Error using tumblr_client with Rubinius

gistfile1.txt

irb(main):016:0* client.info
NoMethodError: undefined method `[]' on nil:NilClass.
  from kernel/delta/kernel.rb:78:in `[] (method_missing)'
	from /Users/odiab/lib/rbx-2.0.0/gems/gems/tumblr_client-0.8.2/lib/tumblr/request.rb:44:in `respond'
	from /Users/odiab/lib/rbx-2.0.0/gems/gems/tumblr_client-0.8.2/lib/tumblr/request.rb:26:in `get'
	from /Users/odiab/lib/rbx-2.0.0/gems/gems/tumblr_client-0.8.2/lib/tumblr/user.rb:5:in `info'
	from (irb):16
	from kernel/common/block_environment.rb:53:in `call_on_instance'
	from kernel/common/eval.rb:176:in `eval'
	from kernel/common/kernel.rb:440:in `loop'
	from kernel/bootstrap/proc.rb:20:in `call'
	from kernel/common/throw_catch.rb:30:in `catch'
	from kernel/common/throw_catch.rb:8:in `register'
	from kernel/common/throw_catch.rb:29:in `catch'
	from kernel/bootstrap/proc.rb:20:in `call'
	from kernel/common/throw_catch.rb:30:in `catch'
	from kernel/common/throw_catch.rb:8:in `register'
	from kernel/common/throw_catch.rb:29:in `catch'
	from /Users/odiab/lib/rbx-2.0.0/gems/gems/tumblr_client-0.8.2/bin/tumblr:79:in `__script__'
	from kernel/common/kernel.rb:427:in `load'
	from /Users/odiab/lib/rbx-2.0.0/gems/bin/tumblr:23:in `__script__'
	from kernel/delta/code_loader.rb:66:in `load_script'
	from kernel/delta/code_loader.rb:182:in `load_script'
	from kernel/loader.rb:641:in `script'
	from kernel/loader.rb:822:in `main'