diff --git a/config/initializers/10-patches.rb b/config/initializers/10-patches.rb
index ea11311ba..d739e6ce0 100644
--- a/config/initializers/10-patches.rb
+++ b/config/initializers/10-patches.rb
@@ -88,3 +88,16 @@ module ActionController
     end
   end
 end
+
+module ActionController
+  class Base
+    # Displays an explicit message instead of a NoMethodError exception
+    # when trying to start Redmine with an old session_store.rb
+    # TODO: remove it in a later version
+    def self.session=(*args)
+      $stderr.puts "Please remove config/session_store.rb and run `rake generate_secret_token`.\n" +
+        "Setting the session secret with ActionController.session= is no longer supported in Rails 3."
+      exit 1
+    end
+  end
+end