directly over medium-hot coals about 5 minutes per side, or until fish flakes easily.
To prepare relish: In medium saucepan cook onion, celery, carrot, garlic and jalapeno peppers in margarine until onion is tender.
Stir in black beans, ham, cilantro and salt.
Bring to boil; reduce heat and simmer, uncovered, 10 minutes or until desired consistency.