Problem in proxy settings

The piece of code works fine in my home.But when iam using this code in my office by setting the proxy settings it throwing error as below.
error
-------
java.net.UnknownHostException: proxynt.pune.gsslco.co.in
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at sun.net.NetworkClient.doConnect(NetworkClient.java:157)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:388)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:500)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:233)
at sun.net.www.http.HttpClient.New(HttpClient.java:306)
at sun.net.www.http.HttpClient.New(HttpClient.java:318)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:792)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:733)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:658)
at javaapplication6.NewMain.connectnet(NewMain.java:59)
at javaapplication6.NewMain.main(NewMain.java:105)
---------------

code

System.setProperty("https.proxyHost", "19.27.24.13");
System.setProperty("https.proxyPort", "83");
try
{
String urlName="http://proxynt.pune.gsslco.co.in:7890/intranet/finance/Annual_reports/annual_report_2000.pdf";
URL url = new URL(urlName);
File dat = new File("data.pdf");
FileOutputStream datStream = new FileOutputStream(dat);
URLConnection connection = url.openConnection();
String input = "username"+ ":" + "passord";
String encoding = new sun.misc.BASE64Encoder().encode (input.getBytes());

connection.setRequestProperty("Authorization", "Basic " + encoding);
connection.setDoOutput(true);
connection.connect();
-----------------------------------
[ July 02, 2007: Message edited by: viruthachalam arunachalam ]

I would imagine that the DNS used in your company doesn't publicize that server name inside of the company, because there are more direct ways of accessing that machine. Have you asked the network admin about this?

i have replaced the fuction with
SocketAddress addr = new InetSocketAddress(proxyadd,port);
Proxy proxy = new Proxy(Proxy.Type.HTTP, addr);
URLConnection connection = url.openConnection(proxy);
its working now. thanks.