MonthNumberIndex := "1" : "2" : "3" : "4" : "5" : "6" : "7" : "8" : "9" : "10" : "11" : "12";
EndOfMonth := "31" : "28" : "31" : "30" : "31" : "30" : "31" : "31" : "30" : "31" : "30" : "31" ;
MonthName := @Replace(MONTHFIELDVALUE; MonthNumberIndex; EndOfMonth);
MonthName