I'm building a package with debhelper, and my package's configuration files go into /etc/muddleftpd. When purging the package that I build, I get this from dpkg: dpkg - warning: while removing muddleftpd, directory `/etc/muddleftpd' not empty so not removed. I get the feeling i'm overlooking something simple that's caused this error. What is the correct way to make sure this directory is gone?