In a large bowl, dissolve yeast in warm water, then add the milk, 1/2 cup of the sugar, eggs, butter, salt & 2 1/2 cups of the flour, beating until smooth. Stir in enough of the remaining flour to form a soft dough.
Turn onto a floured surface, then knead for 6 to 8 minutes or until smooth & elastic.
Place in a greased bowl, turning once to grease the top, then cover & let rise in a warm place about 1 hour or until doubled.
Grease two 9"x5" loaf pans.
Punch dough down, then divide in half. Roll each half into an 18"x8" rectangle.
In a small bowl, combine cinnamon & remaining 1/2 cup of sugar, then sprinkle this cinnamon mixture over the dough, before rolling each rectangle up from a short side. Pinch the seam to seal the dough.
Place seam side down in the prepared loaf pans, then cover them & let rise until doubled, about 1 1/2 hours.
Preheat the oven to 350 degrees F & bake the loaves for 30-35 minutes or until golden brown.