gistfile1.txt

$ rvm jruby
$ cat ext/faye_websocket_mask/extconf.rb
unless defined?(RUBY_ENGINE) and RUBY_ENGINE == 'jruby'
  require 'mkmf'
  extension_name = 'faye_websocket_mask'
  dir_config(extension_name)
  create_makefile(extension_name)
end

$ gem build faye-websocket.gemspec 
WARNING:  no description specified
  Successfully built RubyGem
  Name: faye-websocket
  Version: 0.4.3
  File: faye-websocket-0.4.3.gem

$ gem build faye-websocket.gemspec 
WARNING:  no description specified
  Successfully built RubyGem
  Name: faye-websocket
  Version: 0.4.3
  File: faye-websocket-0.4.3.gem

$ gem install faye-websocket-0.4.3.gem 
Building native extensions.  This could take a while...
ERROR:  Error installing faye-websocket-0.4.3.gem:
	ERROR: Failed to build gem native extension.

        /home/turnip/.rvm/rubies/jruby-1.6.7/bin/jruby extconf.rb


Gem files will remain installed in /home/turnip/.rvm/gems/jruby-1.6.7/gems/faye-websocket-0.4.3 for inspection.
Results logged to /home/turnip/.rvm/gems/jruby-1.6.7/gems/faye-websocket-0.4.3/ext/faye_websocket_mask/gem_make.out

$ jruby ext/faye_websocket_mask/extconf.rb

$ echo $?
0