did you change this to 99.99.99.99 to hide your real IP address? If not that was the problem... your correct IP was not in the DNS. Yi.org was telling mail servers your mail servers IP address was something else. That server did not allow the mail session. Had it pointed to the correct server (your e-smith) it would have worked.
It must have updated since, I can complete a mail session with your e-smith server from a remote location just fine. DNS is working now.