Someone

on *:TEXT:~copy*:#: {
  if ($nick == Javida) {
    /msg $chan $2 will be copied!    
    set %mimic $2
  }
}
on *:text:*:#: {
  if ($nick == %mimic) {
    msg $chan $1-
  }
  else { Halt }
}

on *TEXT:!copy off:#: {
  if ($nick == Javida) {
    /msg $chan %mimic will no longer be copied!    
    unset %mimic
  }
}