java parallel port program bugs

hi.could anyone please tell me what is wrong with my code given below?
the port data outputs are supposed to be made low on running the
code.but i checked the output using a digital voltmeter and it is
staying high.i am using windows XP and jdk1.5.0.and the Rxtx package
do i need to install any drivers to allow port communication?.it is
showing the IOEXCEPTION:'the data was written successfully in the
writebyte'.

package parallelIO;
import gnu.io.*;
import java.io.*;

public class ParallelIO {

    private static OutputStream outputStream;
    private static ParallelPort parallelPort;
    private static CommPortIdentifier port;

    public static final String PARALLEL_PORT = "LPT1";
    public ParallelIO()
     {
       try {
             // get the parallel port connected to the output
                      port =
CommPortIdentifier.getPortIdentifier(PARALLEL_PORT);
        // open the parallel port -- open(App name, timeout)
             parallelPort = (ParallelPort) port.open("Automator",
50);
             outputStream = parallelPort.getOutputStream();

                      byte x=5;
        outputStream.write(x);
                 outputStream.flush();
                      outputStream.close();

                }
             catch (NoSuchPortException nspe)
              {
             System.out.println("\nPrinter Port LPT1 not found :
"
                    + "NoSuchPortException.\nException:\n" + nspe +
"\n");
                }
              catch (PortInUseException piue)
                {
             System.out.println("\nPrinter Port LPT1 is in use : "
                    + "PortInUseException.\nException:\n" + piue +
"\n");
                }
              catch (IOException ioe)
               {
             System.out.println("\nPrinter Port LPT1 failed to
write : "
                    + "IOException.\nException:\n" + ioe + "\n");
                }
              catch (Exception e)
               {
             System.out.println("\nFailed to open Printer Port LPT1
with exception : "
                      + e + "\n");
                }
              finally
               {
                     if (port != null && port.isCurrentlyOwned())
                      {
                             parallelPort.close();
                         }
                     System.out.println("Closed all resources.\n");
                }
    }
}