Spam Filtering: February 2005 Archives

Julian gave a nice little snippet of perl to check the version of SA from the command line: perl -MMail::SpamAssassin -e 'print $Mail::SpamAssassin::VERSION;' Thanks Julian!

I am getting really tired of other people's anti-spam measures. I got the following from a mail server this morning (sanitised to protect the innocent): The address to which the message has not yet been delivered is: xx@xxxx.com Delay reason: SMTP error from remote mailer after RCPT TO:: host mail.xxxxx.com xx.xxx.xxx.xxx]: 451-Thank you for emailing xxx, due to our Anti-Spam policy , and since this 451-is the first e-mail to the company since 16th of February , your email has 451-been rejected. Please resend this e-mail after one hour and you will be 451-added to our safe senders list and you will no longer encounter this 451-message. We apologise for any inconveniene this may have casued. 451-xx.xxx.xxx.xxis not ye The mail in question contained important information for the client. How are we meant to do business with people who are implementing this kind of craziness on their SMTP servers? If you don't want spam I can respect that and I can advise you on how to avoid it, but this kind of carry on is detrimental to business communication.

A few weeks ago I started doing some work on geo specific filtering, where email is treated very differently depending on the sending IP. Since implementing this we have been very happy with the results. I also run a UML for my personal usage and for a couple of my pet projects. It's a nice place to try things out. Needless to say the domains hosted on it do get sent a lot of spam, however the main filters usually block most of it. Unfortunately spammers really do not care about respecting DNS "rules" and instead of mail being sent to the domains' MX an increasing amount of junk is hitting the A records.