Database Software

Hi, I'm having a problem inserting utf8 data into utf8 nvarchar column

We are on oracle db 11gR2 (11.2.0.3.0)
Our db characterset is WE8MSWIN1252
Our nchar db characterset is UTF8

I created a Nvarchar2 column but I am unable to insert utf8 characters into this column from sql or plsql without losing most of the characters to upside down question marks. I can copy paste directly into say Toad and save without issues.

Here is an example of my problem:

select * from nls_database_parameters;

NLS_LANGUAGE AMERICAN
NLS_TERRITORY AMERICA
NLS_CURRENCY $
NLS_ISO_CURRENCY AMERICA
NLS_NUMERIC_CHARACTERS .,
NLS_CHARACTERSET WE8MSWIN1252
NLS_CALENDAR GREGORIAN
NLS_DATE_FORMAT DD-MON-RR
NLS_DATE_LANGUAGE AMERICAN
NLS_SORT BINARY
NLS_TIME_FORMAT HH.MI.SSXFF AM
NLS_NCHAR_CHARACTERSET UTF8
NLS_TIMESTAMP_FORMAT DD-MON-RR HH.MI.SSXFF AM
NLS_TIME_TZ_FORMAT HH.MI.SSXFF AM TZR
NLS_TIMESTAMP_TZ_FORMAT DD-MON-RR HH.MI.SSXFF AM TZR
NLS_DUAL_CURRENCY $
NLS_COMP BINARY
NLS_LENGTH_SEMANTICS BYTE
NLS_NCHAR_CONV_EXCP FALSE
NLS_RDBMS_VERSION 11.2.0.3.0

create table test_nchar (my_col nvarchar2(100));
insert into test_nchar (my_col) values ('£ ¢ ¥ € ½ ½ ¼ ¾ ⅜ Å ( Å κ ε ω θ ρ Ω µ Ω Δ ∑ π α τ βγδΣΥηλξφρσψΔÅ');
select * from test_nchar gives:
£ ¢ ¥ € ½ ½ ¼ ¾ ¿ Å ( Å ¿ e ¿ ¿ ¿ O µ O ¿ ¿ p a t ß¿dS¿¿¿¿f¿s¿¿Å

Thinking it might be a client bug I created a database procedure to update the table

create or replace procedure test_update_utf8 as
begin
update test_nchar
set my_col = to_char(sysdate,'dd/mm/yyyy hhmiss')||to_nchar('£ ¢ ¥ € ½ ½ ¼ ¾ ⅜ Å ( Å κ ε ω θ ρ Ω µ Ω Δ ∑ π α τ βγδΣΥηλξφρσψΔÅ');
end;
/

select * from test_nchar gives:
16/05/2013 114803£ ¢ ¥ € ½ ½ ¼ ¾ ¿ Å ( Å ¿ e ¿ ¿ ¿ O µ O ¿ ¿ p a t ß¿dS¿¿¿¿f¿s¿¿Å

I created a database job that calls the procedure but still get the same result.

Why can I not insert utf8 characters into an utf8 defined column?

Thanks

Dave