title: magento show "Sign up to get notified when this product is back in stock" link for simple-associated products
body: <p>How can we display the "Sign up to get notified when this product is back in stock" link for  associated products of a configurable product. </p>
  
  <p>Say, we have a T-Shirt (a configurable product) and we sell it in 3 sizes - Medium, Large and Xtra-Large (simple - associated products).</p>
  
  <p>When the Large size goes out of stock, how can we make user subscribe for it for notification when it is back in stock.</p>
  
  <p>Please note I have already set this setting in admin:</p>
  
  <pre><code>System &gt; Configuration &gt; Catalog &gt; Allow Alert When Product Comes Back in Stock - Yes
  </code></pre>
  
  <p>I noticed that the url for this alert is like (it is for one of the simple products in my store):</p>
  
  <pre><code>http://localhost/mystore/index.php/productalert/add/stock/product_id/1/[some key]/[some key],,/
  </code></pre>
  
  <p>Is there any way we can call this url directly, passing the product id of our associated product in question? If so, what about those keys at the end of the url?</p>
  
  <p>please guide.</p>
  
  <p>thanks</p>