To run the unit tests, you will need the sqlite3-ruby (1.2.1) gem.

You must also checkout/export Rails' active support and active record to
vendor like this:
 svn co http://dev.rubyonrails.org/svn/rails/branches/1-2-stable/activesupport vendor/activesupport
 svn co http://dev.rubyonrails.org/svn/rails/branches/1-2-stable/activerecord vendor/activerecord