Oracle Forms 6i Problems After Alter Database From We8iso8859p1 To Ar8mswin1256

i have oracle froms  6i application with database characterset WE8ISO8859P1 after alter database to AR8MSWIN1256 the lables and text and menus on forms and reports become ?????????? and after chage nls_lang from WE8ISO8859P1 to AR8MSWIN1256 on then client and i do this alter to  can   build ADF pages on the same data base .

can any one help me to solve this problems or change lable and text manualy and it will be hard