Loading nokogiri on Rubinius fails

gistfile1.txt

{17:27}[rbx-head]~/code/VoIP/adhearsion/punchblock@develop✗✗✗ ben% gem install nokogiri
Invalid gemspec in [/Users/ben/Developer/.rvm/gems/rbx-head/specifications/looksee-1.0.3.gemspec]: Illformed requirement ["#<YAML::Syck::DefaultKey:0x49d0c> 0.3.0"]
Invalid gemspec in [/Users/ben/Developer/.rvm/gems/rbx-head/specifications/looksee-1.0.3.gemspec]: Illformed requirement ["#<YAML::Syck::DefaultKey:0x49d0c> 0.3.0"]
Building native extensions.  This could take a while...
Successfully installed nokogiri-1.5.0
1 gem installed
{17:27}[rbx-head]~/code/VoIP/adhearsion/punchblock@develop✗✗✗ ben% irb
Invalid gemspec in [/Users/ben/Developer/.rvm/gems/rbx-head/specifications/looksee-1.0.3.gemspec]: Illformed requirement ["#<YAML::Syck::DefaultKey:0x49d0c> 0.3.0"]
'looksee/shortcuts' is deprecated; please require 'looksee' instead.
>> require 'nokogiri'
LoadError::InvalidExtensionError: Could not open library /Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri/nokogiri.bundle - dlopen(/Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri/nokogiri.bundle, 10): Symbol not found: _rb_external_str_new_with_enc
   from Rubinius::NativeMethod.load_extension at kernel/common/native_method.rb:26
   from Rubinius::CodeLoader#load_library at kernel/delta/codeloader.rb:181
   from Rubinius::CodeLoader#require at kernel/common/codeloader.rb:46
   from Rubinius::CodeLoader.require at kernel/common/codeloader.rb:148
   from Kernel(Object)#gem_original_require (require) at kernel/common/kernel.rb:672
   from Kernel(Object)#require at /Users/ben/Developer/.rvm/rubies/rbx-head/lib/rubygems/custom_require.rb:29
   from Object#__script__ at /Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri.rb:27
   from Rubinius::CodeLoader.require at kernel/common/codeloader.rb:152
   from Kernel(Object)#gem_original_require (require) at kernel/common/kernel.rb:672
   from Kernel(Object)#require at /Users/ben/Developer/.rvm/rubies/rbx-head/lib/rubygems/custom_require.rb:32
   from { } in Object#irb_binding at (irb):1
   from Rubinius::BlockEnvironment#call_on_instance at kernel/common/block_environment.rb:72

Caused by:
LoadError: Could not open library /Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri/nokogiri.bundle - dlopen(/Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri/nokogiri.bundle, 10): Symbol not found: _rb_external_str_new_with_enc
   from FFI::DynamicLibrary#initialize at kernel/platform/library.rb:253
   from Rubinius::NativeMethod.load_extension at kernel/common/native_method.rb:24
   from Rubinius::CodeLoader#load_library at kernel/delta/codeloader.rb:181
   from Rubinius::CodeLoader#require at kernel/common/codeloader.rb:46
   from Rubinius::CodeLoader.require at kernel/common/codeloader.rb:148
   from Kernel(Object)#gem_original_require (require) at kernel/common/kernel.rb:672
   from Kernel(Object)#require at /Users/ben/Developer/.rvm/rubies/rbx-head/lib/rubygems/custom_require.rb:29
   from Object#__script__ at /Users/ben/Developer/.rvm/gems/rbx-head/gems/nokogiri-1.5.0/lib/nokogiri.rb:27
   from Rubinius::CodeLoader.require at kernel/common/codeloader.rb:152
   from Kernel(Object)#gem_original_require (require) at kernel/common/kernel.rb:672
   from Kernel(Object)#require at /Users/ben/Developer/.rvm/rubies/rbx-head/lib/rubygems/custom_require.rb:32
   from { } in Object#irb_binding at (irb):1
   from Rubinius::BlockEnvironment#call_on_instance at kernel/common/block_environment.rb:72

i get this same problem with looksee as well