diff --git a/lib/jekyll/page.rb b/lib/jekyll/page.rb
index 1a46c854..ef7c4d3a 100644
--- a/lib/jekyll/page.rb
+++ b/lib/jekyll/page.rb
@@ -157,7 +157,7 @@ module Jekyll
     end
 
     def uses_relative_permalinks
-      permalink && @dir != "" && !permalink.include?(File.expand_path(@dir, site.source))
+      permalink && @dir != "" && site.config['relative_permalinks']
     end
   end
 end