Sift together the flour and these dry ingredients: soda through cloves. Set aside.
Using an electric mixer, cream together the butter, shortening and sugar until fluffy. Add the eggs and beat until mixture is light in color, then add the buttermilk.
Stir the dry ingredients ito the butter mixture. Fold in the oats, raisins, walnuts and vanilla, blending well.
Drop by rounded teaspoons onto greased cookie sheets. Bake for 12 to15 minutes.
Meanwhile, make the icing: In a small saucepan, heat the butter over medium heat until golden brown, stirring occasionally. Remove from heat; stir in the powdered sugar and vanilla. Stir in enough water to make an icing of drizzling consistency and drizzle over warm cookies.