[fetchmail]bouncing mail

Hi,

I use fetchmail to get mail from multidrop mailbox at  ISP
users have different e-mail and local adresses and i map them in 
.fetchmailrc
All mail that have adresees not listed in the map and don't exist on 
the local mailserver are forwarded to postmaster
is it possible to bounce it to the senders?
there is no "set no bouncemail" option in my .fetchmailrc

meeling for help
Alexander Suslov