Hi Roelof, > It's a header used by mailing lists to identify to which subscriber > the message was sent to. That makes it possible to recognise the > intended recipient when a message bounces. > Lots of mailing lists insert the name and address of the list in the > To: header, so that info can't be used. Hm, I don't think this is correct. As far as I know this header is inserted by the imap or pop server. Wait a second, I'll search on google:
http://www.claws-and-paws.com/spam-l/blocking.html X-UIDL There is a feature of the POP3 protocol, (which is used to download e-mail from your ISP) where you can issue a command called "UIDL" which will generate unique "identifiers" for each message where results in that header being written into the message. So, if your POP3 client doesn't add those in (like mine), you can safely filter on them. Here's a valid header, for reference: X-UIDL: b07a13a309dff618f53a09eeb9b966cc > There are more headers that are being used like this, it's software > dependant. Though X-UIDL is often encountered in spam, it's not > restricted to spam. (Unfortunately.) But it _IS_ possible to discover spam just analyzing the headers. There are various clues. And combining them, a pretty good estimate can be done. Spamassassin does that for example and it works great. Since the day I've installed it only _one_ SPAM got through to my inbox. :-) Andy. -- Dr. Andy Spiegl, Radio Marañón, Jaén, Perú E-Mail: [EMAIL PROTECTED], [EMAIL PROTECTED] URL: http://spiegl.de, http://radiomaranon.org.pe PGP/GPG: see headers o _ _ _ ------- __o __o /\_ _ \\o (_)\__/o (_) -o) ----- _`\<,_ _`\<,_ _>(_) (_)/<_ \_| \ _|/' \/ /\\ ---- (_)/ (_) (_)/ (_) (_) (_) (_) (_)' _\o_ _\_v ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ It's Friday, so I'll go to work early...even before lunch! (from BOfH) -- ________________________________________________________ Archives : http://tbudl.thebat.dutaint.com Moderators : mailto:[EMAIL PROTECTED] TBTech List: mailto:[EMAIL PROTECTED] Unsubscribe: mailto:[EMAIL PROTECTED] Latest Vers: 1.53d FAQ : http://faq.thebat.dutaint.com