To: abuse@host4u.net, postmaster@host4u.net
 Subject: Spam mail complaint
 
     Hi. Some jerk is using your servers to spam people with unsolicited
     commercial (SPAM) mail. If they are users on your system, please cease
     providing service to them immediately. Thank you.
     If your site was used to relay rather than originate SPAM, you should 
     configure your system to prevent this from happening. A URL which contains 
     instructions for doing this for most public and private email systems is 
     http://maps.vix.com/tsi/ - everything from smail to Exchange and Lotus Notes 
     is discussed.
 
 --
 PS: In case you're a spammer: you had fraudulent headers and probably
     intentionally misleading subject data. (Part of the fraudulent
     header.) Sending fraudulent email of this type to or from addresses
     physically located in Washington state is now illegal. (All forged
     header data falls under the law. Particularly From: and Subject:)
     And it is your legal responsibility to determine whether an address
     is in Washington state.

Figure 9   Mail to Relaying ISP

 To: abuse@euromar-travel.com , postmaster@euromar-travel.com 
 Subject: Spam mail complaint
 
     Hi. Some jerk is using your servers to relay unsolicited commercial 
    ("SPAM") email. You should configure your system to prevent 
    this from happening, since it's your disk space and CPU-time that they're 
    stealing. A URL which points to a page containing instructions for doing 
    this for most public and private email systems is http://maps.vix.com/tsi/ 
    - everything from smail to Exchange and Lotus Notes is discussed.