Clean the soft shell crabs by cutting away the eyes and mouth. Lift up the top side flaps and pull out the feathery gills. Turn the crab over and fold back the tail flap, also called the apron, and pull away from the body and discard. Place crabs in a shallow dish and add enough milk to cover. Soak crabs in milk for 10 to 15 minutes hour. Slice ham into julienne. Heat pan over high heat with oil. Season flour. Dip crabs in flour, and shake off excess. Saute crabs in hot pan on both sides. Transfer crabs onto baking sheet and place in oven to keep warm.
Pour off fat from skillet. Add 1 tablespoon butter to pan. Add shallots and garlic and saute for 2 minutes. Add julienne strips to skillet and saute for 1 minute. Add tomatoes and white wine and reduce. Whisk in butter and chives, salt and pepper, to taste. Serve sauce over crabs.