Rails4 Sprockets; Asset logical path has no extension

I recently upgraded to Rails 4, and whilst running my request specs I started getting the following error:

Failure/Error: Unable to find matching line from backtrace Sprockets::ArgumentError: Asset logical path has no extension: europe

Blockquote# /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/asset.rb:36:in initialize' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/base.rb:380:innew' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/base.rb:380:in build_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/index.rb:94:inblock in build_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/caching.rb:58:in cache_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/index.rb:93:inbuild_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/base.rb:287:in find_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/index.rb:61:infind_asset' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/sprockets-2.10.1/lib/sprockets/server.rb:47:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/journey/router.rb:71:inblock in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/journey/router.rb:59:in each' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/journey/router.rb:59:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/routing/route_set.rb:680:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/etag.rb:23:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/conditionalget.rb:25:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/head.rb:11:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/remotipart-1.2.1/lib/remotipart/middleware.rb:27:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/params_parser.rb:27:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/flash.rb:241:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/session/abstract/id.rb:225:incontext' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/session/abstract/id.rb:220:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/cookies.rb:486:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activerecord-4.0.2/lib/active_record/query_cache.rb:36:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activerecord-4.0.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:626:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/callbacks.rb:29:in block in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:373:inrun_515869138317914613_call_callbacks' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:80:in run_callbacks' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/callbacks.rb:27:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/remote_ip.rb:76:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/debug_exceptions.rb:17:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/show_exceptions.rb:30:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/railties-4.0.2/lib/rails/rack/logger.rb:38:incall_app' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/railties-4.0.2/lib/rails/rack/logger.rb:20:in block in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/tagged_logging.rb:67:inblock in tagged' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/tagged_logging.rb:25:in tagged' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/tagged_logging.rb:67:intagged' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/railties-4.0.2/lib/rails/rack/logger.rb:20:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/request_id.rb:21:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/methodoverride.rb:21:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/runtime.rb:17:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/activesupport-4.0.2/lib/active_support/cache/strategy/local_cache.rb:83:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/actionpack-4.0.2/lib/action_dispatch/middleware/static.rb:64:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/sendfile.rb:112:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/railties-4.0.2/lib/rails/engine.rb:511:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/railties-4.0.2/lib/rails/application.rb:97:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/builder.rb:138:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/urlmap.rb:65:in block in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/urlmap.rb:50:ineach' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/urlmap.rb:50:in call' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/capybara-2.2.0/lib/capybara/server.rb:19:incall' # /usr/local/rvm/gems/ruby-1.9.3-p448/gems/rack-1.5.2/lib/rack/handler/webrick.rb:60:in service' # /usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/webrick/httpserver.rb:138:inservice' # /usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/webrick/httpserver.rb:94:in run' # /usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/webrick/server.rb:191:inblock in start_thread'

Is there any way to get Sprockets to accept files without an extension?

Gems: Sprockets: 2.10.1 Rails: 4.0.2