Peel and devein shrimp; set aside.
Coat a large nonstick skillet with cooking spray; add margarine. Place over medium-high heat until margarine melts. Add onion; saute until tender. Stir in jalapeno pepper, gingerroot, and garlic; saute 2 minutes. Add curry powder; saute 2 minutes. Add tomato; cook over medium heat 5 minutes or until slightly thickened, stirring frequently. Stir in yogurt, salt, and white pepper. Add shrimp; bring to a boil. Reduce heat, and simmer 5 minutes or until shrimp turn pink.
Place rice on a serving platter; spoon shrimp mixture over rice. Sprinkle with green onions and parsley. Serve immediately.