Error connecting to SMTP using javamail

this is the code i am using to send email

import java.util.Date;
import java.util.Properties;
import javax.activation.CommandMap;
import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.activation.MailcapCommandMap;
import javax.mail.Authenticator;
import javax.mail.BodyPart;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;

public class Mail extends Authenticator {
    private String _user;
    private String _pass;

    private String[] _to;
    private String _from;

    private String _port;
    private String _sport;

    private String _host;


    private String _subject;
    private String _body;

    private boolean _auth;

    private boolean _debuggable;

    private Multipart _multipart;

    public String[] get_to() {
        return _to;
    }

    public void set_to(String[] _to) {
        this._to = _to;
    }

    public String get_from() {
        return _from;
    }

    public void set_from(String _from) {
        this._from = _from;
    }



    public String get_subject() {
        return _subject;
    }

    public void set_subject(String _subject) {
        this._subject = _subject;
    }


    public Mail() {                 
        _host = "mail.messagingengine.com";    
    _port = "587";  
        _sport = "587"; 
        _user = ""; // username
        _pass = ""; // password
        _from = ""; // email sent from
        _subject = ""; // email subject
        _body = ""; // email body

        _debuggable = false; // debug mode on or off - default off
        _auth = true; // smtp authentication - default on

        _multipart = new MimeMultipart();

        // There is something wrong with MailCap, javamail can not find a
        // handler for the multipart/mixed part, so this bit needs to be added.
        MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap();
        mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
        mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
        mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
        mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
        mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");
        CommandMap.setDefaultCommandMap(mc);
    }

    public Mail(String user, String pass) {
        this();

        _user = user;
        _pass = pass;
    }

    public boolean send() throws Exception {
        Properties props = _setProperties();

        if (!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") && !_subject.equals("")
                && !_body.equals("")) {
            Session session = Session.getInstance(props, this);

            MimeMessage msg = new MimeMessage(session);

            msg.setFrom(new InternetAddress(_from));

            InternetAddress[] addressTo = new InternetAddress[_to.length];
            for (int i = 0; i < _to.length; i++) {
                addressTo[i] = new InternetAddress(_to[i]);
            }
            msg.setRecipients(MimeMessage.RecipientType.TO, addressTo);

            msg.setSubject(_subject);
            msg.setSentDate(new Date());

            // setup message body
            BodyPart messageBodyPart = new MimeBodyPart();
            messageBodyPart.setText(_body);
            _multipart.addBodyPart(messageBodyPart);

            // Put parts in message
            msg.setContent(_multipart);


            Transport.send(msg);

            return true;
        } else {
            return false;
        }
    }

    public void addAttachment(String filename) throws Exception {
        BodyPart messageBodyPart = new MimeBodyPart();
        DataSource source = new FileDataSource(filename);
        messageBodyPart.setDataHandler(new DataHandler(source));
        messageBodyPart.setFileName(filename);

        _multipart.addBodyPart(messageBodyPart);
    }

    @Override
    public PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(_user, _pass);
    }

    private Properties _setProperties() {
        Properties props = new Properties();

        props.put("mail.messagingengine.com", _host);
        // mail.messagingengine.com

        if (_debuggable) {
            props.put("mail.debug", "true");
        }

        if (_auth) {
            props.put("mail.smtp.auth", "true");
        }

        props.put("mail.smtp.port", _port);


        props.put("mail.smtp.socketFactory.port", _sport);
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.socketFactory.fallback", "false");

        return props;
    }

    // the getters and setters
    public String getBody() {
        return _body;
    }

    public void setBody(String _body) {
        this._body = _body;
    }

    // more of the getters and setters …..
}

      

        
        
        
      

    

this error argument after the transport.send (msg) command;

javax.mail.MessagingException: Could not connect to SMTP host: mail.messagingengine.com, port: 587;
  nested exception is:
    javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x1f81518: Failure in SSL library, usually a protocol error
error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol (external/openssl/ssl/s23_clnt.c:683 0x4025bc93:0x00000000)