Combine milk, flour, and eggs in a blender and process until smooth, scraping down the sides as needed.

Refrigerate the batter, covered, for 1 hour.

Heat an 8-inch nonstick crepe pan or skillet.

Brush 1/8 of the melted margarine over the bottom of the pan.

Pour in 1/8 of the batter (about 1/4 cup), quickly swirling to cover the entire bottom of the pan.

Cook until the bottom of the blintze wrap is lightly browned.

Carefully turn the wrap over using a pancake turner and brown the other side.

Slide the blintze wrap onto a plate.

Repeat the procedure 7 more times, using the remaining batter and melted margarine to make 7 more blintz wraps.

Combine the cream cheese, egg, and sugar, stirring until thoroughly blended.

Fold in the blueberries and cinnamon.

Spoon 1/8 of the filling onto the center of each blintz wrap.

Fold the sides of the wrap in and roll to enclose the filling.

In a small bowl, combine the sour cream and vanilla, stirring until smooth.

Fold in the remaining blueberries.

Spoon the sauce over the blintzes.

Serve immediately.