Larry
Another tip. I don't know how much you've been using iCal but when you get the inevitable roster changes, the best way to avoid duplication is to either delete the calendar which contains your roster (Select on sidebar > Edit > Delete) then create a new one before you import the new roster, or select each roster event on your calendar while holding the Shift key down and delete them when they're all highlighted. By doing this, you'll avoid having 2 lots of roster events on one calendar and the associated pain of trying to sort out which is which. When you've deleted the old roster, import the new one and then sync the iPhone again.
STP