You look to be very close. I am not going to be much help because I have not tried this. I did get a new PL/SQL book today [Oracle PL/SQL Tips & Techniques ISBN 0-07-882438-9].

There is 1 short entry on calling external procedures whcih they give the syntax on creating the wrapper procedure or function:

PROCEDURE procedure_name [(parameter_list)] AS EXTERNAL
LANGUAGE C
LIBRARY library_name
[NAME external_name]
[CALLING STANDARD {C | PASCAL}]
[WITH CONTEXT]
[PARAMETERS (external_parameter_list)];

FUNCTION function_name [(parameter_list)] RETURN
datatype AS
LANGUAGE JAVA
NAME java_signature_string;

>Thanks,
>
>But what about oracle as an external process....
>
>As indicated by the following....
>
>SQL> create or replace library GetFile AS 'C:\winnt\system32\GetFile.dll';
> 2 /
>
>Library created.
>
>SQL>
>SQL> CREATE OR REPLACE FUNCTION FGetFile(cDir CHAR)
> 2 RETURN CHAR AS EXTERNAL
> 3 LIBRARY GetFile
> 4 NAME "GetName";
> 5 /
>
>Function created.
>
>SQL> select fgetfile() from dual;
>select fgetfile() from dual
> *
>ERROR at line 1:
>ORA-06553: PLS-306: wrong number or types of arguments in call to 'FGETFILE'
>
>
>SQL> select fgetfile('ccc') from dual;
>select fgetfile('ccc') from dual
> *
>ERROR at line 1:
>ORA-06521: PL/SQL: Error mapping function
>ORA-06522: Unable to load symbol from DLL
>ORA-06512: at "LINDEX.FGETFILE", line 0
>ORA-06512: at line 1
>
>
>This error is in my experience. The same as
>DECLARE STRING GetName in 'C:\winnt\system32\GetFile.dll' as string@
>?GetName()
>
>
>So what I guage is that Oracle does not support COM in this manner.
>
>But maybe someone knows another way to sort this out.