Preheat oven to 375 degrees. Sift flour and sugar, set aside. In a saucepan, bring the margarine, cocoa and water to a boil; remove from heat. In a large bowl, mix all remaining cake ingredients. Add the flour mixture and cocoa mixture, stirring well. Bake in a greased and floured 9x13" pan for 20 to 30 minutes. Check for doneness with a clean toothpick. Ten minutes into the baking of the cake, prepare the frosting. Place the margarine, cocoa, and milk in a saucepan and bring to a boil. Remove from the heat and add the remaining ingredients. Beat until smooth. FROST THE CAKE AS SOON AS IT COME OUT OF THE OVEN. Let it cool a little before cutting, if you can't possible hold out!. This cake is so good, you'd eat it with one foot in the fire if you had to. ----