Call DLL from PL-SQL block

Question

Hello all,
I want to call a function located in an external DLL from a PL-SQL block. I execute the followin steps :
1. Create a database library pointing to the external DLL :
create or replace library libstk as 'C:\SUMMIT\libstkdte_s_trade1.dll'
2. Create the definition and the body package :
CREATE OR REPLACE PACKAGE dllcall IS
     FUNCTION s_trade (
          s_in VARCHAR2 )
RETURN VARCHAR2;
PRAGMA RESTRICT_REFERENCES(s_trade, WNDS);
end dllcall;
show errors
CREATE OR REPLACE PACKAGE BODY dllcall IS
FUNCTION s_trade (s_in IN VARCHAR2) RETURN VARCHAR2
IS EXTERNAL
NAME "s_trade"
LIBRARY libstk
PARAMETERS (s_in           STRING,
RETURN STRING);
END dllcall;
show errors
set serveroutput on
3. Start the PL-SQL block calling the external function. And I got the foolowing error :
1 begin
2 dbms_output.put_line ( dllcall.s_trade ( '<Request> ' ||
3 '<CurveId>MYCURVE</CurveId> ' ||
4 '<Mode>02</Mode> ' ||
5 '<ExpCcy>GBP</ExpCcy> ' ||
6 '<AsOfDate>20001023</AsOfDate> ' ||
7 '<Entity>***SUMMIT-XML***</Entity> ' ||
8 '</Request>') );
9* end;
10
11 /
begin
ERROR à la ligne 1 :
ORA-06520: PL/SQL: Error loading external library
ORA-06522: Unable to load DLL
ORA-06512: at "V31.DLLCALL", line 0
ORA-06512: at line 2
The "Read - Execute permissions" of the DLL file was given to "Authentified users" .
What's wrong ?
TIA
PS : NT2K environment, DB 8.1.7
R. Charles Emile

Answer 1

Yes, a RPC was set up.
Listner.ora
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = Server1)(PORT = 1521))
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = NMP)(SERVER = Server1)(PIPE = ORAPIPE))
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = E:\Oracle\Ora81)
(PROGRAM = extproc)
tnsnames.ora
extproc_connection_data =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
(CONNECT_DATA = (SID = PLSExtProc))
Thanks
RCE