test1 creating, saving, loading simple messages
test2 camelinternetaddress tests, internationalised addresses, etc.
test3 multipart messages
test4 more encompassing mime parser tests that test real-world messages.
Note: In order to test this, though, you'll need to fetch
http://primates.ximian.com/~fejj/camel-mime-tests.tar.gz and
untar it into camel/tests/data/