I've been trying to build my first rails app and have gotten stuck on the issue of user authentication. I've found a number of tutorials for using various plug-ins to do this, but so far every single one of them is out-dated, and as a result, broken!

From what I've read, I think Authlogic may be the best fit for me, and I've tried two things:

1) Going through Railscast, episode #160 (which is a tutorial for setting it up) 2) Using Ryan B's nifty_authentication gem with the --authlogic tag

In both cases, I get the following error as soon as I try to do anything with a user:

undefined local variable or method `acts_as_authentic' for #

I believe this is from the User model:

class User < ActiveRecord::Base
  acts_as_authentic
end

I'm sure I've installed the authlogic gem, and I've added

config.gem "authlogic"

to my environment.rb

Any ideas about what's wrong? Anybody know of a complete and up to date tutorial for adding user authentication?