I finally got my domains and email servers caught up with 21st century technology: DomainKeys Identified Mail. No longer will my mailings end up in my customers' spamboxes! I made some debian packages that anyone who wants can install: "http://www.unternet.net/apt dubious main contrib non-free" goes in your /etc/apt/sources.list, and you get the package using: "apt-get -t dubious install exim4-daemon-custom".

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