$ gem install bundler
NotImplementedError: flock unsupported or native support failed to load
                   flock at org/jruby/RubyFile.java:304
    block in read_binary at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems.rb:773
                    open at org/jruby/RubyIO.java:1125
                    open at org/jruby/RubyKernel.java:310
             read_binary at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems.rb:772
              fetch_spec at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/source.rb:145
                    spec at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/resolver/api_specification.rb:76
      add_always_install at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/resolver/installer_set.rb:77
    resolve_dependencies at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/dependency_installer.rb:473
             install_gem at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/commands/install_command.rb:238
   block in install_gems at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/commands/install_command.rb:299
                    each at org/jruby/RubyArray.java:1560
            install_gems at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/commands/install_command.rb:295
                 execute at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/commands/install_command.rb:202
  invoke_with_build_args at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/command.rb:307
            process_args at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/command_manager.rb:168
                     run at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/command_manager.rb:138
                     run at /home/christian/.rvm/rubies/jruby-9.0.3.0/lib/ruby/stdlib/rubygems/gem_runner.rb:54
                   <top> at /home/christian/.rvm/rubies/jruby-9.0.3.0/bin/jgem:21
                    load at org/jruby/RubyKernel.java:957
                   <top> at /home/christian/.rvm/rubies/jruby-9.0.3.0/bin/gem:1