Java EE (Java Enterprise Edition) General Discussion

I hope someone can help me please. I keep getting the following error whenever I try and send a mail. I don't understand why as the same code functions perfectly in my dev environment(JBuilder 4), but under Tomcat 3.2.1 it throws this.

I have got both the mail.jar and activation.jar in my classpath.

Is this something to do with Tomcat??

javax.servlet.ServletException: Sending failed;
nested exception is:
javax.mail.MessagingException: IOException while sending message;
nested exception is:
javax.activation.UnsupportedDataTypeException: no object DCH for MIME type text/html
at org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:459)
at marketing._0002fmarketing_0002fkermitMail_0002ejspkermitMail_jsp_0._jspService(_0002fmarketing_0002fkermitMail_0002ejspkermitMail_jsp_0.java:200)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:119)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:177)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:318)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:391)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
at org.apache.tomcat.core.Handler.service(Handler.java:286)
at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
at org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:797)
at org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
at org.apache.tomcat.service.connector.Ajp12ConnectionHandler.processConnection(Ajp12ConnectionHandler.java:166)
at org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
at org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
at java.lang.Thread.run(Thread.java:484)

Any help much appreciated!!!