I didn't send a virus -- why does your software claim I did?
Many viruses forge the sender’s address. By default, MIMEDefang does not send notifications to virus senders for this very reason.
We strongly recommend to MIMEDefang administrators that they do not change this behaviour.
However, some MIMEDefang administrators insist on sending notifications to the apparent sender of a virus.
This is bad behaviour, but we cannot control it. Complain to the ISP in question, or blacklist it until it fixes the configuration.