=== modified file 'debian/lxc.postinst'
--- debian/lxc.postinst	2013-02-08 21:25:36 +0000
+++ debian/lxc.postinst	2013-03-27 19:43:50 +0000
@@ -72,6 +72,27 @@
 # We need this after the debhelper generated code so that dpkg-maintscript
 # can do its renamming first.
 if [ "$1" = "configure" ]; then
+
+    # The dnsmasq hook has been introduced through SRU into Ubuntu 12.04
+    # and Ubuntu 12.10.
+    #
+    # This means that even though we version-guard the maintscripts entry
+    # it'll fire multiple times for users doing 12.04 => 12.10 => 13.04
+    # or even just 12.10 => 13.04.
+    #
+    # As there's unfortunately no way to specify per-series base versions
+    # for maintscripts hooks, we let it fire multiple times and then fix up
+    # the mess it creates.
+    #
+    # This migration code can be removed after Ubuntu 14.04 LTS is released.
+    if [ -L /etc/dnsmasq.d-available/lxc ] &&
+       [ "$(readlink /etc/dnsmasq.d-available/lxc)" = "/etc/dnsmasq.d-available/lxc" ] &&
+       [ -e /etc/dnsmasq.d-available/lxc.dpkg-new ]; then
+        echo "The dnsmasq configuration has been migrated twice, fixing it."
+        mv /etc/dnsmasq.d-available/lxc /etc/dnsmasq.d/lxc
+        mv /etc/dnsmasq.d-available/lxc.dpkg-new /etc/dnsmasq.d-available/lxc
+    fi
+
     # Configure dnsmasq
     if [ -f /etc/dnsmasq.d-available/lxc ]; then
         echo "Setting up lxc dnsmasq configuration."