NoMethodError (undefined method `+' for nil:NilClass)

[acatighera]

I get this exception when using:
thin (1.2.7)
subdomain-fu (0.5.4)
Karmic 9.10

NoMethodError (undefined method +' for nil:NilClass): /usr/lib/ruby/gems/1.8/gems/subdomain-fu-0.5.4/lib/subdomain-fu.rb:132:incurrent_subdomain'
/usr/lib/ruby/gems/1.8/gems/subdomain-fu-0.5.4/lib/subdomain_fu/routing_extensions.rb:27:in extract_request_environment' thin (1.2.7) lib/thin/connection.rb:76:inpre_process'
thin (1.2.7) lib/thin/connection.rb:74:in catch' thin (1.2.7) lib/thin/connection.rb:74:inpre_process'
thin (1.2.7) lib/thin/connection.rb:57:in process' thin (1.2.7) lib/thin/connection.rb:42:inreceive_data'
eventmachine (0.12.10) lib/eventmachine.rb:256:in run_machine' eventmachine (0.12.10) lib/eventmachine.rb:256:inrun'
thin (1.2.7) lib/thin/backends/base.rb:57:in start' thin (1.2.7) lib/thin/server.rb:156:instart'
thin (1.2.7) lib/thin/controllers/controller.rb:80:in start' thin (1.2.7) lib/thin/runner.rb:177:insend'
thin (1.2.7) lib/thin/runner.rb:177:in run_command' thin (1.2.7) lib/thin/runner.rb:143:inrun!'
thin (1.2.7) bin/thin:6
/usr/bin/thin:19:in `load'
/usr/bin/thin:19

[jseifer]

Try checking your tld_sizes config. Having the correct values in there fixed this for me.