Issue #7997 has been updated by marcocarvalho (Marco Carvalho). CGI cookie needs CGI/core to run... open "lib/ruby/2.0.0/cgi.rb" and see that cgi/cookie is loaded before cgi/core I think it's not an error, 'cgi/cookie' depends on 'cgi/core'. ---------------------------------------- Backport #7997: undefined method `unescape' for CGI:Class https://bugs.ruby-lang.org/issues/7997#change-37254 Author: nelsnelson (Nels Nelson) Status: Open Priority: Normal Assignee: Category: Target version: $ ruby2.0 -v ./test.rb "_my_app_session_id=e6fafc122f84c2755310d712e5a19320; domain=.my.app.unknown.com; path=/; HttpOnly" ruby 2.0.0dev (2013-02-08 trunk 39161) [x86_64-darwin12.2.0] Parsing cookie string: _my_app_session_id=e6fafc122f84c2755310d712e5a19320; domain=.my.app.unknown.com; path=/; HttpOnly /usr/local/lib/ruby/2.0.0/cgi/cookie.rb:151:in `block in parse': undefined method `unescape' for CGI:Class (NoMethodError) from /usr/local/lib/ruby/2.0.0/cgi/cookie.rb:148:in `each' from /usr/local/lib/ruby/2.0.0/cgi/cookie.rb:148:in `parse' from ./test.rb:7:in `<main>' -- http://bugs.ruby-lang.org/