diff --git a/lib/slim-rails.rb b/lib/slim-rails.rb
index e4c3e56..2ffcb0d 100644
--- a/lib/slim-rails.rb
+++ b/lib/slim-rails.rb
@@ -4,7 +4,7 @@
 module Slim
   module Rails
     class Railtie < ::Rails::Railtie              
-      if ::Rails.version.to_f >= 3.1
+      if ::Rails.version.to_s >= '3.1'
         config.app_generators.template_engine :slim        
       else
         config.generators.template_engine :slim