erros na inicializacao projeto Ruby on rails no mac

[jose_ribeiro_neto 0]

como resolver esses erros :

/Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/spec_set.rb:94:in `block in materialize': Could not find i18n-0.7.0 in any of the sources (Bundler::GemNotFound)

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/spec_set.rb:87:in `map!'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/spec_set.rb:87:in `materialize'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/definition.rb:137:in `specs'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/definition.rb:182:in `specs_for'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/definition.rb:171:in `requested_specs'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/environment.rb:18:in `requested_specs'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:13:in `setup'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler.rb:92:in `setup'

from /Library/Ruby/Gems/2.0.0/gems/bundler-1.11.2/lib/bundler/setup.rb:18:in `<top (required)>'

from /Users/joseneto/.rbenv/versions/2.2.3/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'

from /Users/joseneto/.rbenv/versions/2.2.3/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'