It’s time to upgrade to Ruby 1.8.2, folks. Rails 0.10.0 includes various bits that require this version of Ruby, so if you want to run the latest Rails, you’ll have to get on the latest Ruby too. You’ll be glad you updated anyway. Ruby 1.8.2 contains a year’s worth of fixes, additions, and goodies from the Ruby masters. It’s an insult to them if don’t get jiggy with the goods (and Rails developers have other things to worry about that testing across old Ruby versions). Oh, when you upgrade, be sure to patch test/unit.