undefined method `mounted_helpers' for devise plugin

hi, initially i used i devise as gem but now i want to use devise plugin in my vender/plugin for my application so i gave rails plugin install GitHub - heartcombo/devise: Flexible authentication solution for Rails with Warden. after giving install plugin it has been downloaded fine,but now while i was trying to run

rails s => Booting WEBrick => Rails 3.0.10 application starting in development on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server Exiting /home/prabhu/clone/aiq26/devise_username/aisleiq/vendor/plugins/devise/ lib/devise/failure_app.rb:14:in `<class:FailureApp>': undefined method `mounted_helpers' for #<ActionDispatch::Routing::RouteSet:0x9d86a2c> (NoMethodError)   from /home/prabhu/clone/aiq26/devise_username/aisleiq/vendor/plugins/ devise/lib/devise/failure_app.rb:8:in `<module:Devise>'   from /home/prabhu/clone/aiq26/devise_username/aisleiq/vendor/plugins/ devise/lib/devise/failure_app.rb:3:in `<top (required)>'   from /usr/local/lib/ruby/gems/1.9.1/gems/devise-1.4.5/lib/devise.rb: 410:in `configure_warden!'   from /usr/local/lib/ruby/gems/1.9.1/gems/devise-1.4.5/lib/devise/ rails/routes.rb:9:in `finalize_with_devise!'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application.rb:128:in `block in reload_routes!'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/lazy_load_hooks.rb:36:in `instance_eval'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/lazy_load_hooks.rb:36:in `execute_hook'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/lazy_load_hooks.rb:26:in `on_load'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application.rb:128:in `reload_routes!'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application.rb:120:in `block in routes_reloader'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/file_update_checker.rb:32:in `call'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/file_update_checker.rb:32:in `execute_if_updated'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application/finisher.rb:51:in `block (2 levels) in <module:Finisher>'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application/finisher.rb:52:in `call'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application/finisher.rb:52:in `block in <module:Finisher>'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ initializable.rb:25:in `instance_exec'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ initializable.rb:25:in `run'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ initializable.rb:50:in `block in run_initializers'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ initializable.rb:49:in `each'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ initializable.rb:49:in `run_initializers'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application.rb:134:in `initialize!'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ application.rb:77:in `method_missing'   from /home/prabhu/clone/aiq26/devise_username/aisleiq/config/ environment.rb:6:in `<top (required)>'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:239:in `require'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:239:in `block in require'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:225:in `block in load_dependency'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:593:in `new_constants_in'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:225:in `load_dependency'   from /usr/local/lib/ruby/gems/1.9.1/gems/activesupport-3.0.10/lib/ active_support/dependencies.rb:239:in `require'   from /home/prabhu/clone/aiq26/devise_username/aisleiq/config.ru:3:in `block in <main>'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ builder.rb:46:in `instance_eval'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ builder.rb:46:in `initialize'   from /home/prabhu/clone/aiq26/devise_username/aisleiq/config.ru:1:in `new'   from /home/prabhu/clone/aiq26/devise_username/aisleiq/config.ru:1:in `<main>'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ builder.rb:35:in `eval'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ builder.rb:35:in `parse_file'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ server.rb:162:in `app'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ server.rb:253:in `wrapped_app'   from /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.2.5/lib/rack/ server.rb:204:in `start'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ commands/server.rb:65:in `start'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ commands.rb:30:in `block in <top (required)>'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ commands.rb:27:in `tap'   from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.0.10/lib/rails/ commands.rb:27:in `<top (required)>'   from script/rails:6:in `require'   from script/rails:6:in `<main>'

above error appears,could any one provide me solution regarding this mounted_helpers

thanks, -pab