diff --git a/config.ru b/config.ru
index 05aa8e38e..48ae35298 100644
--- a/config.ru
+++ b/config.ru
@@ -1,10 +1,42 @@
 require 'rubygems'
 require 'rack'
+require 'rack/contrib'
 require 'rack-rewrite'
+require 'mime/types'
 
-use Rack::Rewrite do
-    rewrite %r{(.*)/$},"$1/index.html"
+use Rack::ETag
+module ::Rack
+    class TryStatic < Static
+
+        def initialize(app, options)
+            super
+            @try = ([''] + Array(options.delete(:try)) + [''])
+        end
+
+        def call(env)
+            @next = 0
+            while @next < @try.size && 404 == (resp = super(try_next(env)))[0] 
+                @next += 1
+            end
+            404 == resp[0] ? @app.call : resp
+        end
+
+        private
+        def try_next(env)
+            env.merge('PATH_INFO' => env['PATH_INFO'] + @try[@next])
+        end
+
+    end
 end
-use Rack::Static, :urls => ["/"], :root => "output"
-app = lambda { |env| [404, { 'Content-Type' => 'text/html' }, 'File Not Found'] }
-run app
+
+use Rack::TryStatic, 
+    :root => "output",                              # static files root dir
+    :urls => %w[/],                                 # match all requests 
+    :try => ['.html', 'index.html', '/index.html']  # try these postfixes sequentially
+
+errorFile='output/Scratch/en/error/404-not_found/index.html'
+run lambda { [404, {
+                "Last-Modified"  => File.mtime(errorFile).httpdate,
+                "Content-Type"   => "text/html",
+                "Content-Length" => File.size(errorFile).to_s
+            }, File.read(errorFile)] }