summarizing Kay Roepke's private reply, this is a known bug: http://bugs.mysql.com/bug.php?id=38415
moreover, he has created a launchpad blueprint in February https://blueprints.launchpad.net/mysql-proxy/+spec/remove-unix-socket -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org