Nobody at “cmiyc.com” or “cmiyc.org” will send you email. In fact, I don’t even have an outgoing mail server setup. So if you receive emails from me, a spammer is forging my domain name in the email headers.
There is little that can prevent this, since it is something that happens in between you and I. All I can say, it is perfectly safe to drop any emails that appear to come from “cmiyc.com”.
More information about this type of attack, referred to as a “Joe Job”, can be found in this Wikipedia Article.