RSpec shared_helpers issue

New rails project, installed/configured RSpec 2.3.0, created one model. When I run rake spec, it can't load shared_helpers.rb. Any ideas?

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -S bundle exec rspec "./spec/models/school_spec.rb"
/Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bu开发者_运维百科ndler/shared_helpers.rb:2:in `require': no such file to load -- rubygems (LoadError)
 from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/shared_helpers.rb:2
 from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/setup.rb:1:in `require'
 from /Library/Ruby/Gems/1.8/gems/bundler-1.0.7/lib/bundler/setup.rb:1
rake aborted!
ruby -S bundle exec rspec "./spec/models/school_spec.rb" failed

Solved this by using RVM with Ruby 1.8.7. I was using system ruby prior.