Backlink Question

Let's say a site has a PR6 main page.

If you post a link in a comment, on another page in the site and that other page does not have PR, does the link get credit for a PRO or a PR6?

Thanks

For google every single page is a new (lets call it site). You can easily check that. Lets say you have a WP blog. Put a link to your homepage in the footer. This way every page of your site is a link to your home page. You can later check in yahoo site explorer to see the result that you have an instant 50 or 100 or 15k back links.

About the link I think that the it will be credited for that page (in this case PR0).

It's a page rank 0, but if that page has a link from the homepage then it should have more than a PR0.