Preheat oven to 400 degree F. Line a baking sheet with foil; lightly grease foil. Unroll pizza dough. On a lightly floured surface, roll or pat dough into a 15x10-inch rectangle. Cut dough in half crosswise and lengthwise to make 4 rectangles. Spread mustard over rectangles. Divide half of the cheese among rectangles, placing cheese on half of each rectangle and cutting or tearing to fit as necessary. Top with ham and sprinkle with caraway seeds. Top with remaining cheese. Brush edges with water. For each calzone, fold dough over filling to opposite edge, stretching slightly if necessary. Seal edges with the tines of a fork.
Place calzones on the prepared baking sheet. Prick tops to allow steam to escape. Bake in preheated oven about 15 minutes or until golden. Let stand for 5 minutes before serving. Makes 4 servings.