I haven't seen this before, but when I googled for "no object DCH for MIME"
I came up with this page that might help:
http://www.jguru.com/faq/view.jsp?EID=237257
People are saying that this results from a mismatch between different
versions of activation.jar vs. mail.jar. It's possible that Tomcat is
loading one of them from its own directories and one from the XTF directory.
So you might try replacing the ones in the XTF directory with those from
Tomcat, or maybe removing them in the hopes that Tomcat will load the proper
jars.
--Martin