COMBINE SHREEDE CHEESE AND FLOUR; SET ASIDE. IN A SAUCEPAN COOK GREEN PEPPER IN BUTTER TILL TENDER BUT NOT BROWN. STIR IN WINE; HEAT SLOWLY JUST TILL BUBBLING. GRADUALLY ADD SHREDDED CHEESE, STIRRING CONSTANTLY, UNTIL SMOOTH AND BUBBLY. STIR IN CREAM CHEESE AND MUSTARD; COOK AND STIR OVER LOW HEAT TILL SMOOTH. TRANSFER CHEESE MIXTURE TO FONDUE POT.