Paypal has given me this snippet which is a image link that is supposed to open a new window on click to show that an item has been added to the shopping cart, but its not firing the new window up. Here it is:

Code:
<a href="#" onclick="window.open('https://www.paypal.com/cart/add=1&
[email protected]&item_name=oil+change+service&
item_number=1111&amount=29.99&image_url=http%3A//www.davesgarage.com/logo.gif&
return=http%3A//www.davesgarage.com/success.html&cancel_return=http%3A//www.davesgarage.com/cancel.html&
no_note=1','cartwin','width=600,height=400,scrollbars,location,resizable,status');">
<img src="http://images.paypal.com/images/sc-but-01.gif" border="0"></a>
Any ideas?