diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index <HASH>..<HASH> 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -47,7 +47,7 @@ def each_run
   # Requires supporting files with custom matchers and macros, etc,
   # in ./support/ and its subdirectories including factories.
   ([ENGINE_RAILS_ROOT, Rails.root.to_s].uniq | ::Refinery::Plugins.registered.pathnames).map{|p|
-    Dir[p.join('spec', 'support', '**', '*.rb').to_s]
+    Dir[File.join(p, 'spec', 'support', '**', '*.rb').to_s]
   }.flatten.sort.each do |support_file|
     require support_file
   end
Strings and Pathnames are mixed into one array and we can't call .join on string.