diff --git a/lib/adauth/ad_object.rb b/lib/adauth/ad_object.rb
index 78681b5..c9e927f 100644
--- a/lib/adauth/ad_object.rb
+++ b/lib/adauth/ad_object.rb
@@ -33,6 +33,12 @@ def method_missing(method, *args)
           return super
         end
 
+        def respond_to?(method, include_private = false)
+          field = self.class::Fields[method]
+          return true if field
+          return super
+        end
+
         def self.reverse_field(search)
           hash = {}
           self::Fields.each do |k, v|