[Exim] Help !

Hi !

    I am trying to solve the following problem . . running exim

I have setup a domain for ETRN use , the client normally would send a etrn
command to release the spool files and mail . This particular client does
not want to send etrn commands but wants our server to poll the given IP
address and send mail on each poll .

How do I get my machine to poll the clients server and send on mail to his
server ??

Any help would be appreciated .

Regards

Sean