Preheat over to 375ºF. Sprinkle yeast over 1/2 cup warm beer; stir in honey. Let stand 5 minutes. Stir in remaining beer and olive oil. Combine 4 cups all-purpose flour, rye flour, and salt. Beat into yeast mixture with onion and nuts to make soft dough. Knead on floured surface, adding up to one-half cup more flour, until smooth and elastic, about 10 minutes. Push stray nuts back into dough and place in oiled bowl, turning to coat. Cover; let rise until doubled. Punch dough down and divide in half. Shape into round loaves or, divide each half into thirds. Roll each third into a 12-inch long rope. Braid three together and tuck ends under. Place on baking sheet. Cover and let rise until doubled, about 1 hour. Bake at 375ºF., until crusty and browned, approximately 45 - 50 minutes. Cool.