diff --git a/Gemfile b/Gemfile
index dc2b5cc6288e..5bd1264c657f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,6 @@ source "http://rubygems.org"
 
 group :development do
   gem 'rake', '~> 0.9'
-  gem 'rack', '~> 1.4.1'
   gem 'jekyll', '~> 0.12'
   gem 'rdiscount', '~> 1.6.8'
   gem 'pygments.rb', '~> 0.3.4'
@@ -16,4 +15,4 @@ group :development do
   gem 'liquid', '~> 2.3.0'
 end
 
-gem 'sinatra', '~> 1.3.5'
+gem 'sinatra', '~> 1.4.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 02f1073698f4..82c5dcf9b2b9 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -28,8 +28,8 @@ GEM
     pygments.rb (0.3.4)
       posix-spawn (~> 0.3.6)
       yajl-ruby (~> 1.1.0)
-    rack (1.4.5)
-    rack-protection (1.3.2)
+    rack (1.5.2)
+    rack-protection (1.5.0)
       rack
     rake (0.9.2.2)
     rb-fsevent (0.9.1)
@@ -38,13 +38,13 @@ GEM
     sass (3.1.20)
     sass-globbing (1.0.0)
       sass (>= 3.1)
-    sinatra (1.3.5)
-      rack (~> 1.4)
-      rack-protection (~> 1.3)
-      tilt (~> 1.3, >= 1.3.3)
+    sinatra (1.4.2)
+      rack (~> 1.5, >= 1.5.2)
+      rack-protection (~> 1.4)
+      tilt (~> 1.3, >= 1.3.4)
     stringex (1.4.0)
     syntax (1.0.0)
-    tilt (1.3.3)
+    tilt (1.3.7)
     yajl-ruby (1.1.0)
 
 PLATFORMS
@@ -57,11 +57,10 @@ DEPENDENCIES
   jekyll (~> 0.12)
   liquid (~> 2.3.0)
   pygments.rb (~> 0.3.4)
-  rack (~> 1.4.1)
   rake (~> 0.9)
   rb-fsevent (~> 0.9)
   rdiscount (~> 1.6.8)
   rubypants (~> 0.2.0)
   sass-globbing (~> 1.0.0)
-  sinatra (~> 1.3.5)
+  sinatra (~> 1.4.2)
   stringex (~> 1.4.0)
diff --git a/config.ru b/config.ru
index fddabac26521..8e3dc08a771c 100644
--- a/config.ru
+++ b/config.ru
@@ -11,7 +11,7 @@ class SinatraStaticServer < Sinatra::Base
   end
 
   not_found do
-    send_sinatra_file('404.html') {"Sorry, I cannot find #{request.path}"}
+    send_file(File.join(File.dirname(__FILE__), 'public', '404.html'), {:status => 404})
   end
 
   def send_sinatra_file(path, &missing_file_block)