I recently switched our email filtering solution from Postini to EdgeWave. We are only paying for inbound filtering so I created a Smart Host on our server for outbound message relaying. Well, I got an email from someone at EdgeWave saying that it appears that we may be compromised as spammers are relaying off of our server sending spam. They said they are blocking them on their end, but for me to address this issue on our server. What does this mean? What do I have to do to stop this on our server?