大虾帮帮忙呀，JavaMail收取邮件时主题是乱码

import javax.mail.*;
import javax.mail.internet.*;
import java.util.*;
import java.io.*;public class MailReceiver {
    public MailReceiver() {
    }
    
    public static void printMessages(Message msgs[]) {
     try {
      for (int msgIdx = 0; msgIdx < msgs.length; ++msgIdx) {
       String from = ((InternetAddress)msgs[msgIdx].getFrom()[0]).getPersonal();
       if (from == null)
         from = ((InternetAddress)msgs[msgIdx].getFrom()[0]).getAddress();
       System.out.println("From: " + from);       String subject = msgs[msgIdx].getSubject();
       System.out.println("Subject: " + subject);       System.out.println("---------------------------------------------------------");
      }
     } catch (Exception ex) {
      ex.printStackTrace();
     }
    }    public static void receive(String popServer, String popUser, String popPassword) {
     Store store = null;
     Folder folder = null;
     
     try {
      Properties props = System.getProperties();
      Session session = Session.getDefaultInstance(props, null);
      store = session.getStore("pop3");
      store.connect(popServer, popUser, popPassword);
      folder = store.getDefaultFolder();
      if (folder == null)
       throw new Exception("No default folder");
      folder = folder.getFolder("INBOX");
      if (folder == null)
       throw new Exception("No POP3 INBOX");
      folder.open(Folder.READ_ONLY);
      Message []msgs = folder.getMessages();   printMessages(msgs);
     } catch (Exception ex) {
      ex.printStackTrace();
     } finally {
      try {
       if (folder != null)
        folder.close(false);
       if (store != null)
        store.close();
      } catch (Exception ex2) {
       ex2.printStackTrace();
      }
     }
    }    public static void main(String args[]) {
     try {
      String popServer = "...............";
      String popUser = ".............";
      String popPassword = ".............";
      receive(popServer, popUser, popPassword);
     } catch(Exception ex) {
      ex.printStackTrace();
     }
    }
}我用我的邮箱试了下，结果输出的内容是这样子的：
From: [email protected]
Subject: =?gb2312?Q?DreamSpark-=CE=A2=C8=ED=D1=A7=C9=FA=C8=ED=BC=FE=D7=CA=D4=B4 =D1=A7=C9=FA=C9=ED=B7=DD=D1=E9=D6=A4?=
---------------------------------------------------------
From: Liang Alei
Subject: Re: ??????
---------------------------------------------------------
From: zhengdeen
Subject: Re: ??????
---------------------------------------------------------
From: zhengdeen
Subject: Re: Re: ??????
---------------------------------------------------------
From: HeYJ
Subject: Re: ??????????????
---------------------------------------------------------
From: HeYJ
Subject: 
---------------------------------------------------------
From: HeYJ
Subject: Re: 
---------------------------------------------------------
From: HeYJ
Subject: Re: Re:
---------------------------------------------------------
From: [email protected]
Subject: Re: ??? 5080379063
---------------------------------------------------------
From: ???
Subject: ??? ????
---------------------------------------------------------
From: ???
Subject: ??? ????
---------------------------------------------------------
From: ???
Subject: Re: ??? ????
---------------------------------------------------------
From: ???
Subject: Re: Re: ??? ????
---------------------------------------------------------
麻烦高手帮我改下代码啦，我是Java新手的，第一次用，不知道怎么弄，先谢谢了~·