The MailHandlerTest fails due to the bad-host-name being resolved on my ISP.

1. Need to update the test to compute a host name that can't be resolved.
2. Update the code coverage in com.sun.mail.util.logging package after testing with JaCoCo. This was going to be committed but got lost in the repo moves.
3. Update MailHandler tests to include a host name entry in the session to prevent host name lookups. This will help speed up the test by avoid DNS lookups.