How can you be certain that the PR is not passed to the pages in your case? You may note 2 important points here -
1. PR scale 1 to 10 is not linear. It is highly exponential.
2. Google servers need to calculate and ‘store’ incoming PR value for each page. So a freshly created link may not show passed PR value as Google does not calculate PR in real-time. However, in the next indexing update, it will show up the value. While Google shows the PR in integer format, actual value may be stored in several decimals. You can never know how much that has increased until you see the integer number jump.