Preheat oven to 350 degrees F.
Grease a bundt cake with some butter, then dust with flour.
Mix butter and sugar with an electric mixer until blended.
Add eggs, milk, orange zest, vanilla, lemon juice, and orange juice. Mix to incorporate.
In a separate bowl, mix flour, baking soda, baking powder, and salt. Slowly pour the dry ingredients into the wet ones. Mix until thoroughly blended.
Place walnuts and raisins in a small bowl and dust with a tablespoon of flour. This will keep the walnuts and raisins from sinking to the bottom of the cake once it's cooked.
Fold the walnuts, and raisins into the batter. Pour the batter into the bundt cake pan.
Bake for one hour, or until a toothpick inserted into the center of the cake comes out clean.
Cool the cake in the pan for 15 minutes. To un-mold the cake, place a large, flat plate over the pan and flip the cake onto the plate. Cool for at least an hour before slicing.