title: CodeIgniter session timeout issue
body: <p>I’m using CI 2.1.4 and I set</p>
  
  <pre><code>$config['sess_expiration'] = 0;
  </code></pre>
  
  <p>but sometime when I’m in my dashboard I’m unlogged automaticaly by the site…</p>
  
  <p>The context is the following :</p>
  
  <p>I’m using 2 applications for 1 system, but both applications use the same encryption key, session table and the same timeout.</p>
  
  <p>This problem appear when I submit a form then after I pick up session data to add it in the database.</p>
  
  <p>Anyone has an idea ?</p>
  
  <p>Thanks.</p>