Place corn on grill rack coated with cooking spray; cook 10 minutes or until lightly browned, turning every 2 minutes. Cool. Cut kernels from ears of corn.
Bring 4 cups water to a boil in a large saucepan. Add lima beans; cook for 20 minutes. Add green beans; cook 2 minutes. Drain and rinse with cold water; drain well.
Melt butter in a large nonstick skillet over medium-high heat. Add chopped onion and garlic; cook, stirring occasionally, for 5 minutes or until onion is lightly browned. Stir in corn, and cook 2 minutes. Add beans; cook for 2 minutes. Remove from heat. Stir in tomatoes and remaining ingredients.