Did you not even bother to visit the website in your kill message? It describes what it is and exactly what to do. There's not much else we can do for you here; DALnet is not associated with these forums.
To clarify though, these akills can happen a lot and may not be your fault-- it could just be a ban set on another hostmask that you just happen to be sharing at that moment in time. If you're sure you don't have any viruses, just wait out the ban as they describe.
