求助：We're sorry, but something went wrong.
我是ROR新手，在使用的过程中突然遇到了We're sorry, but something went wrong.的错误。
重启机器后就不再有这个错误，但只要停掉了WEB Server,再次启动后，打开任一页面都会出现这个错误：
Status: 500 Internal Server Error Content-Type: text/html
We're sorry, but something went wrong.
We've been notified about this issue and we'll take a look at it shortly.
日志内容如下：
Session contains objects whose class definition isn't available.Remember to require the classes for all objects kept in the session.(Original exception: uninitialized constant Module::TTree [NameError])C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/cgi_process.rb:161:in `stale_session_check!'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/cgi_process.rb:110:in `session'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:1052:in `assign_shortcuts_without_flash'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/flash.rb:140:in `assign_shortcuts'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:424:in `process_without_filters'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:624:in `process_without_session_management_support'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/session_management.rb:114:in `process'C:/ruby/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:330:in `process'C:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/dispatcher.rb:41:in `dispatch'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/rails.rb:78:in `process'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/rails.rb:76:in `synchronize'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/rails.rb:76:in `process'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:618:in `process_client'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:617:in `each'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:617:in `process_client'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:736:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:736:in `initialize'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:736:in `new'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:736:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:720:in `initialize'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:720:in `new'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel.rb:720:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/configurator.rb:271:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/configurator.rb:270:in `each'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/configurator.rb:270:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/bin/mongrel_rails:127:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/lib/mongrel/command.rb:211:in `run'C:/ruby/lib/ruby/gems/1.8/gems/mongrel-1.0.1-mswin32/bin/mongrel_rails:243C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:488:in `load'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:488:in `load'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:342:in `new_constants_in'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:488:in `load'C:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/commands/servers/mongrel.rb:60C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:495:in `require'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:342:in `new_constants_in'C:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/active_support/dependencies.rb:495:in `require'C:/ruby/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/commands/server.rb:39C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'C:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'script/server:3
