I sent the below note to my sons psychologist and she said she will address "sensory seeking behavior"... have you had this come up with your children? I always thought he was just very affectionate but it has been getting more and more lately.
... "DS has a tendency to be really touchy with people around him, not just adults. Where some kids might have an aversion to contact, DS seems to need it. It is getting to the point of being inappropriate and other kids don't like it. Not that he touches anybody inappropriately, just doesn't seem to know when it is ok. We have been talking to him about using his words instead of his hands. It's hard though because he just craves the contact."