Ruby on Rails

Hello, I'm working to install Rails 3 (pre) on my Mac, from the Rails
blog post it says to run:

gem install rails --pre

After running that command I get the following errors:

WARNING: Installing to ~/.gem since /Library/Ruby/Gems/1.8 and
/usr/bin aren't both writable.
WARNING: You don't have /Users/myusername/.gem/ruby/1.8/bin in your
PATH,
gem executables will not run.
ERROR: Error installing rails:
activemodel requires builder (~> 2.1.2, runtime)

was there a step required before running the install that wasn't
mentioned on the blog post?
http://weblog.rubyonrails.org/2010/8/24/rails-3-0-release-candidate-2

Thanks

--
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-talk@googlegroups.com.
To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.