Altered the Geocoder#ip_address? method to recognize IP addresses pre…

…fixed with ::ffff: as is common with webservers binding to ipv6 sockets

lib/geocoder.rb

@@ -115,7 +115,7 @@ def spawn_lookup(name)
   # dot-delimited numbers.
   #
   def ip_address?(value)
-    !!value.to_s.match(/^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/)
+    !!value.to_s.match(/^(::ffff:)?(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/)
   end
 
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