Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '207.90.252.0'
+057
ERRNo PTR record availible DNS server 'y.arin.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.252.90.207.in-addr.arpa'.