From my forum post: http://getshopped.org/forums/topic.php?id=20107&replies=5#post-80493
I have the same problem - and yes, each product and product-variation has its shipping weight established as well as its shipping dimensions.
I uploaded a "fresh" shopping cart page as indicated here: http://getshopped.org/forums/topic.php?id=19397
I do *not* have the WPSC Advance Shipping plugin (since that is no longer necessary according to other posts).
Trusted forum posters Greg and Jeff never came back to this post, regarding the same problem: http://getshopped.org/forums/topic.php?id=17583
This problem seems to be ongoing for over *9* months, which is quite troubling. :-(
I'm using 3.8.2 on WP 3.1.2 - any recommendation appreciated!
Sadly - no fix for some basic functionality? Over a million downloads is a scary thought.