After updating from 2.1.2 to 2.2.2, all my DNS server were 'Open DNS servers' again. When I was using 2.1.2 I added the 'fix' for this in both named.conf files!
Looking at the named.conf in /root/ispconfig/isp/conf/named.conf.master
and in /etc
is missing again!
After adding it, and restarting named, the DNS server is closed and ok :-)