Drupal - Ubercart - USPS Shipping price-per-unit

This is sort of a last resort for me. I've posted a few things over at ubercart.org and haven't heard back anything, so I figured I would ask here. In any event, I'm running drupal 6 with the latest dev release of ubercart (upgraded from 2.4). I'm using 开发者_Go百科the USPS shipping module, but it doesn't seem as if the amount of products added to the cart affects the shipping cost. For example, if I add 1 of product 1 to the cart, the shipping is $5.20. If I had 1000 of product 1 to the cart, it's still $5.20. I tried scouring the ubercart.org forums and google, I found some posts, but they were from 2008 and said that changes in regards to this have been since committed, so I'm at a loss.

Can anyone help me? Or point me to a thread that I may have missed? Thanks a lot in advance!