/home/sb/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.1/lib/bundler/fetcher.rb:112:in `specs': undefined method `each' for nil:NilClass (NoMethodError)
    from /home/sb/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.1/lib/bundler/source/rubygems.rb:244:in `block in remote_specs'
    from /home/sb/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.1/lib/bundler/source/rubygems.rb:244:in `each'

网上也没有搜到类似的问题，有知道的吗