how to insert japanese character

Hi,

I have an user request to insert japanese character, but when i try insert into database using sqlplus it cause error and insertion failed.

Below is my database nls parameters:

PARAMETER                                       VALUE
==========                                         ===========
NLS_LANGUAGE                                AMERICAN
NLS_TERRITORY                                 AMERICA
NLS_CHARACTERSET                      WE8ISO8859P1
NLS_NCHAR_CHARACTERSET      AL16UTF16

Which table column datatype is supported for Japanese character?

Appreciate of any input given

Thanks