I am using osx 10.8.2 installed ruby 2.0 and.... got this when trying to run "sudo gem install rails"
$ sudo gem install rails
ERROR: Loading command: install (LoadError)
cannot load such file -- openssl
ERROR: While executing gem ... (NoMethodError)
undefined method `invoke_with_build_args' for nil:NilClass
I had ruby 1.9.x and rails 3.2.x working alright before
You have to install OpenSSL first and recompile ruby again:
RVM:
rvm pkg install openssl
rvm reinstall ruby-2.0.0-p0 --with-openssl-dir=$rvm_path/usr