Could it be a case of much ado about nothing? Doug Ross thinks so.  Questions have been raised about the copy posted on the Daily Kos site bore a state seal embossed.

..one of Pamela Geller's readers did some heavy-lifting with Photoshop and discovered what appears to be an embossed seal on the back of Obama's certificate.

I was startled because I had carefully reviewed the image weeks ago and not seen any clue of a signature or embossed seal. I spent some time this morning playing with various graphics settings until I was able to tease a similar image out of the scan.

It certainly appears to be legitimate.