diff --git a/lib/jekyll/converters/markdown/redcarpet_parser.rb b/lib/jekyll/converters/markdown/redcarpet_parser.rb
index ce4a303d..b7a25c46 100644
--- a/lib/jekyll/converters/markdown/redcarpet_parser.rb
+++ b/lib/jekyll/converters/markdown/redcarpet_parser.rb
@@ -19,7 +19,7 @@ module Jekyll
             end
 
             def add_code_tags(code, lang)
-              code = code.sub(/<pre>/,'<pre><code class="language-' + lang + '">')
+              code = code.sub(/<pre>/, "<pre><code class=\"#{lang} language-#{lang}\">")
               code = code.sub(/<\/pre>/,"</code></pre>")
             end
           end