Stop e-mails from reaching your server

We recently have been receiving tons of virus-attached e-mails from this one bogus e-mail address: jan@prodigy.net.mx. I have configured my e-mail server to reject all incoming mails from this server’s IP address. E-mails from this server are not getting through (I think), but I can still see in the error log that they are still attempting to send us crap everyday (probably wasting our bandwidth and server resrouces)! Is there anything we can do (legally) to stop them, or do I just live with it!

Thanks