Based on these screencaps from The Man Behind the Curtain, don't they look exactly alike? I am still going with the theory that the island exists in the past. Maybe in a Terminator-like twist, Jacob sent for Locke to make Jacob's existence possible? Also, I highly doubt that Ben would have brought Locke to Jacob if he totally didn't want to. Ben is a con-man, just like Sawyer, and the Big Con or whatever it's called was explained in a Sawyer flashback to be "getting the mark to ask you to do something and getting the mark to think that it was his own idea". Locke blew up the submarine for Ben on the same type of con. Now, he has been brought to Jacob by Ben, who makes it seem to Locke like it's Locke's idea.
I have no idea what the significance of any of that is. I just had to download it.