title: iPhone: NSHTTPCookie is not saved across app restarts
body: <p>In my iPhone app, I want to be able to reuse the same server-side session when my app restarts. A session on the server is identified by a cookie, which is sent on each request. When I restart the app, that cookie is gone and I can't use the same session anymore.</p>
  
  <p>What I noticed when I used the <code>NSHTTPCookieStorage</code> to look up the cookie I got from the server, is that <code>[cookie isSessionOnly]</code> returns <code>YES</code>. I get the impression that this is why cookies are not saved across restarts of my app. What would I have to do to make my cookie NOT session only? What HTTP headers do I have to send from the server?</p>