diff --git a/lib/rack/auth/openid.rb b/lib/rack/auth/openid.rb
index 14eeddd..c0cd22f 100644
--- a/lib/rack/auth/openid.rb
+++ b/lib/rack/auth/openid.rb
@@ -1,6 +1,8 @@
 # AUTHOR: blink <blinketje@gmail.com>; blink#ruby-lang@irc.freenode.net
 
 gem 'ruby-openid', '~> 2' if defined? Gem
+require 'rack/request'
+require 'rack/utils'
 require 'rack/auth/abstract/handler' #rack
 require 'uri' #std
 require 'pp' #std
diff --git a/lib/rack/conditionalget.rb b/lib/rack/conditionalget.rb
index e7eb586..7bec824 100644
--- a/lib/rack/conditionalget.rb
+++ b/lib/rack/conditionalget.rb
@@ -1,3 +1,5 @@
+require 'rack/utils'
+
 module Rack
 
   # Middleware that enables conditional GET using If-None-Match and
diff --git a/lib/rack/content_length.rb b/lib/rack/content_length.rb
index 515a654..bce22a3 100644
--- a/lib/rack/content_length.rb
+++ b/lib/rack/content_length.rb
@@ -1,3 +1,5 @@
+require 'rack/utils'
+
 module Rack
   # Sets the Content-Length header on responses with fixed-length bodies.
   class ContentLength
diff --git a/lib/rack/deflater.rb b/lib/rack/deflater.rb
index 7dcc601..2aab14b 100644
--- a/lib/rack/deflater.rb
+++ b/lib/rack/deflater.rb
@@ -1,6 +1,7 @@
 require "zlib"
 require "stringio"
 require "time"  # for Time.httpdate
+require 'rack/utils'
 
 module Rack
 
diff --git a/lib/rack/directory.rb b/lib/rack/directory.rb
index 570edd4..56ee5e7 100644
--- a/lib/rack/directory.rb
+++ b/lib/rack/directory.rb
@@ -1,4 +1,5 @@
 require 'time'
+require 'rack/utils'
 require 'rack/mime'
 
 module Rack
diff --git a/lib/rack/file.rb b/lib/rack/file.rb
index 4bc6198..44f7629 100644
--- a/lib/rack/file.rb
+++ b/lib/rack/file.rb
@@ -1,4 +1,5 @@
 require 'time'
+require 'rack/utils'
 require 'rack/mime'
 
 module Rack
diff --git a/lib/rack/lint.rb b/lib/rack/lint.rb
index e7f805f..c8c4f67 100644
--- a/lib/rack/lint.rb
+++ b/lib/rack/lint.rb
@@ -1,3 +1,5 @@
+require 'rack/utils'
+
 module Rack
   # Rack::Lint validates your application and the requests and
   # responses according to the Rack spec.
diff --git a/lib/rack/session/abstract/id.rb b/lib/rack/session/abstract/id.rb
index 10fa56b..1e4fba3 100644
--- a/lib/rack/session/abstract/id.rb
+++ b/lib/rack/session/abstract/id.rb
@@ -2,6 +2,7 @@
 # bugrep: Andreas Zehnder
 
 require 'time'
+require 'rack/request'
 
 module Rack
 
diff --git a/lib/rack/session/cookie.rb b/lib/rack/session/cookie.rb
index 3dba358..9e1b97a 100644
--- a/lib/rack/session/cookie.rb
+++ b/lib/rack/session/cookie.rb
@@ -1,4 +1,5 @@
 require 'openssl'
+require 'rack/request'
 
 module Rack
 
diff --git a/lib/rack/showexceptions.rb b/lib/rack/showexceptions.rb
index 3fee6ae..d809037 100644
--- a/lib/rack/showexceptions.rb
+++ b/lib/rack/showexceptions.rb
@@ -1,6 +1,7 @@
 require 'ostruct'
 require 'erb'
 require 'rack/request'
+require 'rack/utils'
 
 module Rack
   # Rack::ShowExceptions catches all exceptions raised from the app it