1. Preheat broiler. Combine first 5 ingredients in a large bowl. Stir in celery, onion, and lobster meat. Season with salt and black pepper to taste.
2. Cut wedges out of center of bread. Spread with butter, and broil 1 minute or until toasted.
3. Divide lobster mixture among rolls; sprinkle with cayenne pepper. Garnish, if desired.