Unfortunately, this will be a regular feature on this site, as new and potentially dangerous virus/worms emerge. The latest is Beagle
and their various variants.
Beagle is particularly annoying, as it expertly forges the infected email as if it comes from your ISP, or in some cases, this site. Remember that most infected emails use forged headers (fake "from" or "reply-to" fields), so it does not indicate that our servers are infected (it's Linux anyway, so 99% of worms/virii won't affect it).
Netsky is also a sneaky bastard, as I've already had to help someone remove it from their computer.
For free anti-virus/firewall software download links and tips on how to avoid infection, please head on to this forum thread