Rails 3 not loading HAML handler

I'm having some problems with Rails 3 and HAML in my application: for some reason Rails appears not to be loading the handler for dealing with haml files. Every action gives an error message similar to this one:

Template is missing

Missing template contact_search/index with {:formats=>[:html], :handlers=>[:rjs, :rhtml, :rxml, :builder, :erb], :locale=>[:en, :en]} in view paths "/var/www/osphonebook/app/views", "/var/www/osphonebook/vendor/bundle/ruby/1.8/gems/devise-1.3.4/app/views"

Look at the "handlers" options: it does not have :haml...

The thing is that this only happens during production mode on the server set up by my company. On development and test modes it works fine. Also, if I start the application in production mode on my development PC, it works.

Some info about the server:

UPDATE (6/6/2011): upgraded to Ruby 1.9, and it still does not work.

ruby 1.9.2p0 (2010-08-18 revision 29036) [i486-linux]

Gems included by the bundle:
abstract (1.0.0)
actionmailer (3.0.7)
actionpack (3.0.7)
activemodel (3.0.7)
activerecord (3.0.7)
activeresource (3.0.7)
activesupport (3.0.7)
arel (2.0.10)
bcrypt-ruby (2.1.4)
builder (2.1.2)
bundler (1.0.14)
devise (1.3.4)
erubis (2.6.6)
haml (3.1.1)
i18n (0.5.0)
kgio (2.4.1)
mail (2.2.19)
mime-types (1.16)
orm_adapter (0.0.5)
pg (0.11.0)
polyglot (0.3.1)
rack (1.2.3)
rack-mount (0.6.14)
rack-test (0.5.7)
rails (3.0.7)
railties (3.0.7)
rake (0.8.7)
sass (3.1.2)
sqlite3 (1.3.3)
thor (0.14.6)
treetop (1.4.9)
tzinfo (0.3.27)
unicorn (3.6.2)
warden (1.0.4)

If more info is needed, please comment the question, and I'll update it. Thanks for any help.

Try with the gem haml-rails

I've found the problem: I had changed the config/environments/production.rb file to set some personalized code for the ActionMailer. The thing is that I was using the class directly, like this:

ActionMailer::Base.delivery_method = :sendmail
ActionMailer::Base.raise_delivery_errors = true
ActionMailer::Base.charset = "utf-8"

instead of doing like this:

config.action_mailer.delivery_method = :sendmail
config.action_mailer.raise_delivery_errors = true
config.action_mailer.charset = "utf-8"

It appears that using the ActionMailer class directly fired the ActionView loaders, and set all the internal variables, preventing the HAML code to install itself.

After changing the code it worked like a charm.

I found the solution to the 'missing HAML template' error when running in production mode (using Rails 3.2.6 and haml-rails 0.3.4):

In /config/application.rb it has

if defined?(Bundler)
  # If you precompile assets before deploying to production, use this line
  Bundler.require(*Rails.groups(:assets => %w(development test)))
  # If you want your assets lazily compiled in production, use this line
  # Bundler.require(:default, :assets, Rails.env)
end

I changed this to

if defined?(Bundler)
  # If you precompile assets before deploying to production, use this line
  # Bundler.require(*Rails.groups(:assets => %w(development test)))
  # If you want your assets lazily compiled in production, use this line
  Bundler.require(:default, :assets, Rails.env)
end

And now it works.

Does adding

require "haml"

to config/test.rb (and/or development.rb and production.rb) fix this for you?

(Note that I'm using Rails 3.2.2)