How can I ban spam email from trafficmagnet.net, please...

These idiots continue to spam the hell out of my clients and myself. I have sent numerous requests for them to stop, tried to find a number and of course there are unlisted, their domain name whois shows nothing and I am getting sick of this crap...

If someone could please tell me how I can ban or reject any email coming from their domain I would greatly appreciate it!

I'm using a RaQ3.

--------

Head Office, United States:
TrafficMagnet
PDHOST, Inc.
2033 Gateway Place
San Jose, CA 95110
USA

Regional Head Office, Asia-Pacific:
TrafficMagnet
Robinson Road Post Office
Locked Bag SVC No.6
Singapore 908186

Fax:
For customers within the US: 1-877-520-8596 (toll-free) or
for customers outside the US: +65-324-3198

login to your control panel.

goto administrator(i think)

find the email server ... click parameters ... then add the domain to the list of domains you want to reject emails from.