I'm receiving it as well. Most probably, someone from this domain has subscribed to the mail list and now sender gets automated mail from postmaster complaining about return address.

Just ignore that

On Tue, Jul 2, 2013 at 8:11 PM, Robert Fletcher <robert@merciadragon.net> wrote:
Every time I have posted to this list today I have also received an email from Randomail with this text that I have listed below. I have a bad feeling about this as it seems that somehow mail going into the list is being intercepted along the line. It's only to this list that it's happening does any body know anything about it? Sorry to posting directly to the latest but I can't seem to find an admin address.

It's a message from Randomail's postmaster.
Adress motion-user@lists.sourceforge.net doesn't seems to exist.

You can do a tour on randomail at http://randomail.net , it's free!

Randomail, it's a redirection email service. Create your account and generate redirections. It's free and unlimited!

This SF.net email is sponsored by Windows:

Build for Windows Store.

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