diff --git a/lib/ransack/adapters/active_record/compat.rb b/lib/ransack/adapters/active_record/compat.rb
index dbb7d7f..e447404 100644
--- a/lib/ransack/adapters/active_record/compat.rb
+++ b/lib/ransack/adapters/active_record/compat.rb
@@ -1,11 +1,47 @@
 module Arel
 
+  module Nodes
+    %w{
+      IDoesNotMatch
+      IMatches
+    }.each do |name|
+      const_set name, Class.new(Binary)
+    end
+  end
+
+  module Predications
+    def i_matches other
+      Nodes::IMatches.new self, other
+    end
+
+    def i_does_not_match other
+      Nodes::IDoesNotMatch.new self, other
+    end
+  end
+
   module Visitors
 
+    class ToSql < Arel::Visitors::Visitor
+      def visit_Arel_Nodes_IDoesNotMatch o
+        "UPPER(#{visit o.left}) NOT LIKE UPPER(#{visit o.right})"
+      end
+
+      def visit_Arel_Nodes_IMatches o
+        "UPPER(#{visit o.left}) LIKE UPPER(#{visit o.right})"
+      end
+    end
+
+    class Dot < Arel::Visitors::Visitor
+      alias :visit_Arel_Nodes_IMatches            :binary
+      alias :visit_Arel_Nodes_IDoesNotMatch       :binary
+    end
+
     class DepthFirst < Visitor
 
       unless method_defined?(:visit_Arel_Nodes_InfixOperation)
         alias :visit_Arel_Nodes_InfixOperation :binary
+        alias :visit_Arel_Nodes_IMatches            :binary
+        alias :visit_Arel_Nodes_IDoesNotMatch       :binary
       end
 
     end
diff --git a/lib/ransack/constants.rb b/lib/ransack/constants.rb
index 4f61755..0ba488f 100644
--- a/lib/ransack/constants.rb
+++ b/lib/ransack/constants.rb
@@ -12,11 +12,21 @@ module Ransack
         :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
         }
       ],
+      ['icont', {
+        :arel_predicate => 'i_matches',
+        :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
+      }
+      ],
       ['not_cont', {
         :arel_predicate => 'does_not_match',
         :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
         }
       ],
+      ['inot_cont', {
+        :arel_predicate => 'i_does_not_match',
+        :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
+      }
+      ],
       ['start', {
         :arel_predicate => 'matches',
         :formatter => proc { |v| "#{escape_wildcards(v)}%" }