I found a Sean Lennon autograph that I want to buy on ebay, but I wanted to make sure of its authenticity before buying it. Does it look authentic? Here's a link http://cgi.ebay.com/Sean-Lennon-Signed-Autograph-Promo-Lp-Photo-Flat-12-/230436688436?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item...