When I run "rake db:migrate", the following errors occurred:
undefined method status_code' for class
ActionDispatch::ShowExceptions'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/core_ext/module/aliasing.rb:32:in alias_method'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/core_ext/module/aliasing.rb:32:in
alias_method_chain'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/will_paginate-3.0.2/lib/will_paginate/railtie.rb:40:in block in <module:ShowExceptionsPatch>'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/concern.rb:114:in
class_eval'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/concern.rb:114:in append_features'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/will_paginate-3.0.2/lib/will_paginate/railtie.rb:28:in
include'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/will_paginate-3.0.2/lib/will_paginate/railtie.rb:28:in setup_actioncontroller'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/will_paginate-3.0.2/lib/will_paginate/railtie.rb:14:in
block (2 levels) in class:Railtie'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/lazy_load_hooks.rb:38:in instance_eval'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/lazy_load_hooks.rb:38:in
execute_hook'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/lazy_load_hooks.rb:28:in block in on_load'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/lazy_load_hooks.rb:27:in
each'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/lazy_load_hooks.rb:27:in on_load'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/will_paginate-3.0.2/lib/will_paginate/railtie.rb:13:in
block in class:Railtie'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/initializable.rb:30:in instance_exec'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/initializable.rb:30:in
run'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/initializable.rb:55:in block in run_initializers'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/initializable.rb:54:in
run_initializers'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/application.rb:215:in initialize!'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/railtie/configurable.rb:30:in
method_missing'
/Users/Bruce/RoR/ShareAllTech/config/environment.rb:5:in <top (required)>'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:228:in
require'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:228:in block in require'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:213:in
load_dependency'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:228:in require'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/application.rb:189:in
require_environment!'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.0/lib/rails/application.rb:249:in block in run_tasks_blocks'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/bin/ruby_noexec_wrapper:14:in
eval'
/Users/Bruce/.rvm/gems/ruby-2.0.0-p247/bin/ruby_noexec_wrapper:14:in `