retrieve data in PL/SQL proc using JDBC in Websphere

[jso113]

I am trying to retrieve a list of address locations from our database based on a user id and account number. I keep getting an ORA-06550 error.
Here is my package spec:

type location_array is table of varchar2(510) Index By Binary_Integer;
FUNCTION getlocations
(
 userid in varchar2,
 accountno in number,
 user_loc in out location_array,
 delimiter in out varchar2
 )
 RETURN number

Here is a code snippet from my test class (I have already created my connection, that part has tested successfully with other PL/SQL procs):

String userId = "someuser";
int accountNo = 9999999;
CallableStatement stmt = conn.prepareCall("{? = call PKGTEST.getlocations(?,?,?,?)}");
stmt.registerOutParameter(1, Types.INTEGER);
stmt.registerOutParameter(4, Types.ARRAY);
stmt.registerOutParameter(5, Types.VARCHAR);
stmt.setString(2, userId);
stmt.setInt(3, accountNo);
stmt.execute();
String result = String.valueOf(stmt.getInt(1));
System.out.println("result is: " + result);

Any help would be most appreciated! Thanks in advance!

[SJ Adnams]

I have not looked up the error code, but I guess it is something to do with the ARRAY.
see the thomas kyte website on how to do this correctly - or I think i posted an example in the oracle forum a few months ago..