The permissions of /etc/mail/mimedefang-filter are set to 400 on install. Should be 600. Read-only config files are a bit silly :-) Reproducible: Always
May even need to be 644 as mimedefang does not run as root usually.
I sort of like stuff in /etc being read-only, for the added confirmation before overwriting a file, but I agree that it's non-standard and it's up to everyone to decide if they want this "protection". Fixed in CVS, thanks.