title: Magento. How to reset Checkout Quote reserved Id?
body: <p>Due to an integration with an external system during the checkout I need to reset &amp; provide a new <code>reservedId</code> for the current quote in some situations. I’ve tried several methods, with no success</p>
  
  <p>Does anyone know how to achieve that?</p>
  
  <p>Or, at least, if this is not possible, how can I reset the whole Chekout session without forcing the customer to logout?
  I’ve tried with <code>unsetAll()</code>, <code>clear()</code> &amp; <code>resetCheckout()</code> methods at <code>Mage_Checkout_Model_Session</code>, but they don’t seem to do the trick</p>