http://sourceforge.net/projects/eximdsn/

DSN Support for Exim. This patch allows Exim 4.xx to support the sending of email Delivery Status Notifications.

http://sourceforge.net/project/showfiles.php?group_id=121058
http://prdownloads.sourceforge.net/eximdsn/exim_462_dsn_1_2.patch?download
http://surfnet.dl.sourceforge.net/sourceforge/eximdsn/exim_462_dsn_1_2.patch