Preheat oven to 350 degrees.
Grease and flour two 9 inch pans.
Stir the boiling water into the cocoa powder, and set aside to cool.
In a separate bowl, sift together the cake flour, baking soda, baking powder, cinnamon and salt.
In a medium bowl, cream together the margarine and the granular sucrolose until light and fluffy.
Beat in the vanilla, the cold water, and the cooled cocoa mixture.
In a large glass or metal mixing bowl, beat egg whites until foamy.
Gradually add the cream of tartar and sugar, continuing to beat until stiff peaks form.
Fold 1/3 of the whites into the batter, then quickly fold in remaining whites until no streaks remain.
Pour batter into prepared pans.
Bake in the preheated oven for 30 to 35 minutes, or until a toothpick inserted into the center of the cake comes out clean.