Ubuntu postfix SMTP服务器未从java代码连接

我已经在ubuntu服务器上用SASL配置了postfix smtp。我能够从服务器上的命令行发送邮件（命令是echo“mail Body”| mail-s“some subject”to_email）_id@mailprovider.com)但无法从java代码发送邮件。这里有一些细节- Java代码-

package test;

import java.util.Date;
import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class TestEmail {
    public static void main(String[] args) {
        final String username = "username";
        final String password = "password";
        final String domain = "@domainchanged.com";
        String to = "to_email@gmail.com";
        String from = username + domain;
        String host = "192.168.10.39";
        Properties properties = new Properties();
        properties.put("mail.debug", "true");
        properties.put("mail.smtp.starttls.enable", "true");
        properties.put("mail.smtp.host", host);
        properties.put("mail.smtp.port", "587");
        properties.put("mail.smtp.auth", "true");
        properties.put("mail.smtp.socketFactory.port", 587);
        properties.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        properties.put("mail.smtp.socketFactory.fallback", "false");
        Session session = Session.getDefaultInstance(properties, new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(username, password);
            }
        });
        try {
            Message msg = new MimeMessage(session);
            msg.setFrom(new InternetAddress(from));
            InternetAddress[] address = {
                new InternetAddress(to)
            };
            msg.setRecipients(Message.RecipientType.TO, address);
            msg.setSubject("Via code it works.");
            msg.setSentDate(new Date());
            msg.setText("Some email Body.");
            Transport.send(msg);
        }
        catch (MessagingException mex) {
            mex.printStackTrace();
        }
    }
}

获取此异常-

DEBUG: JavaMail version 1.4.7
DEBUG: successfully loaded resource: /META-INF/javamail.default.providers
DEBUG: Tables of loaded providers
DEBUG: Providers Listed By Class Name: {com.sun.mail.smtp.SMTPSSLTransport=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Oracle], com.sun.mail.smtp.SMTPTransport=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Oracle], com.sun.mail.imap.IMAPSSLStore=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Oracle], com.sun.mail.pop3.POP3SSLStore=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Oracle], com.sun.mail.imap.IMAPStore=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Oracle], com.sun.mail.pop3.POP3Store=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Oracle]}
DEBUG: Providers Listed By Protocol: {imaps=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Oracle], imap=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Oracle], smtps=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Oracle], pop3=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Oracle], pop3s=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Oracle], smtp=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Oracle]}
DEBUG: successfully loaded resource: /META-INF/javamail.default.address.map
DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Oracle]
DEBUG SMTP: useEhlo true, useAuth true
DEBUG SMTP: trying to connect to host "192.168.10.39", port 587, isSSL false
javax.mail.MessagingException: Could not connect to SMTP host: 192.168.10.39, port: 587;
  nested exception is:
    java.net.SocketException: Permission denied: connect
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1961)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:654)
    at javax.mail.Service.connect(Service.java:295)
    at test.TestEmail.main(TestEmail.java:51)
Caused by: java.net.SocketException: Permission denied: connect
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
    at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
    at java.net.Socket.connect(Socket.java:529)
    at java.net.Socket.connect(Socket.java:478)
    at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:321)
    at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:237)
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1927)
    ... 3 more

这是来自服务器的ehlo响应-

~$ telnet 192.168.10.39 587
Trying 192.168.10.39...
Connected to 192.168.10.39.
Escape character is '^]'.
220 domainchanged.com ESMTP Postfix (Ubuntu)
ehlo domainchanged.com
250-domainchanged.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN

我能够使用telnet（从另一台机器）连接到此服务器，并且能够成功地进行身份验证（使用telnet的AUTH登录）。需要帮助才能理解我遗漏了什么。希望我已经提供了足够的细节，请询问是否还有其他需要