From: Scott McGrath [mailto:mcgrath@fas.harvard.edu]

No answer on that one, However Mac OS X also includes a built in firewall.

On the configuration angle, the Microsoft ICF (Internet Connection Firewall) blocks everything by default.

I just worked on a friends computer last night. The XP ICF firewall was on, and it did not stop the bug.. I want to test that in a lab environment though...