Problema ao enviar Email [AJUDA](simple mail - jakarta)

package br.gov.ce.seplag.cronmail.actions;

import java.util.Date;

import org.apache.commons.mail.EmailException;
import org.apache.commons.mail.SimpleEmail;
import org.quartz.SchedulerException;

import br.gov.ce.seplag.cronmail.definicoes.EmailDefinicoes;

import com.opensymphony.xwork2.ActionSupport;

import freemarker.core.ParseException;

/**
 * ActionSADMail é a ação responsável pelo envio de email para o módulo agendador do
 * sistema SAD
 * @author bernardo
 *
 */
public class ActionSADMail extends ActionSupport{

	private static final long serialVersionUID = 4881722358860240980L;
	String hoje = new java.text.SimpleDateFormat("dd/MM/yyyy HH:mm:ss").format(new Date());	
	private String subject = "Aviso - CronMail - " + hoje; 

	public String execute(String emailTo, String nomeTo
			, String msg) throws SchedulerException, ParseException
			, InterruptedException, java.text.ParseException {
		
		SimpleEmail email = new SimpleEmail();
		email.setHostName(EmailDefinicoes.getServidorEmail());
		
		try {
			email.addTo(emailTo, nomeTo);
			email.setFrom(EmailDefinicoes.getMsgFrom(), EmailDefinicoes.getNomeFrom());
			//email.setSubject(EmailDefinicoes.getSubject());
			email.setSubject(subject);
			email.setMsg(msg);
			email.send();
		} catch (EmailException e) {
			e.printStackTrace();
		}
        return SUCCESS;
    }
}

org.apache.commons.mail.EmailException: Sending the email to the following server failed : 172.25.4.24:25        at org.apache.commons.mail.Email.sendMimeMessage(Email.java:1138)        at org.apache.commons.mail.Email.send(Email.java:1163)        at br.gov.ce.seplag.cronmail.actions.ActionSADMail.execute(ActionSADMail.java:40)        at br.gov.ce.seplag.cronmail.jobs.JobSADVerificaAcoes.execute(JobSADVerificaAcoes.java:137)        at org.quartz.core.JobRunShell.run(JobRunShell.java:202)        at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:529)Caused by: javax.mail.MessagingException: 501 Command "HELO" requires an argument