title: Implementing case-insensitive passwords with Authlogic
body: <p>I use Authlogic in my app and I want to make things more convenient for my users by ignoring capitalization when I check their passwords (similar to what <a href="http://www.labnol.org/internet/facebook-account-passwords/21241/" rel="nofollow">facebook does</a>)</p>
  
  <p>What's the best way to implement this?</p>
  
  <p>Also, how can I transition existing users to case-insensitive passwords? I.e., I assume I have to resave what is now <code>crypt(password)</code> as <code>crypt(password.downcase)</code>?</p>