i think the rules are
1) All cj's , tj's and yj's  with mods  need to wave
2) the stock jeeps or  new jeeps are out  unless they wave first
3) zj's  libertys  and the family carries are out because they are all driven by soccer moms UNLESS they have mod's  they wave
 
i stopped waving to non mod's  becuase of all the WTF looks