Setting up Anti-spam, virus modules

[ictsupport]

We have just puchased the extra modules SpamAssassin and Dr Web in the Server-wide black list is possible to add a string to ban all from a specific domain EG: a spam email is sent and is to be added to Server-wide black list [email protected] can i insert *@spamersite.com or *.* what do you suggest and will this stop all unwanted mail coming from spamersite.com.