need help configuring hosts.deny

[Sebastiaan <sebas@sacred-key.org>]

Hi,

I have reason to belive that my computer is used as a relay host for
spam. Walking through the logs, I found one ip number which has no ip
name, but it connects the computer every hour or so and sends some mail.

I want to block this address, but I have not succeeded in configuring the
hosts.deny file correctly. This is what I have:

hosts.allow: empty
hosts.deny:
ALL: 1.2.3.4
ALL: PARANOID

where 1.2.3.4 is the spammers' address. I want to deny him smtp access (or
all access to this machine).

I tried to do this with my own ip, but I was still able to connect to port
25. Telnet access was forbidden however.

I use Postfix as maildaemon.

Thanks in advance,
Sebastiaan