When PowerDNS cannot retrieve the SOA record from a slave zone because the zone has a 'zone.com CNAME foo.bar.' record, it should print out a more informative message. Right now all it says is 'Unable to determine SOA serial for foo.com at potential supermaster 126.96.36.199' which could be more specific.
The exact same error message also appears in two other places in the code. It would be nice if those messages also had a correct reason.
Fixed in 1015