Pour the hot water over the dates and let stand until the rest of the batter is mixed.
Beat eggs until frothy. Add the sugar and salt a little at a time, and blend well.
Mix nuts with flour and add to egg mixture, stirring well.
Combine baking soda and baking powder with the softened butter and blend with previously mixed ingredients.
Add the hot coffee, vanilla and dates, including any liquid which may remain from the soaking.
Pour into a greased tube pan and bake 1 hour in a preheated 350° oven.