Hey, you shouldn't be getting any virus alerts. I think you may be infected with some shit. I don't get the warnings and I'm using Norton also.
Did you check your system for "snakesworld" or "pornno".
Also, run CWShredder and see what happens.
Get it here
http://www.spywareinfo.com/~merijn/downloads.html
If you can't get to this page you're infected. If you can download CWShredder and let me know what happens.
If you get the same shit, I'll dig some more.
Thanks,
Snake