Why does `public_class_method` in an anonymous module make the method public on `Object`?

irb_session

➜ irb
1.9.3p327 :001 > Object.define_method
NoMethodError: private method `define_method' called for Object:Class
	from (irb):1
	from /Users/myron/.rvm/rubies/ruby-1.9.3-p327/bin/irb:16:in `<main>'
1.9.3p327 :002 > m = Module.new do
1.9.3p327 :003 >     public_class_method :define_method
1.9.3p327 :004?>   end
 => #<Module:0x007fd4c493d8e8>
1.9.3p327 :005 > Object.define_method
ArgumentError: wrong number of arguments (0 for 1)
	from (irb):5:in `define_method'
	from (irb):5
	from /Users/myron/.rvm/rubies/ruby-1.9.3-p327/bin/irb:16:in `<main>'
1.9.3p327 :006 > exit