My blog recently jumped from a PR0 to a PR3 in the latest PR update. The homepage is PR3; most of the subpages and posts are PR1. I checked this using SEO Quake, Scrapebox, prchecker.info, and several other free PR checking websites that I won't name here. Every single tool I've used says my blog is a PR3. I should also note that my backlinks are quality and strictly white hat. I recently started applying to advertising networks that offer paid reviews and sponsored posts to bloggers. I've received multiple rejection letters with the reason "Google Page Rank 0" on all of them. I don't understand why this is happening. What the hell are they doing or looking at that they think my blog is a PR0? Is there anything I can do to fix this? Is there any to politely say, "Um, please check again"? I doublechecked my PR one more time before posting this. Still a 3. Any advice would be greatly appreciated.