Rails 3 Installation Hangs at Gem Builder with "unable to convert "\xF1" from ASCII-8BIT to UTF-8"

I followed this tutorial http://pragmaticstudio.com/blog/2010/9/23/install-rails-ruby-mac to install Ruby on Rails on Mac OS X (Lion 10.7).

Everything went fine until I installed Rails with rvm (v. 1.6) when I received the following messages:

Installing RDoc documentation for builder-3.0.0...
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README, skipping
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README.rdoc, skipping**

(Builder version succesfully installed 2.1.2)

and

Installing RDoc documentation for rails-3.0.9...
file 'lib' not found

(Rails 开发者_JS百科version succesfully installed 3.0.9)

I did some research but couldn't find a solution. It looks like I am not the only one to having this problem.

What should I do to fix this?

RubyGems just couldn't change the encoding for the README. Rails should work perfectly fine.