Place quail eggs in a small saucepan filled with water, and bring water to a boil. Boil 30 seconds, and turn off heat. Cover. For slightly soft eggs, let eggs stand in hot water 2 1/2 minutes; for firmer eggs, let eggs stand in hot water 2 minutes more.
Prepare a bowl of cold water. Remove eggs from hot water; submerge in cold water. Let eggs stand 5 minutes. Remove from water, and remove shells.
Preheat oven to 400 degrees. Place bread on a baking sheet; toast until golden brown.
Slice eggs lengthwise; cover loosely with plastic wrap. Spread 1 teaspoon caviar on each piece of toast, top with half an egg, and garnish with 1/4 teaspoon caviar. Serve.