ubuntu bundle install no such file to load -- rubygems

http://stackoverflow.com/questions/2896485/no-such-file-to-load-rubygems-loaderror

$:~/script/git_tutorial/ruby-getting-started$ bundle install
/usr/lib/ruby/vendor_ruby/bundler/rubygems_ext.rb:8:in `require': no such file to load -- rubygems (LoadError)
from /usr/lib/ruby/vendor_ruby/bundler/rubygems_ext.rb:8
from /usr/lib/ruby/vendor_ruby/bundler.rb:11:in `require'
from /usr/lib/ruby/vendor_ruby/bundler.rb:11
from /usr/bin/bundle:4:in `require'
from /usr/bin/bundle:4
$:~/script/git_tutorial/ruby-getting-started$ sudo update-alternatives --config ruby
[sudo] password : **********
There are 2 choices for the alternative ruby (providing /usr/bin/ruby).

Selection Path Priority Status

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