Comment 4 for bug 761967

The tomcat6 fix was to call start-stop-daemon with the -b (--background) flag. This may not be a proper fix here, as this would require both opendkim and dk-filter packages to make the change (among other packages, I assume) and could result in silent failures when starting these daemons.

The most likely culprit I can find is 3706d6214a86593e72bc9514f08f3c4e0fd0a92c in git://git.debian.org/git/dpkg/dpkg.git, which changed the start-stop-daemon behavior around opening, closing, and detaching from the tty.