From: Jacob Fugal <lukfugl@...>
Date: 2005-09-24T05:14:09+09:00
Subject: Re: On accidental unsubscribe messages

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As long as you have access to something the likes of sendmail (plenty of
perl modules I know of and probably some ruby ones I don't know of) you can=
d
send a mail with any address you want. I get spam that claims to be from my
brother's email address (despite the first line being "Hi, my name is
LaFonda!") all the time.

HOWEVER, some (unfortunately not as many as there should be) servers will
perform a reverse DNS lookup on the domain you *claim* to be sending from,
and reject the email if it doesn't match the actual senders IP.

So... the questions are:

1) Does ruby-lang.org <http://ruby-lang.org> (or any intermediate SMTP
relay) perform RDNS checking?
2) Do you have access to some sendmail-ish program/library?

If the answers are No and Yes, respectively, than you can spoof the old
address and unsubscribe yourself. Otherwise... good luck getting a hold of
the human admin (or hacking into the old address' server).

Jacob Fugal

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