[chef] Chef nit working after ruby upgrade

[David Montgomery < >]

just upgraded ruby.  Now chef is not working

How do I resolve?

:~$ knife cookbook upload environment -E development
/usr/local/lib/ruby/2.0.0/

rubygems/dependency.rb:296:in `to_specs': Could not find 'chef' (>= 0) among 8 total gem(s) (Gem::LoadError)
    from /usr/local/lib/ruby/2.0.0/rubygems/dependency.rb:307:in `to_spec'
    from /usr/local/lib/ruby/2.0.0/rubygems/core_ext/kernel_gem.rb:47:in `gem'
    from /usr/local/bin/knife:22:in `<main>'