Rails session_id in URL

Question

I am trying to pass a session_id in a URL with Rails (2.3.1). The passing of the id is working through default_url_options, I am using memcache as a session store and I've set :cookie_only to false in environment.rb

However it still does not seem to work. If I log in successfully, the first page is shown correctly, however when I continue to the next page, the session is lost.

Does anyone know what I might be missing?

Thanks