maybe turn off exim
/etc/init.d/exim4 stop
+ mv /etc/rc2.d/S20exim4 /etc/rc2.d/K20exim4 # so it stays down
install deborphan, clean up
dpkg --get-selections | awk '$2!="install" {print $1}'
echo "really purge these [y/N]?"; read ans; [ "$ans" = "y" ] && dpkg --purge `dpkg --get-selections | awk '$2!="install" {print $1}'`
+
+possibly reboot
+
+re-enable exim
+ mv /etc/rc2.d/K20exim4 /etc/rc2.d/S20exim4
+ env -i /etc/init.d/exim4 start