Mix together warm milk and yeast in a small bowl and set aside.
In the bowl of a stand mixer fitted with a dough hook add flour, salt, sugar and stir to combine.
Mix in eggs, margarine and yeast milk on low until a loose dough forms.
Gradually increase speed to medium until dough begins to climb the hook. Add a little flour if it seems too sticky.
When you have a dough ball, remove it from bowl, grease another lg bowl, set the dough ball in & cover lightly in a warm place about 1 hour.
After the dough has doubled in size turn it out onto a lightly floured surface, cover and let rest for 10 minutes.
In a small bowl, combine brown sugar and cinnamon.
Roll dough into a 16x21 inch rectangle. Spread dough with 1/3 cup butter and sprinkle evenly with sugar/cinnamon mixture. Roll up dough and cut into 12 rolls. Place rolls in a lightly greased 9x13 inch baking pan. Cover and let rise.
If you are making these the evening before store in the refrigerator overnight. (remove and let warm to room temperature 30 minutes before baking)
If you want to cook these ASAP cover and let rise ina warm place until nearly doubled in volume, about 30 minutes.
When ready to cook preheat oven to 375 degrees F (200 degrees C).
Bake rolls in preheated oven until golden brown, about 15-20 minutes.
Meanwhile, beat together cream cheese, 1/4 cup butter, confectioners' sugar, vanilla extract and salt.
When you remove the rolls from the oven immediately invert them onto a cookie sheet to allow the cinnamon drippings to re-coat the rolls. Let rest for 5 minutes
Turn pan back over and spread frosting on warm rolls before serving.