Fake Locke leads the others to the old flight 815 survivors camp. Locke tells everyone that they should get to where they're going by nightfall and to take a moment rest. With a sinister smile on his face he says "Considering what I have planned for you, you're gonna need it."
Later, Ben is sitting alone on the beach when Locke comes over to ask him if everything is alright. Ben says that he was enjoying some along time. Locke points out the Swan hatch door that is sitting behind them. Ben says "It's a door. How about that?" Locke points out that it's the door to the hatch where they first met. Locke asks "Do you mind if I ask you a question?" and Ben sarcastically says "I'm a Pisces."
Locke asks Ben what happened at the cabin when he first took him to meet Jacob. Ben admits that he was talking to an empty chair and was as surprised as Locke when things started flying around the room. Locke asks him why he would go to the trouble of making all of it up. Ben says that he was embarrassed and didn't want Locke to know that he had never seen Jacob. He says "So yes, I lied. That's what I do." Locke accepts his answer and starts to walk away.
Ben stops him by asking "Why do you want me to kill Jacob, John?" Locke uses some of Ben's manipulative tricks on him. Locke says "Because, despite your loyal service to this Island, you got cancer. You had to watch your own daughter gunned down right in front of you. And your reward for those sacrifices? You were banished. And you did all this in the name of a man you'd never even met. So the question is, Ben, why the hell wouldn't you want to kill Jacob?"
Looking back on this scene, this was another tip that Locke was not Locke. Locke has never been a manipulative guy for the most part and he is definitely quite Ben-like during this scene.
It seems now that that cabin scene in season 3 has a totally different meaning than we though it did. If Jacob was not in the cabin, who made things fly around the room and made the man appear in the chair? It would seem that the same entity that is now inhabiting Locke is a likely candidate.
Also, what plans for the others does fake Locke have? Does it involve killing the Ajira passengers or is it something more?