diff --git a/jasmine-headless-webkit.gemspec b/jasmine-headless-webkit.gemspec
index 451e58c..d3bd110 100644
--- a/jasmine-headless-webkit.gemspec
+++ b/jasmine-headless-webkit.gemspec
@@ -23,7 +23,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'jasmine-core'
   s.add_runtime_dependency 'coffee-script'
   s.add_runtime_dependency 'rainbow'
-  s.add_runtime_dependency 'multi_json'
+  s.add_runtime_dependency 'multi_json', '>= 1.2.0'
   s.add_runtime_dependency 'sprockets'
   s.add_runtime_dependency 'sprockets-vendor_gems'
 end
diff --git a/lib/jasmine/headless/spec_file_analyzer.rb b/lib/jasmine/headless/spec_file_analyzer.rb
index f32308d..a7f1ccb 100644
--- a/lib/jasmine/headless/spec_file_analyzer.rb
+++ b/lib/jasmine/headless/spec_file_analyzer.rb
@@ -33,11 +33,11 @@ module Jasmine::Headless
     end
 
     def serialize(data)
-      MultiJson.encode(data)
+      MultiJson.dump(data)
     end
 
     def unserialize(data)
-      MultiJson.decode(data)
+      MultiJson.load(data)
     end
   end
 end
diff --git a/skel/template.html.erb b/skel/template.html.erb
index c00fd84..644dde9 100644
--- a/skel/template.html.erb
+++ b/skel/template.html.erb
@@ -6,7 +6,7 @@
     <script type="text/javascript" src="<%= Jasmine::Headless.root.join('vendor/assets/javascripts/prolog.js') %>"></script>
     <%= files.join("\n") %>
     <script type="text/javascript">
-      if (window.JHW) { HeadlessReporterResult.specLineNumbers = <%= MultiJson.encode(spec_lines) %>; }
+      if (window.JHW) { HeadlessReporterResult.specLineNumbers = <%= MultiJson.dump(spec_lines) %>; }
     </script>
   </head>
   <body>
diff --git a/vendor/assets/javascripts/intense.coffee b/vendor/assets/javascripts/intense.coffee
index 0e6abfd..f344f78 100644
--- a/vendor/assets/javascripts/intense.coffee
+++ b/vendor/assets/javascripts/intense.coffee
@@ -11,16 +11,16 @@ window.Intense = {
   methods:
     foreground: (color) ->
       if Intense.useColors
-        "\x33[3#{Intense.colors[color]}m#{this}\x33[0m"
+        '\x1b' + "[3#{Intense.colors[color]}m#{this}" + '\x1b' + "[0m"
       else
         this
     bright: ->
       if Intense.useColors
-        "\x33[1m#{this}\x33[0m"
+        '\x1b' + "[1m#{this}" + '\x1b' + "[0m"
       else
         this
   useColors: true
-  moveBack: (count = 1) -> "\x33[#{count}D"
+  moveBack: (count = 1) -> '\x1b' + "[#{count}D"
 }
 
 for method, code of Intense.methods