Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '209.48.172.0'
+117
ERRNo PTR record availible DNS server 'auth62.ns.uu.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.172.48.209.in-addr.arpa'.