title: Create new Rails project with previous rails version
body: <p>The latest version of rails installed on my mac is 3.0.0.beta</p>
  
  <p>gem list returns
  rails (3.0.0.beta, 2.3.5, 2.3.4, 2.3.2, 2.2.2, 1.2.6)</p>
  
  <p>I want to create a new project using version 2.3.5</p>
  
  <p>So I run: <code>rails _2.3.5_ myProject</code></p>
  
  <p>But it returns the following error</p>
  
  <pre><code>$ rails _2.3.5_ photosbackup
  /Library/Ruby/Site/1.8/rubygems.rb:777:in `report_activate_error': RubyGem version error: railties(3.0.0.beta not = 2.3.5) (Gem::LoadError)
      from /Library/Ruby/Site/1.8/rubygems.rb:211:in `activate'
      from /Library/Ruby/Site/1.8/rubygems.rb:1056:in `gem'
      from /usr/bin/rails:18
  </code></pre>
  
  <p>Any idea how I can create a new project using version 2.3.5?</p>
  
  <p>Thanks</p>