[exim] Accept locally generated bounces and auto-replies

Hi,

Exim is the mail gateway for several Exchange servers and frequently
sends bounce messages to users, such as when they mistype a domain name.
I would like to accept these bounce messages which presently are being
delivered to a folder with all other null sender mail.

I have tried this in the acl rcpt and data but it doesn't work:

accept hosts = 127.0.0.1

The mail is being received from the local exim user as per the received
header and logs this "U=exim P=local"

I am having the same problem is trying to identify auto-replied mail
which ends up in the same null sender folder.

Any ideas? Thanks.

Craig