org.jboss.soa.esb.samples.quickstart.helloworld_mail.test.SendMailMessage

requires javax.mail for these imports:

import javax.mail.Message;
import javax.mail.Message.RecipientType;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.URLName;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

A Java mail jar is not included in the client app. as installed.