I recently purchased a script called phplinkbid

I am now looking at all websites that are using this script. Many of these sites have a good page rank on the main page. But every site that I have looked at always has a page rank of 0 on every subpage.

Here is an example site: The phpLinkBid Link Directory

If you click on any of the categories at the top they will all have a page rank of 0.

But google will list these pages in their index.

This is the same for every website that is using phplinkbid.

Is there any reason that all subpages receives a page rank of 0?