JavaMail Encoding Setting

When i send the email in english, it has no problem.
But when i send in chinese, and i check the email in the outlook
express, i cannot see the chinese code, it needs me to set the
encoding in outlook express. For example, if it is chinese
traditional, i need choose chinese traditional to see it. If it is
simple chinese, it needs me to change to gb2312(simple chinese)
is there any method i can set when i send the email in my program, the
receiver can see it directly without his configuration?
Below is my code:

public boolean SendEmail(String EmailTo, String subject, String
Content, String MailServer, String arg_sEncoding)
    {
        boolean Rtr = false;
        String mailhost=MailServer;
                    boolean debug =false;
                    String mailer = "msgsend";
                    String Emailfrom = EmailTo;
        try
        {
            if(arg_sEncoding != null && !arg_sEncoding.equals(""))
            {
                arg_sEncoding = arg_sEncoding.trim();
            }
            else
            {
                arg_sEncoding = "en";
            }
            if(arg_sEncoding.toLowerCase().equals("en"))
            {
                arg_sEncoding = "ISO8859_1";
            }else if(arg_sEncoding.toLowerCase().equals("zh_tw"))
            {
                arg_sEncoding = "MS950";
            }else if(arg_sEncoding.toLowerCase().equals("zh_cn"))
            {
                arg_sEncoding = "GB2312";
            }
            if(!arg_sEncoding.toLowerCase().equals("ISO8859_1")
                && !arg_sEncoding.toLowerCase().equals("MS950")
                && !arg_sEncoding.toLowerCase().equals("GB2312"))
            {
                arg_sEncoding = "MS950";
            }
            Util.debugLog("In CQQPWebSendEmail -
arg_sEncoding:"+arg_sEncoding);
         Properties props = System.getProperties();
            // XXX - could use Session.getTransport() and
Transport.connect()
            // XXX - assume we're using SMTP
            if (mailhost != null)
            props.put("mail.smtp.host", mailhost);

            // Get a Session object
            Session session = Session.getInstance(props, null);
            //debug= true;
            if (debug)
            session.setDebug(true);

            // construct the message
            Message msg = new MimeMessage(session);
            if (Emailfrom != null)
            msg.setFrom(new InternetAddress(Emailfrom, EmailTo,
arg_sEncoding));
            else
            msg.setFrom();

            if(arg_sEncoding.toLowerCase().equals("ISO8859_1"))
            {
             msg.setContent(Content, "text/html; charset=ISO8859_1");
            }else if(arg_sEncoding.toLowerCase().equals("MS950"))
            {
                msg.setContent(Content, "text/html; charset=MS950");
            }else if(arg_sEncoding.toLowerCase().equals("GB2312"))
            {
                msg.setContent(Content, "text/html; charset=GB2312");
            }

            msg.setRecipients(Message.RecipientType.TO,
                        InternetAddress.parse(EmailTo, false));
            /*if (cc != null)
            msg.setRecipients(Message.RecipientType.CC,
                        InternetAddress.parse(cc, false));
            if (bcc != null)
            msg.setRecipients(Message.RecipientType.BCC,
                        InternetAddress.parse(bcc, false));*/

            msg.setSubject(subject);

            // If the desired charset is known, you can use
            // setText(text, charset)
            //msg.setText(Content);

            msg.setHeader("X-Mailer", mailer);
            msg.setSentDate(new Date());

            // send the thing off
            Transport.send(msg);

            System.out.println("\nMail was sent successfully.");

        Rtr = true;
        }catch(Exception e) {
            e.printStackTrace();
        }
        return Rtr;
    }