Rails [3.1.0.rc1] webrick freeze on http 500 error

since I installed rails 3.1.0, when some bugs occur, Webrick freezes for a couple of minutes when some bugs occur (not all bugs, apparently the 500 ones).

My gemfile looks like this:

source 'http://rubygems.org'

gem "rails", "3.开发者_开发知识库1.0.rc1"

#Asset template engines
gem 'sass'
gem 'coffee-script'
gem 'uglifier'
gem 'jquery-rails'

gem "simple-navigation"
gem 'ranked-model' #, :git => 'git@github.com:harvesthq/ranked-model.git'
gem 'formtastic'
gem 'validation_reflection'
gem "paperclip", "~> 2.3"
gem 'devise'
gem 'heroku'
gem "aws-s3"
gem "scoped_search"
gem "meta_search", :git => 'git://github.com/ernie/meta_search.git'
gem "kaminari"

group :production do
  gem "pg", "~> 0.11.0"
  gem 'therubyracer-heroku', '0.8.1.pre3'
  gem 'exception_notification', :require => 'exception_notifier'
end

group :development, :test do
  gem 'mysql2'
end

require 'csv'

I'm on Mac OS X 10.6.7.

Can anyone help me on this? Thanks,

Nicolas

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Try using mongrel, or another dev server such as unicorn. Just add it to your gemfile

gem 'mongrel'