dnssec-signzone mishandles
$TTL 300
example.com.    IN SOA  marka.isc.org. a.root.servers.nil. (
                   2026    ; serial
                   600     ; refresh
                   600     ; retry
                   1200    ; expire
                   600     ; minimum
                 )
example.com.            IN DNAME   ns2.smokeyjoe.com.
example.com.            IN NS      ns2.smokeyjoe.com.
foo.example.com.        IN NS      exavider.example.com.
exavider.example.com.   IN A       192.168.0.2

named is also likely to mishandle this zone when signing,