Well at least you are sorted with a decent antivirus then....,
If it comes with Pc-cillin internet security (its a 1 month trial), then speak to the guy in the shop, and tell him some [email]bull@)#$*(#@[/email] story of you have software that wont work with internet security... and ask him if he can just copy the installation files from an older version of pc-cillin(2002) to the computer... (thats the one with the 1 year free)....
there are always ways to get past that....
but what i could find on the internet, it comes with the right version of pc-cillin <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />
Asus product guide look at the bottom of the page