Share Cookies in rails 3.1.3

Hi all,
i am using Rails 3.1.3 and ruby 1.9.3.i need to set the cookies for multiple domain,
Example: test.abc.com and example.abc.com are the two different domain, i need to set the same cookie for the both domain. If user login with test.abc.com can automatically login with example.abc.com

I have tried :
Rails.application.config.session_store :cookie_store, :key => ‘_Admin_Kernel_session’, :domain=>:all
Rails.application.config.session_store :cookie_store, :key => ‘_Admin_Kernel_session’, :domain=>".abc.com"
cookies.permanent.signed[:new_cookie] = {:value => new_value, :domain => “.abc.com”}
cookies[:some_cookie] = {:value => “whatever”, :domain => “.abc.com”, :expires => 1.year.from_now.utc}

        i have tested with  middle-ware to set session domain but no use.

Please could any one tell me how to implement.

Kingston.s

i got the error.Its working now. Its my mistake.