'I hate you!' kid, + questions about 'The Infected'

Anyone watch this film with subtitles or captions? I swear, no one seems to notice that the "Infected" child that jumps Jim spoke to him! That caught me off guard. His mouth didn't really move to the dubbed line convincingly, but he definitely said it. It almost looked like they threw that in at the last minute. All the other "zombies" only snarl and roar and puke blood, etc. So this raises some interesting questions! They can talk? If they can talk, isn't it safe to say they still have some intelligence preservered in their brains? If they're intelligent enough and can communicate via speech, is it safe to assume that they can somehow be reached by communicating with non-infected humans?Perhaps with the right drugs (tranquilizers, psychotropics, what have you) induce some form of hypnotherapy, (have them restrained of course) perhaps they can be cured from the disease and gradually conditioned back to humanism after a successful blood transfusion! (Like the original, plot-hole mess of an ending)

Actually, no, I think the director just forgot to edit that out or something. lol

The "I hate you" line was probably an ad lib from the child actor, getting into character and perhaps didn't realize (or wasn't told) the infected cannot talk. But hell, maybe it was an involuntary reflex that some of them have; a reaction to the 'rage' disease and only a short, familiar sentence such as "I hate you" just comes out automatically from a subconscious level. Sounds intelligible, but they in fact have no idea what they're saying. But I wonder what others make of this.

Another quick observation; the zombies (yeah, I'm calling them zombies now, sue me) in the scene at the beginning inside chapel, I noticed they were perfectly calm until Jim showed up and spoke to them. In fact, they appeared to be sleeping! (That scene freaked me out, the way 2 of them stood up VERY suddenly and just stared at Jim with a highly-alerted animalistic frozen expression on their face) they didn't look human, the way their mouths were wide open. Looked like something from a nightmare I once had.)

So anyway...Do you think they sleep? I wonder...Do they eat? I never saw one eat a human, they just tear and attack at people and run frantically at any life form they encounter.

I wonder if the infected ever attack each other or animals or corpses...or even go into other rage-induced pandemoniac actions. Do they only just aim to kill their victims by viscously clawing at them like monkeys in crack? They don't try to eat or rape people? lol This is a whole new breed of zombification, and it's the middle of the night and I brainstorm pointless crap like this when I'm delirious with lack of sleep.

Input! Tell me what you think!