comast email issues, who else has them?

Sean Donelan sean at
Fri Sep 1 15:45:53 UTC 2006

On Thu, 31 Aug 2006, Tony Li wrote:
> I've taken the rather extreme approach of bouncing everything through
> Gmail first.  Let's see them block Google.  ;-)

Patient: Doctor, Doctor, It hurts when I do this.
Doctor: Don't do that.

There are lots of Mail Service Providers.  AOL, Comcast, Gmail, Yahoo, 
Outblaze, whoever, each have their own quirks and problems.  All have 
blocked various sources including each other at one time or another.
Some people complain about some of the decisions made by each of them; 
while other people applaud the same decisions.

Perhaps people are using the wrong tools to solve the problems?

Trying to forward from one account to another through spam filters is 
probably not a good idea, especially since the primary filtering mechanism 
used by most anti-spam technologies is based on the connecting host.  You
generally can't "trust" the originating IP address information of other
hops, if they are even present.  For example, Gmail doesn't include the
originating IP address in its email which makes it even more difficult for 
spam filters to judge its reputation. If a system forwards unfiltered 
e-mail in today's Internet, it is forwarding spam, viruses, and other 
malicious stuff, and will likely continue to trip defensive controls on

Different tools such as fetchmail, multi-mailbox POP/IMAP clients, etc
may be more appropriate in today's Internet. Bulk forwarding of 
unfiltered e-mail is probably not a good idea. If systems are going to
forward e-mail, it may be a good idea to use spam filters BEFORE 
forwarding the messages and use a distinct forwarding IP connections for
those messages so the receiver can treat those messages as pre-filtered
and direct complaints about those messages to the forwarder for handling.

There are several other mailing lists covering the topics of e-mail,
e-mail forwarding, spam technologies, etc.

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