Ah, now I see it. ;) apparently it was rated X in UK originally, so it's probably a lobby card made for UK cinemas, yeah it's weird but we're talking about the country who put Sam Raimi in court for The Evil Dead in the eighties so it's not that hard to believe, 15 is the UK video rating, erri_wan.
ChainsawAsh-- the lobby card we're talking about is linked in his post.