I am not a spammer...I'm a free man!
I mentioned my email troubles in this item from a couple days ago. Since then I've been poring over my sendmail config, my firewall config, my DNS config, everything I could think of to get to the root of the problem. I tried sending outgoing email, and one of these resulted in an interesting bounce saying Service unavailable: [my IP address] blocked using +dialups.relays.osirusoft.com. Blocked?
So I went over to http://relays.osirusoft.com and discovered my address was indeed listed among the malefactors in their database:
(127.0.0.3) NNN.NN.NN.NNN is DNSbl listed. by dialups.relays.osirusoft.com This zone is for Dynamic IP Space that have been an injection point for spam. Please use your ISP's server instead.
Good grief, use Verizon's email server? The whole point of this is to be able to avoid spam, not to court it. Anyway, I ran a scan of my address from their site and came up without signs of trouble, and sent the admins a note requesting removal from the database.
So my little server is experiencing collateral damage in the Spam Wars. And I'm not the only one.
Postscript: while I was composing the rest of this note, I received a spam at my Yahoo account. Bastards!