[lug] email mystery

[D. Stimits]

I'm trying to figure out how some of the spam email gets to me. The full
headers don't show me anywhere in the path, although it does show the
email servers from my ISP. The ISP uses a mix of Linux and NT boxes. Is
there some sort of mass email feature to allow sending to everyone at
some domain? Here is a sample full header I got:

Return-Path: 
                 <crdserv at yahoo.com>
        Received: 
                 from totalrecall.idcomm.com (totalrecall.idcomm.com
[207.40.196.5]) by mailhost.idcomm.com
                 (8.10.0/8.10.0) with ESMTP id f1KDK4p16394; Tue, 20 Feb
2001 06:20:04 -0700
        Received: 
                 from dns2.kokushikan.ac.jp (dns2.kokushikan.ac.jp
[202.253.226.22]) by totalrecall.idcomm.com
                 (8.9.3/8.9.3) with ESMTP id GAA19192; Tue, 20 Feb 2001
06:18:31 -0700
           From: 
                 crdserv at yahoo.com
        Received: 
                 from yahoo.com (localhost [127.0.0.1]) by
dns2.kokushikan.ac.jp (8.9.3+3.2W/3.7Wpl2/02/06/01) with
                 SMTP id WAA03068; Tue, 20 Feb 2001 22:16:19 +0900 (JST)
            Date: 
                 Tue, 20 Feb 2001 22:16:19 +0900 (JST)
      Message-ID: 
                 <200102201316.WAA03068 at dns2.kokushikan.ac.jp>
        Reply-To: 
                 crdserv at yahoo.com
              To: 
                 crdserv at yahoo.com
          Subject: 
                 Clear Up Bad Credit Today! Get approved for loans and
more...
  X-Mozilla-Status: 
                 8001
 X-Mozilla-Status2: 
                 00000000
          X-UIDL: 
                 _RAE.H8mk6.mailhost