I definitely have trouble with eye contact, or atleast, sustained eye contact. For me, looking into someone's eyes is one of the ways I read people. So, in my mind, if they're looking into my eyes, they're trying to read me. I'm very uncomfortable with people "reading" me because most people misread me most of the time. While, I do have changes in tone and inflection when I speak and changes in body language, they seem to have less meaning from me than from NT people. THat is to say, I can be laughing hysterically when I say "I'm serious" about something, and I am actually completely serious.
The primary reason that I'm pretty sure that I don't have a co-morbid autism spectrum disorder or asperger's is the empathy aspect. As opposed to having difficulty reading other people's moods or understanding other people in that aspect, I seem to be hypersensitive to it. For example, when someone says "Try to imagine how you would feel in their situation.", I can do just that with ease and I find that I'm often spot-on with how the person who's actually in that situation feels.
Maybe the eye contact thing isn't so much a "symptom" of Autism or AS, but rather something they often have in common. Like, when I was diagnosed as having ADHD, I was told that my caffiene consumption and cigarette smoking were a couple of "clues" that I have ADHD. I was drinking up to two pots of coffee per day, and I smoked for the purpose of busying my hands versus an actual chemical addiction. I often hold cigarettes or other similarly shaped objects between my fingers and as a teen, I was among those who chewed on the caps of my ink pens.
My apologies. I have a terrible habit of rambling on aimlessly, digressing, and over explaining; especially in the morning (as is the current time of day where I am). That was a really terse way of saying that some people just don't like eye contact as much as others. I don't think that it's necessarily just an aspie thing (so to speak).