#11 of terror suspects and chimps

I've recently read two articles that, although at first glance very different, are more similar upon inspection.

The first speaks of the very curious case about a prison visit:

Terror Suspect's Brother Accused of "Sinister" Sign Language
http://blog.wired.com/27bstroke6/2007/11/terror-suspects.html

Yahia Megahed is the brother of Youssef Megahed, a "University of South Florida student and terror suspect." He was arrested after being stopped by police in a speeding car in which a box of .22 caliber bullets and some homemade pipe bombs containing explosives material were found. The story follows, then, that during one prison visit, brother Yahia tried to send "sinister messages" to Youssef with sign language and facial expression. Apparently, as seen on the survelliance cameras, Yahia first "cleared the scene" to make sure no one was present, then started raising his eyebrows and "signing" to the camera. Professionals who understand American Sign Language were hired, and they interpreted the hand signals to be signing the letters m,i,g,c,l. The prosecutor, then, used this as further evidence that Youssef shouldn't receive bail, because he was scheming with external agents.

I was very much intrigued by this claim,and wondered if body language could really convey a sense of such sinister intentions as described. So, I found the link to the actual footage caught by the cameras, and watched the scene for myself (y'all should check it out--it's quite amusing):

http://www.myfoxtampabay.com/myfox/pages/Home/Detail?contentId=4557891&version=2&locale=EN-US&layoutCode=VSTY&pageId=1.1.1

What I felt, after watching the clip, was a sense of the absurd. The actions and motions that brother Yahia took was extremely remniscent of my little brother on Skype, who, when sure that no one was around him, would make funny faces into the webcam and spontaneous hand gestures. However, I looked at the case from the perspective of the investigators, who seemed to find something more sinister in these actions when set against the background of the case (potential terroists threat). So then, is there an objective way to interpret body langauge? At what point (and to what extent does this depend on personal biases) does body language cease to be innocent and unpremeditated expression, and instead seem to convey something with much more implicit meaning? What do you guys think? Was Yahia's moment in the spotlight tainted with something darker and more implicit?

In a second case, sign and body language also plays a rather prominent role.

An African Chimpanzee and its Language of Signs
http://www.hindu.com/2007/11/02/stories/2007110257872200.htm

The female chimpanzee, Washoe, was believed to be the first nonhuman who has learned human language. Empirical evidence obtained from experiments showed that when researchers, under a controlled environment, communicated to Washoe using only sign language and minimal facial/body expression/language, she signed back with appropriate answers. However, the interesting part of these results is that both Chomsky and Pinker dispute the accuracy of these interpretations (that Washoe actually acquired human language). Chomsky argued "neural requirements for language developed in humans after the evolutionary split between humans and other primates," while Pinker contested that "primates simply learn to perform certain acts in order to receive rewards, and do not acquire true language."
What intrigues me about Pinker's point is that it sounds very much like a child first learning a language. An infant the age of three surely does not know what "walk" means, but when they're told to "walk" and immediately placed on their feet (and treated afterwards when they do take those first few steps), they begin to associate "walk" with the reward. Thus, they react more to the consequences of the utterance than to the actual definition itself. What then, does this imply about chimps? Can they not also pass the first "perform and reward" stage and eventually move into comprehension. I suppose this brings up the question: is the actual act of learning innate, or can it actually be acquired with deliberate effort? What's your take on this?