Mongrel Crashes in Production

I have been getting this error on the production server after rails was
updated to 2.0.2 and moreover this worked perfectly in the development
mode. This crash occurs when no one is using the app for an hour or so.
This is the error that I get in the logs. (nohup.out file). The
production log doesnt show anything unusual. Please help me out guys.

   1.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/rails.rb:98:in
   2. `reload!': undefined method `reset_application!' for
   3. ActionController::Dispatcher:Class (NoMethodError)
   4. from
   5.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/rails.rb:95:in
   6. `synchronize'
   7. from
   8.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/rails.rb:95:in
   9. `reload!'
  10. from
  11.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/rails.rb:165:in
  12. `reload!'
  13. from
  14.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/rails.rb:178:in
  15. `setup_rails_signals'
  16. from
  17.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/configurator.rb:303:in
  18. `call'
  19. from
  20.
/usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel/configurator.rb:303:in
  21. `join'
  22. from
  23. /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.1.1/bin/../lib/mongrel

Thanks in advance.