diff --git a/actionpack/lib/sprockets/railtie.rb b/actionpack/lib/sprockets/railtie.rb
index c75b7d4de0..88892293b1 100644
--- a/actionpack/lib/sprockets/railtie.rb
+++ b/actionpack/lib/sprockets/railtie.rb
@@ -99,7 +99,7 @@ def compressor.compress(source)
         compressor
       when :yui
         require 'yui/compressor'
-        YUI::JavaScriptCompressor.new(:munge => true)
+        YUI::CssCompressor.new
       else
         sym
       end