diff --git a/vendor/plugins/design/init.rb b/vendor/plugins/design/init.rb
index a51b0c0..d8a924f 100644
--- a/vendor/plugins/design/init.rb
+++ b/vendor/plugins/design/init.rb
@@ -5,6 +5,9 @@ class ActionController::Base
   # Declares that this controller uses design plugin to generate its layout.
   # See the plugin README for options that can be passed to this method.
   def self.design(config = {})
+
+    raise ArgumentError.new("design argument must be a Hash") unless config.kind_of? Hash
+
     if (config.has_key?(:holder) && config.has_key?(:fixed)) || (!config.has_key?(:holder) && !config.has_key?(:fixed))
       raise ArgumentError.new("You must supply either <tt>:holder</tt> or <tt>:fixed</tt> to design.")
     end
diff --git a/vendor/plugins/design/test/design_test.rb b/vendor/plugins/design/test/design_test.rb
index 7b9cf05..12850d5 100644
--- a/vendor/plugins/design/test/design_test.rb
+++ b/vendor/plugins/design/test/design_test.rb
@@ -1,6 +1,6 @@
 require File.join(File.dirname(__FILE__), 'test_helper')
 
-class FixedDesignHolderTest < Test::Unit::TestCase
+class DesignTest < Test::Unit::TestCase
 
   def test_design_should_include_design_module
     assert FixedDesignTestController.included_modules.include?(Design)
@@ -21,4 +21,10 @@ class FixedDesignHolderTest < Test::Unit::TestCase
       DesignEditorTestController.design :holder => 'something', :fixed => true end
   end
 
+  def test_should_not_accept_non_hash
+    assert_raise ArgumentError do
+      DesignEditorTestController.design :fixed
+    end
+  end
+
 end
diff --git a/vendor/plugins/design/test/test_helper.rb b/vendor/plugins/design/test/test_helper.rb
index 026ecf5..bf98f51 100644
--- a/vendor/plugins/design/test/test_helper.rb
+++ b/vendor/plugins/design/test/test_helper.rb
@@ -3,6 +3,9 @@ require File.expand_path(File.dirname(__FILE__) + "/../../../../config/environme
  
 require 'test/unit'
 
+# from Rails
+require 'test_help'
+
 # load the database schema for the tests
 ActiveRecord::Base.logger = Logger.new(File.dirname(__FILE__) + "/debug.log")
 load(File.dirname(__FILE__) + '/schema.rb')
--
libgit2 0.21.2