We are organizing periodic surveys and we would like to make sure that we dont send invitations to people who dont like to recieve them (even if we go through double opt-in process some users after sometime get bored of surveys and instead of unsubscribing start marking emails as spam. So to indentify such users and drom them from the mailing list we would like to subscribe to 'feedback loop' information from google.

Google provide a possibitlity to recieve such feedback but an additional hearder( List-Unsubscribe header) should be sent in a email.

Is it possible to add such hearder if our mail sending option is SMTP.

More information about this:
www.returnpath.net/blog/intheknow/2009/0...-mailing-lists/#more

Feedback loops:
en.wikipedia.org/wiki/Feedback_loop_%28email%29

That's a good idea. Please submit it to ideas.limesurvey.org

Yep, and List-unsuscribe aren't google specific, it was on a mail draft.

Used by a lot of mailing list system.

Good option !

Added to Idea inbox.

Please vote if you like this feature.

ideas.limesurvey.org/ideatorrent/idea/380/

Any ideas how this can be implemented?