superclass mismatch for class SQLite3Adapter in Rails 4.0.0.beta1

I was migrating my app to Rails 4.0.0.beta1 and some of my tests happened to be failing with:

     TypeError:
       superclass mismatch for class SQLite3Adapter
     # blah-blah/acts_as_fu/lib/acts_as_fu/base.rb:17:in `connect!'

It looks like the SQLite3Adapter is no longer autoloaded. Adding a require at the top of base.rb seems to fix the issue. 

Hope this is at least a bit useful. :)