Error installing Rails 3 OS X 10.6

Question

I'm trying to upgrade Rails 3 on OS X 10.6. I currently have gem version 1.8.11. I received this error:

ERROR:  Error installing rails:
    ERROR: Failed to build gem native extension.

        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb
mkmf.rb can't find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/ruby.h

Answer 1

Here is a walk trough that worked for me for updating rails and ruby.

it use RVM which i highly recommend ;-)

updating to Rails 3 on MAC OSX