Something

on *:JOIN:#:{
  if (%autov) {
    mode $chan +v $nick
  }
  else { 
   halt 
  }
}
on *:text:!avon:#: {
   if ($nick isop $chan || $nick ishop $chan) { 
   set %autov on
    notice $nick autov is now activated
  }
}
on *:text:!avoff:#: {
   if ($nick isop $chan) || ($nick ishop $chan) { 
   set %autov off
    notice $nick autov is now deactvated
  } 
}