I am trying to stamp out spam on my server but unfortunately its not working because the spam is actually being sent to another mail server (my ntlworld account) and i have that mail being forwarded. So the connecting server doesnt match any of the servers i am rejecting in my access.db file, because the connecting server is the ntlworld mail server.

How do i approach filtering mail received from another mail server via mail forwarding mechanism, or isnt this possible. Ive had a go at configuring spamassassin but i got stuck with this.