Rails 2.1.0 and tzinfo plugin

I am upgrading a Rails 1.2.6 app to Rails 2.1.0 that had used tzinfo gem to manage time zones. Time zone support is built into Rails 2.1.0 and is based on the tzinfo gem. However, it is slightly different (I do not know how slightly) and causes a time based test to fail that passes in Rails 2.0.2 (since it did not have Time Zone support, it uses the tzinfo gem and the test works).

If there is an easy way around this problem then that would be excellent. In lieu of that, is there a way that I can coax rails to load the tzinfo gem (freeze it into the vendor directory?) ahead of its built-in timezone support? I might just go with it to production until I figure out an upgrade plan.

Thanks in advance for your time.

Bharat