In a bowl,whisk together the soy sauce,oyster sauce,chili paste,tomato paste,clam juice,2 tsp.of the cornstarch,the sugar,and lemon juice.Set aside.. Toss the salmon in the remaining cornstarch mixed with the chili powder.Heat a large wok until smoking.Add the peanut oil and gently stir fry the salmon,in 2 batches,until its surface is lightly browned and crisp,about 2 minutes.Remove the salmon with a slotted spoon to a strainer or colander to drai.Pour off all but a thin film of the oil. Add the scallions,garlic and ginger root and stir fry 10 seconds.Return the salmon,add the reserved liquid and simmer until lightly thickened.Toss in the pumpkin seeds.Serve over rice.Makes 4 servings...