StoredProcedure returns 'Unassigned'

After SP execution, the value retorned is just 'Unassigned'. I can see in Oracle that the procedure run with no problem, but the TestComplete command "procedureObj.Parameters.Items(5).Value" returns just 'Unassigned' when should returned 'OK', as like Oracle run. I'm using this:

procedureObj.Parameters.AddParameter();
procedureObj.Parameters.Items(5).name := 'RESULT';
procedureObj.Parameters.Items(5).DataType := ftString;
procedureObj.Parameters.Items(5).Direction := pdReturnValue;
procedureObj.Parameters.Items(5).Value := nil;

PS: DB Oracle 10, but ODBC connection Oracle 12.