用java socket做的一个发送邮件的程序出现错误，大家给看看

Question

源码：
package mail;import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.*;public class MailTest 
{
public static void main(String args[])
{
JFrame frame=new MailTestFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}class MailTestFrame extends JFrame
{
private BufferedReader in;
private PrintWriter out;
private JTextField from;
private JTextField to;
private JTextField smtpServer;
private JTextArea message;
private JTextArea communication;
sun.misc.BASE64Encoder enc;
public static final int WIDTH=300;
public static final int HEIGHT=300;
public MailTestFrame()
{
setSize(WIDTH,HEIGHT);
setTitle("MailTest");
GridBagLayout gbag=new GridBagLayout();
getContentPane().setLayout(gbag);

GridBagConstraints gbc=new GridBagConstraints();
gbc.fill=GridBagConstraints.HORIZONTAL;
gbc.weightx=0;
gbc.weighty=0;

gbc.weightx=0;
add(new JLabel("From:"),gbc,0,0,1,1);
gbc.weightx=100;
from=new JTextField(20);
add(from,gbc,1,0,1,1);

gbc.weightx=0;
add(new JLabel("To:"),gbc,0,1,1,1);
gbc.weightx=100;
to=new JTextField(20);
add(to,gbc,1,1,1,1);

gbc.weightx=0;
add(new JLabel("SMTP server:"),gbc,0,2,1,1);
gbc.weightx=100;
smtpServer=new JTextField(20);
add(smtpServer,gbc,1,2,1,1);

gbc.fill=GridBagConstraints.BOTH;
gbc.weighty=100;
message=new JTextArea();
add(new JScrollPane(message),gbc,0,3,2,1);

communication=new JTextArea();
add(new JScrollPane(communication),gbc,0,4,2,1);

gbc.weighty=0;
JButton sendButton=new JButton("Send");
sendButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
new Thread()
{
public void run()
{
sendMail();
}
}.start();
}
});

JPanel buttonPanel=new JPanel();
buttonPanel.add(sendButton);
add(buttonPanel,gbc,0,5,2,1);
}

private void add(Component c,GridBagConstraints gbc,int x,int y,int w,int h)
{
gbc.gridx=x;
gbc.gridy=y;
gbc.gridwidth=w;
gbc.gridheight=h;
getContentPane().add(c,gbc);
}

public void sendMail()
{
try
{
Socket s=new Socket(smtpServer.getText(),25);

out=new PrintWriter(s.getOutputStream());
in=new BufferedReader(new InputStreamReader(s.getInputStream()));
String hostName=InetAddress.getLocalHost().getHostName();

receive();

send("HELO "+hostName);
receive();
send("MAIL FROM:<"+from.getText()+">");
receive();
send("RCPT TO:<"+to.getText()+">");
receive();
send("DATA");
receive();
StringTokenizer tokenizer=new StringTokenizer(message.getText(),"\n");
while(tokenizer.hasMoreTokens())
send(tokenizer.nextToken());
send(".");
s.close();
}
catch(IOException exception)
{
communication.append("Error: "+exception);
}
}

public void send(String s)throws IOException
{
communication.append(s);
communication.append("\n");
out.print(s);
out.print("\r\n");
out.flush();
}
public void receive()throws IOException
{
String line=in.readLine();
if(line!=null)
{
communication.append(line);
communication.append("\n");
}
}

}最后报错为：
MAIL FROM:<[email protected]>
553 Requested action not taken: Local user only,smtp5,wKjSjrCbPwLPH_FGubB9Ag==.26394S2 1190207440
RCPT TO:<******@126.com>
503 bad sequence of commands
DATA
354 Send from Rising mail proxy
fffff
麻烦，大家给我分析下是什么问题啊，多谢了