I found this blog article just after posting: http://www.darianshimy.com/2009/09/fixing-rails-in-snow-leopard/
I figured I'd try his fix for mongrel, which involves uninstalling the gem and re-installing it. But whenever I try to run "sudo gem install mongrel", the gem process seems to hang. I've had it running for 10 minutes now, and with verbose output turned on, this is all its said: > sudo gem install --verbose mongrel GET http://gems.rubyforge.org/latest_specs.4.8.gz 302 Found GET http://production.s3.rubygems.org/latest_specs.4.8.gz I was able to access http://production.s3.rubygems.org/latest_specs.4.8.gz in my browser and the file downloaded in a few seconds, so I doubt that's the issue. At the same time, I was able to run "sudo gem install thin" and there were no problems. Mark -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-t...@googlegroups.com. To unsubscribe from this group, send email to rubyonrails-talk+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.