> But, is there something I _should_ do in this situation, like > including > some text in the bounce saying that this address has never > existed, and > is being abused by spammers? If yes, _how_ should I do it?
I don't know what exactly you should do, i am not aware of the best practices about this matter, but I guess informing people that you not the one to blame is not a bad idea. You can use the following line in your configuration file: receiver_try_verify = true in order to attempt to verify addresses before accepting mail. In this case all mails for invalid users are rejected and no bounces are sent. Take a look at the vacation package; you can set an autoresponder with it (though I am not sure you can configure it to alter a bounce). Another program you might find useful is mailagent with which you can set filters to catch mails for any unknown user and take appropriate actions. I suggest not enabling the verify command. Hope I helped a bit. ~kmag