NIS misses email virus??

Hi,

Just installed NIS 2011 after several years using a competitor. I ran a test I've done it the past by emailing myself a "test virus file" from a different web-based account to another account that I access via Thunderbird (and download to my PC). The test(s) were from "GFI E-mail testing" and the file was "viewthis.jpg.vbs (2KB)". (I will try to upload the file as an attachment to this message, with an added txt extension.)

In the past, as soon as the email message was loaded into Thunderbird, my old anti-virus caught and quarantined it. Norton let it through. In addition, when I saved the file to my desktop nothing happened. And when I did a manual scan on the file Noron said it was ok.

Should I be worried? Does Norton even scan incoming mail in Thunderbird (which is not  listed in "Client Integration")? In any case, shouldn't Norton at least detect the file if downloaded?

Thanks for you help.

- Dave