Authors Note:
I use the exim MTA (Mail Transfer Agent) on running locally on my machine, it seemlessly provides delivery for multiple mail accounts running on any network anywhere. Exim can be configured, as it is on my machine, to only accept e-mail messages sent from the local interface thus making relaying of spam impossible.

AOL doesn't like the fact that my relay originates from a dynamic IP (my cable modem ISP uses DHCP) and automatically blacklists me as a spammer.

Normally I wouldn't mind, my solution is to simply not communicate with the poor fools who happen to use AOL, but in this instance the poor user happened to be one of my students.

I wanted to let AOL know about the error in their ways... I should have seen it coming:

From: Mail Delivery System 
Date: Sun Jun 22, 2003  12:52:05 PM US/Eastern
To: @cs.umass.edu
Subject: Mail delivery failed: returning message to sender

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  postmaster@aol.com
    SMTP error from remote mailer after initial connection:
    host mailin-04.mx.aol.com [64.12.137.152]: 554- The IP address you are using to connect to AOL is a dynamic (residential)
    554- IP address.  AOL will not accept future e-mail transactions from this IP
    554- address until your ISP removes this IP address from its list of dynamic
    554- (residential) IP addresses.  For additional information, please visit
    554  http://postmaster.info.aol.com.

------ This is a copy of the message, including all the headers. ------

Return-path: <@cs.umass.edu>
Received: from localhost ([127.0.0.1] helo=cs.umass.edu)
	by vogon.cs.umass.edu with esmtp (Exim 4.12)
	id HGW6US-0004RA-00
	for postmaster@aol.com; Sun, 22 Jun 2003 12:52:04 -0400
Date: Sun, 22 Jun 2003 12:52:03 -0400
Mime-Version: 1.0 (Apple Message framework v552)
Content-Type: text/plain; charset=US-ASCII; format=flowed
Subject: Fwd: Mail delivery failed: returning message to sender
From: Brendan Burns <@cs.umass.edu>
To: postmaster@aol.com
Content-Transfer-Encoding: 7bit
Message-Id: 
X-Mailer: Apple Mail (2.552)

First let me say that I know that this message will in no way affect 
AOL's policies vis-a-vis mail blocking, but I need to get this off of 
my chest anyway...

The SMTP server through which I send mail is configured only to accept 
connections from my local machine.  It is therefore impossible for it 
to send messages which do not originate from my mail program.   I am 
neither an open-relay nor a spammer, yet AOL deems it necessary to 
black-list messages originating from my computer.  This is not an 
effective solution to the Spam problem.  Disabling people's ability to 
communicate to prevent spam is like cutting of someone's head to get 
rid of brain cancer.  That said, my normal response would be to say, 
screw them, that's there fault for using AOL.  In this case however the 
e-mail is from a student taking one of my courses.  Your incompetent 
spam policy has hindered his
education experience.  In class on monday I will inform him of the 
reasons why he has failed
to receive a response from me.  With any luck this will be enough to 
convince him that he
ought to switch ISPs to one with a more informed anti-spam policy.  
Although one customer leaving is of marginal importance to you I can 
assure you that continued mis-use of technology will cause people to 
leave in droves.

Besides which its just annoying to see someone doing something 
stupid... *sigh*

Yours,
Brendan Burns
Graduate Student
Department of Computer Science
University of Massaschusetts, Amherst

Begin forwarded message:

From: Mail Delivery System 
Date: Sat Jun 21, 2003  11:34:54 PM US/Eastern
To: @cs.umass.edu
Subject: Mail delivery failed: returning message to sender

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) 
failed:

  @aol.com
    SMTP error from remote mailer after initial connection:
    host mailin-02.mx.aol.com [64.12.136.89]: 554- The IP address you 
are using to connect to AOL is a dynamic (residential)
    554- IP address.  AOL will not accept future e-mail transactions 
from this IP
    554- address until your ISP removes this IP address from its list 
of dynamic
    554- (residential) IP addresses.  For additional information, 
please visit
    554  http://postmaster.info.aol.com.

------ This is a copy of the message, including all the headers. ------
...