diff --git a/lib/geocoder.rb b/lib/geocoder.rb
index a4b52ac55bab3f091cec83fc9d649a322d848fed..3b8636cc6d2a24f4abc9483b47f162db424ea826 100644
--- a/lib/geocoder.rb
+++ b/lib/geocoder.rb
@@ -115,7 +115,7 @@ module Geocoder
   # 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
 
   ##