title: Quote Item option get lost after editing one item
body: <p>I hope someone can help me...</p>
  
  <p>The goal is to put products separated to the cart. So if 2 products with the same ID are in the cart, they should be shown and handle seperatly and not as one product/item with the qty 2.</p>
  
  <p>To achieve this I use quote item options and events.</p>
  
  <p>Event: checkout_cart_product_add_after 
  Code: </p>
  
  <pre><code>     $quoteItem-&gt;addOption(new Varien_Object(
         array(
              'product' =&gt; $quoteItem-&gt;getProduct(),
              'code' =&gt; 'unique_id',
             'value' =&gt; $uniqueId
        )
    ));
  </code></pre>
  
  <p>I also tried the same using addional_options:</p>
  
  <pre><code>   $additionalOptions = array(
              array(
                  'code'  =&gt; 'unique_id',
                  'label' =&gt; 'Uniaue ID',
                  'value' =&gt; $uniqueId
              )
          );
      $quoteItem-&gt;addOption(
              array(
                  'code'  =&gt; 'additional_options',
                  'value' =&gt; serialize($additionalOptions),
              )
          );
  </code></pre>
  
  <p>After that - everything works fine. The options are shown in the cart and they were stored into the database (sales_flat_quote_item_option) and they all have their own item-id.</p>
  
  <p>But if I edit one product and put it again into the cart - the addional options get lost, they are no longer in the database... This affects all products with the same ID in the cart...</p>
  
  <p>It will be nice, if someone can help me...</p>