PayPal IPN Script Problem

[jspal]

I have not been able to get this 'PayPal tested' script to work.

Has anyone been sucessful???

<%@ page import="java.util.*" %>
<%@ page import="java.net.*" %>
<%@ page import="java.io.*" %>

<%
// read post from PayPal system and add 'cmd'
Enumeration en = request.getParameterNames();
String str = "cmd=_notify-validate";
while(en.hasMoreElements()){
String paramName = (String)en.nextElement();
String paramValue = request.getParameter(paramName);
str = str + "&" + paramName + "=" + URLEncoder.encode(paramValue);
}

// post back to PayPal system to validate
// NOTE: change http: to https: in the following URL to verify using SSL (for increased security).
// using HTTPS requires either Java 1.4 or greater, or Java Secure Socket Extension (JSSE)
// and configured for older versions.
URL u = new URL("http://www.paypal.com/cgi-bin/webscr");
URLConnection uc = u.openConnection();
uc.setDoOutput(true);
uc.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
PrintWriter pw = new PrintWriter(uc.getOutputStream());
pw.println(str);
pw.close();

BufferedReader in = new BufferedReader(
new InputStreamReader(uc.getInputStream()));
String res = in.readLine();
in.close();

// assign posted variables to local variables
String itemName = request.getParameter("item_name");
String itemNumber = request.getParameter("item_number");
String paymentStatus = request.getParameter("payment_status");
String paymentAmount = request.getParameter("mc_gross");
String paymentCurrency = request.getParameter("mc_currency");
String txnId = request.getParameter("txn_id");
String receiverEmail = request.getParameter("receiver_email");
String payerEmail = request.getParameter("payer_email");

check notification validation
if(res.equals("VERIFIED")) {
// check that paymentStatus=Completed
// check that txnId has not been previously processed
// check that receiverEmail is your Primary PayPal email
// check that paymentAmount/paymentCurrency are correct
// process payment
}
else if(res.equals("INVALID")) {
// log for investigation
}
else {
// error
}
%>

[jspal]

I can not get an answer from PayPal.

Is there anyony that can H E L P ?????