diff --git a/test/rack_test.rb b/test/rack_test.rb
new file mode 100644
index 00000000..84734ea0
--- /dev/null
+++ b/test/rack_test.rb
@@ -0,0 +1,45 @@
+require File.expand_path('../helper', __FILE__)
+require 'rack'
+
+class RackTest < Test::Unit::TestCase
+  setup do
+    @foo = Sinatra.new { get('/foo') { 'foo' }}
+    @bar = Sinatra.new { get('/bar') { 'bar' }}
+  end
+
+  def build(*middleware)
+    endpoint = middleware.pop
+    @app = Rack::Builder.app do
+      middleware.each { |m| use m }
+      run endpoint
+    end
+  end
+
+  def check(*middleware)
+    build(*middleware)
+    assert get('/foo').ok?
+    assert_body 'foo'
+    assert get('/bar').ok?
+    assert_body 'bar'
+  end
+
+  it 'works as middleware in front of Rack::Lock, with lock enabled' do
+    @foo.enable :lock
+    check(@foo, Rack::Lock, @bar)
+  end
+
+  it 'works as middleware behind Rack::Lock, with lock enabled' do
+    @foo.enable :lock
+    check(Rack::Lock, @foo, @bar)
+  end
+
+  it 'works as middleware in front of Rack::Lock, with lock disabled' do
+    @foo.disable :lock
+    check(@foo, Rack::Lock, @bar)
+  end
+
+  it 'works as middleware behind Rack::Lock, with lock disabled' do
+    @foo.disable :lock
+    check(Rack::Lock, @foo, @bar)
+  end
+end