Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '2001:67c:b4::'
+297
ERRNo PTR record availible DNS server 'rirns.arin.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.4.b.0.0.c.7.6.0.1.0.0.2.ip6.arpa'.