Place eggplant slices in a large self-sealing plastic bag. Drizzle 3 tablespoons of the olive oil over slices and sprinkle with the 1/2 teaspoon salt. Seal; shaking bag gently to coat slices; set aside.
Meanwhile, brush remaining 1 tablespoon olive oil over meat. Season with salt and pepper. In a small bowl stir together hoisin sauce and merlot; set aside.
For a charcoal grill, cook steaks on the rack of an uncovered grill directly over medium coals for 11 to 15 minutes for medium-rare (145 degrees F) or 14 to 18 minutes for medium (160 degrees F), turning once and brushing steaks with the hoisin mixture the last 5 minutes of grilling. Place eggplant alongside steaks, grilling for 12 minutes, or until eggplant is tender, turning once. For a gas grill, preheat grill. Reduce heat to medium. Cover and grill as directed above.
Serve steak with eggplant slices. Makes 6 servings.