sender_host_address in director

Hi,

Thanks to everyone for responding to my last question so quickly.
One more thing and then I promise to stop bugging everyone on the list.

In my private Exim filter file (set up through the forwardfile
directory), I can't seem to make use of the $sender_host_address,
even though the message is being received via SMTP.

Are these values not "passed" onto the director after being received
via SMTP? I'm trying to make my own private ban by IP number, but
it doesn't appear it's being passed into the director.

Thanks!