This is a common frustration of parents during this time of transition--from pre-school to kindergarten.  Please know that you can teach to your son, the benefits of keeping his hands to himself.  He will not frustrate others, and the teacher will have more time to teach the subject rather than be distracted by correcting his behaviors all the time.    
Becoming pro-active in this situation is a good idea.  Ask the help of the teacher and her assistant.  Explain to them, that you are working on appropriate boundaries at home, and you would appreciate their help as they are with your son during the day time hours during the week.  Are they able to notice when he seems to be touching others the most?  Is it in large groups or when they are waiting in line?  Are you able to observe your son in the classroom?  Can you talk with the counselor and ask them to make some observations of your son's behavior?  What are the consequences that your son is earning for his behavior?  Is it a possibility that the teacher can set up some rewards or monitor him more closely in order for her to praise him when he is acting appropriate and keeping his hands to himself?
You can request your child to be moved to a different classroom, but ask yourself what that would achieve?  If you feel the teacher is not being supportive or is teaching your son, then yes, that would be a good idea.  However, what happens if your son continues to 'not keeping his hands to himself'?
 
Remember that with consistency, time and patience: teachers and parents can work together to teach kids a wide variety of skills.
 
Good luck!
Boys Town National Hotline
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