请指点一下Servlet中发送Email的问题？？？

本人在局域网中配置了一个Exchange邮件服务器，想在一台Tomcat服务器上运行Servlet来发送邮件，Servlet编译没有出错。

其中一段代码如下：
//------------------------------------------------------------------------
out.println("one");
message = new MimeMessage(session);
out.println("two");
message.setFrom(new InternetAddress(from));
out.println("three");
message.addRecipient(Message.RecipientType.TO,new InternetAddress(to));
out.println("four");
message.setSubject(subject);
out.println("five");
message.setText(body);
out.println("six");
Transport.send(message);
out.println("seven");
message.setSentDate(new Date());
out.println("eight");
throwSuccessMessage(out);
//------------------------------------------------------------------------

程序运行时报错如下：
//------------------------------------------------------------------------

one two three four five six javax.mail.NoSuchProviderException: smtp

//------------------------------------------------------------------------

请各位大侠指点。