rails cookie sourroundings problems

i have rails app sets cookie does route another server once user logged in. however, cookie rails app sets isn't seen server reason. i've attempted sourroundings http_only fake nonetheless i still can't even cookie unless domain same rails app. here's formula i'm controlling set cookie:

cookies[:dev_appserver_login] = 
  { :value => "#{email}:#{nick}:#{admin}:#{hsh}",
    :domain => "webserver-to-redirect-to",
    :expires => 30.days.from_now }

redirect_to session[:dest_url]

if i manually emanate cookie firefox works fine, nonetheless rails does it. any ideas?