Preheat oven to 350°F.
Bring a small pot or kettle of water to a boil. Place currants into a small bowl and cover with boiling water to reconstitute. Let stand until softened and plump, then drain. If using whisky, soak currants in whisky for about an hour. Drain and reserve.
In a large mixing bowl, combine the flour, sugar, baking powder, salt and baking soda. Add the butter; use your hands to incorporate it into the flour mixture into large-sized crumbs. Mix in reconstituted currants, caraway seeds and orange zest.
In a medium mixing bowl, whisk together buttermilk and eggs, and add to dry mixture. Using a wooden spoon, stir the dough until incorporated, making sure not to over-mix.