Received from: mail.sendingemail.com (mail.sendingemail.com [xx.7.239.25])
by mail.receivingemail.com (Postfix) with ESMTP id T12FG932 for
you@receivingemail.com; Tue, 04 April 2005 23:01:22 -0800 (PST)
This first header tells us that this message was received by a server dubbed
mail.sendingemail.com.The parentheses show the verification of identity, stating
that a DNS reverse lookup revealed that the IP matches this identification and
that xx.7.239.25 is the IP address the message came in from.The mail server that
received the e-mail is mail.receivingemail.com, which is running Postfix ESMTP
with an arbitrary id of T12FG932.The ID is arbitrary and constr ...