Necessary party for easements

 what is the position   if some of the servient owners  are not  joined  as parties  to  a   suit  wherein a decalration  of  easmentary  right  of  way is  sought  for ? ,    and  what consequences  would  ensue if  there is  no  pleading   to the  effect that  the  left out  parties  are not  disturbing the plaintiff   in excercising his  right of  way ?   please  cite  decisions  for  and  against  the  point