In a bowl, combine 2 cups flour, sugar, orange zest, yeast, salt and ginger. In a saucepan, heat milk, butter and water to 120°-130°. Add to dry ingredients; beat just until moistened. Add eggs; beat on low speed for 30 seconds. Beat on high for 3 minutes. Stir in raisins. Stir in enough remaining flour to form a soft dough. Turn onto a floured surface; knead until smooth and elastic, about 6-8 minutes. Place dough in a greased bowl, turning once to grease the top. Cover and let rise in a warm place until doubled, about 1-1/4 hours.
Punch dough down. Turn onto a floured surface; knead for 1 minute. Cover and let rest 15 minutes. Divide in half. Roll each portion into a 9x7-in. oval; fold in half lengthwise. Pinch edges to seal. Place in two greased 8x4-in. loaf pans. With a sharp knife, make three 1/4-in.-deep diagonal slashes across top of each loaf. Cover and let rise until doubled, about 45 minutes.
Bake at 375° for 45-50 minutes or until golden brown. Cover loosely with foil after 20 minutes to prevent over browning. Remove from pans to wire racks to cool. For glaze, combine the sugar, orange juice and butter until smooth. Stir in walnuts. Spread over loaves.