Problem with national characters on windows client

Question

Hello there,
I'am having problem with national characters on windows client.
All national data stored in NVARCHAR2 colums, applications (.net) works fine,
but in sqlplus:
select city from test_table;
- everything ok, sqlplus shows national characters
select dump(N'<national symbols>') from dual
- returns
Typ=96 Len=12: 0,191,0,191,0,191,0,191,0,191,0,191
select * from test_table where city = N'<national symbols> '
- always returns nothing
As i understand the problem in
sql query text (and national literals) convertion
to servers "WE8ISO8859P1" encoding, Is it possible
to solve the issue?
Thanks in advance
PS.
Console in right mode (chcp=1251)
sqlplus shows russian messages well
Server (oracle 9 on solaris):
select * from nls_database_parameters
NLS_NCHAR_CHARACTERSET AL16UTF16
NLS_SAVED_NCHAR_CS WE8ISO8859P1
NLS_LANGUAGE AMERICAN
NLS_TERRITORY AMERICA
NLS_CURRENCY $
NLS_ISO_CURRENCY AMERICA
NLS_NUMERIC_CHARACTERS .,
NLS_CHARACTERSET WE8ISO8859P1
NLS_CALENDAR GREGORIAN
NLS_DATE_FORMAT DD-MON-RR
NLS_DATE_LANGUAGE AMERICAN
NLS_SORT BINARY
NLS_TIME_FORMAT HH.MI.SSXFF AM
NLS_TIMESTAMP_FORMAT DD-MON-RR HH.MI.SSXFF AM
NLS_TIME_TZ_FORMAT HH.MI.SSXFF AM TZH:TZM
NLS_TIMESTAMP_TZ_FORMAT DD-MON-RR HH.MI.SSXFF AM TZH:TZM
NLS_DUAL_CURRENCY $
NLS_COMP BINARY
NLS_LENGTH_SEMANTICS BYTE
NLS_NCHAR_CONV_EXCP FALSE
NLS_RDBMS_VERSION 9.2.0.6.0
Client (windows server 2003, oracle client 10):
NLS_LANG = RUSSIAN_CIS.CL8MSWIN1251

Answer 1

N'<national symbols>', being part of an SQL statement, will be converted to the database character set (WE8ISO8859P1) before being parsed. Only if the client and the database are both 10.2 or higher, the client can encode the literal appropriately so that it survives this conversion.
In earlier versions, you can do the encoding yourself. Instead of the N'<national symbols>' literal use the UNISTR function: UNISTR('\xxxx\yyyy\zzzz'), where U+xxxx, U+yyyy, U+zzzz are Unicode code points of your national characters.
-- Sergiusz