title: Rails, Devise, and Mongo - Which versions do I use?
body: <p>I'm currently trying to get a Mongo database running alongside Devise.  I'm using Rails 3.2.2 and Ruby 1.9.3, mongo_mapper 0.11.0, devise 1.1.9, and devise-mongo_mapper 0.0.2.  I've referred to numerous sources online, but they seem to be invariably outdated.</p>
  
  <p>A huge problem I'm facing right now involves devise-mongo_mapper.  With mongod running on the terminal, trying to run the rails server gives me the following:</p>
  
  <pre><code>/usr/local/lib/ruby/gems/1.9.1/gems/devise-1.1.9/lib/devise.rb:193:in `mailer=': undefined method `ref' for ActiveSupport::Dependencies:Module (NoMethodError)
  from /usr/local/lib/ruby/gems/1.9.1/gems/devise-1.1.9/lib/devise.rb:195:in `&lt;module:Devise&gt;'
  from /usr/local/lib/ruby/gems/1.9.1/gems/devise-1.1.9/lib/devise.rb:4:in `&lt;top (required)&gt;'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:68:in `require'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:68:in `block (2 levels) in require'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:66:in `each'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:66:in `block in require'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:55:in `each'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler/runtime.rb:55:in `require'
  from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.0.21/lib/bundler.rb:122:in `require'
  from /home/neilbasu/Desktop/rails_practice_app/onemoremongopractice/config/application.rb:13:in `&lt;top (required)&gt;'
  from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.2/lib/rails/commands.rb:53:in `require'
  from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.2/lib/rails/commands.rb:53:in `block in &lt;top (required)&gt;'
  from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.2/lib/rails/commands.rb:50:in `tap'
  from /usr/local/lib/ruby/gems/1.9.1/gems/railties-3.2.2/lib/rails/commands.rb:50:in `&lt;top (required)&gt;'
  from script/rails:6:in `require'
  from script/rails:6:in `&lt;main&gt;'
  </code></pre>
  
  <p>I checked online and found this could be because my devise isn't updated.  Trying to update it gave me this:</p>
  
  <pre><code>Bundler could not find compatible versions for gem "devise":
    In Gemfile:
      devise-mongo_mapper (&gt;= 0) ruby depends on
        devise (~&gt; 1.1.0) ruby
  
      devise (2.0.4)
  </code></pre>
  
  <p>So basically, the older devise won't work, and the newest version isn't compatible with my current devise-mongo_mapper.  Is there any way around this?  Either a way to get all of these programs working together or a way to not need devise-mongo_mapper at all would be great.</p>