Javax.servlet.ServletException: Unknown SMTP host

Question

Hi
I am using tomcat and trying to send emails. I keep getting a javax.servlet.ServletException: Unknown SMTP host error.
I initially thought the problem was with the line: props.put("mail.smtp.host", "makethegrade.co.za"); But i checked the smtp info with the guys i'm hosing with and they said its right
I am currently setting the fields manually, so it can't be a problem with passing data around in the webpage
In my WEB-INF/lib i have jaf-1.0.2 and javamail-1.4.1 (i.e. mail.jar and activation.jar)
The code for my mailer bean is:
package mailer;
import java.io.*;
import java.util.*;
import javax.mail.*;
import javax.mail.event.*;
import javax.mail.internet.*;
public final class MailerBean extends Object implements Serializable {
     /* Bean Properties */
     private String to = null;
     private String from = null;
     private String subject = null;
     private String message = null;
     public static Properties props = null;
     public static Session session = null;
     static {
          /*     Setting Properties for STMP host */
          props = System.getProperties();
          props.put("mail.smtp.host", "makethegrade.co.za");
          session = Session.getDefaultInstance(props, null);
     /* Setter Methods */
     public void setTo(String to) {
          this.to = to;
     public void setFrom(String from) {
          this.from = from;
     public void setSubject(String subject) {
          this.subject = subject;
     public void setMessage(String message) {
          this.message = message;
     /* Sends Email */
     public void sendMail() throws Exception {
          if(!this.everythingIsSet())
               throw new Exception("Could not send email.");
          try {
               MimeMessage message = new MimeMessage(session);
               message.setRecipient(Message.RecipientType.TO,
                    new InternetAddress(this.to));
               message.setFrom(new InternetAddress(this.from));
               message.setSubject(this.subject);
               message.setText(this.message);
               Transport.send(message);
          } catch (MessagingException e) {
               throw new Exception("Caught in sendMail" + e.getMessage());
     /* Checks whether all properties have been set or not */
     private boolean everythingIsSet() {
          if((this.to == null) || (this.from == null) ||
             (this.subject == null) || (this.message == null))
               return false;
          if((this.to.indexOf("@") == -1) ||
               (this.to.indexOf(".") == -1))
               return false;
          if((this.from.indexOf("@") == -1) ||
               (this.from.indexOf(".") == -1))
               return false;
          return true;
}and the error i get is:
org.apache.jasper.JasperException: Exception in JSP: /processingPages/mailer.jsp:17
14:           mailer.setFrom("[email protected]");
15:           mailer.setSubject("mailer test");
16:           mailer.setMessage("TEst test test");
17:           mailer.sendMail();
18:           
19:      %>
20: </jsp:useBean>
Stacktrace:
     org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:451)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:355)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
root cause
javax.servlet.ServletException: Unknown SMTP host: mail.yourisp.com
     org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:841)
     org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:774)
     org.apache.jsp.processingPages.mailer_jsp._jspService(mailer_jsp.java:89)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
root cause
java.lang.Exception: Unknown SMTP host: mail.yourisp.com
     mailer.MailerBean.sendMail(MailerBean.java:54)
     org.apache.jsp.processingPages.mailer_jsp._jspService(mailer_jsp.java:67)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
Tomcat logs give:
Jul 15, 2009 10:50:35 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet jsp threw exception
java.lang.Exception: Unknown SMTP host: mail.yourisp.com
     at mailer.MailerBean.sendMail(MailerBean.java:54)
     at org.apache.jsp.processingPages.mailer_jsp._jspService(mailer_jsp.java:67)
     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
     at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)
     at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200)
     at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283)
     at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:773)
     at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703)
     at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:895)
     at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
     at java.lang.Thread.run(Thread.java:619)
If anyone needs any other details feel free to ask.
Any help or any pointers to a place to find a solution would be deeply appreciated
Thanks

Answer 1

All I can see is that you are running this in a web application. In most web application containers there's a place where you configure your mail providers and mail sessions. You seem to be ignoring that (you aren't using JNDI to get a session for example) but you are getting the default instance, so perhaps that uses that configuration anyway.