You should be able to get rescheduled with not much trouble. Be apologetic and make it clear that you're not trying to get out of your civic duty to sit on a jury. If you want to make sure you're not selected, wear a Malcolm X t-shirt and answer any question with the phrase "that's what they want you to think." (I'm kidding, of course. That WOULD get you in trouble). Good luck!
As has been said, call the number on your summons and explain your situation. You should have little difficulty getting rescheduled and putting this matter behind you.
Nothing said here shall be construed as legal advice. I can not effectively advise about your case without knowing all the facts. Additionally, my response does not create an attorney-client relationship. If you require further assistance, please contact an attorney privately.