My email server has been put on a blacklist. However, when I scan my email server for viruses/bots/etc., it scans clean.
My email server is Exchange 5.5 which I am going to upgrade asap.
Since my server scans clean right now, and since I will be upgrading it to a supported version of Exchange, after the upgrade I will still be unsure if I have actually fixed the source of the spam problem.
It would be nice to have something on my local network that can identify a source of spam.
It would also be nice to be able to look at real-time statistics of any spam that supposedly comes from my network. For example, something that says "On January 1, 2008, we received 100 spam messages originating from ip adress xxx on your domain, On January 2, 2008, we received 50 spam messages originating from ip adress xxx on your domain,", etc. This would be a good monitor for me - after upgrading my email server (that I can't seem to find a problem on), I could then see if the number of spam messages originating from my domain has decreased, etc.