--- a/Gemfile
+++ b/Gemfile
@@ -141,7 +141,7 @@
 gem 'redcarpet', '~> 3.4'
 gem 'commonmarker', '~> 0.17'
 gem 'RedCloth', '~> 4.3', '>= 4.3.2'
-gem 'rdoc', '~> 4.2'
+gem 'rdoc', '>= 4.2'
 gem 'org-ruby', '~> 0.9.12'
 gem 'creole', '~> 0.5.0'
 gem 'wikicloth', '0.8.1'