In a large mixing bowl stir together starter and water. Mix in half of white flour and half of rye flour, one cup at a time, and salt. Stir in currants, remaining rye flour and enough of white flour to make a stiff dough. When dough is too stiff to stir, turn out onto work surface. Knead until it comes together in a mass, about 8 minutes; dough will still be slightly sticky. Transfer to a clean mixing bowl, cover and set aside until doubled in size.
Turn out dough on lightly-floured work surface and punch down with floured hands. Knead briefly and divide in two. Roll each half into a log about 3 inches in diameter; cut each into 12 rolls. Using palm of your hand roll each piece of dough into a small, tight round roll. Place rolls, about 2 inches apart, on a cornmeal-dusted baking sheet. Cover and set aside to rise, until barely doubled. Preheat oven to 450 degrees. Bake for 30 minutes. For crusty rolls, spray walls of oven with water with a plant mister.
Yield: 2 dozen rolls