foreman &passenger —can’t activate rack (~> 1.1.0,runtime),already activated rack-1.3.1

I was getting the lovely error:

can’t activate rack (~> 1.1.0,runtime),already activated rack-1.3.1

After racking (no pun intended) my brain and searching for a while,I found a working solution.

What I ended up having to do was edit /home/foreman/vendor/rails/actionpack/lib/action_controller.rb Around line #34,it reads

gem ‘rack’,‘~> 1.1.0′

All I did was [...]