[nixgeek]

Another thing I have noticed is that the official clients like MSN messenger sometimes send links within your IM sessions with someone else about downloading MSN messenger. I use Adium for my IM sessions and when I'm chatting with someone using the official MSN client I get those messages when I'm chatting with them.

Now, I don't know if this is the case with the latest AIM client, but it's possible. Of course, those people that I chat with who use the AIM client on Windows rarely ever update to the latest version of AIM, and thos savvy enough to do so are usually using Trillian or Gaim on the Windows side.

Your friends should be abe to describe to you what the message said. If it said anything about Leopard pictures ("Leopard" being the next major version of OS X which is 10.5, not the animal), then it's possible that you were infected with the Leap-A virus which was announced some time ago. Of course, if ClamXav didn't find anything, then it's probably not that.

Just for safety's sake, if you use Safari for your web browsing head into the preferences and disable the option to open "safe files." While very convenient (and it's always been like this on the Mac OS when downloading files from the web), it can be a major security risk.