There's a version of W32/Gibe-F aka SwenA that gets past the virus checker on our mail server at work. My Sophos detects it as it's being downloaded, but reports Access denied. It finally shreds when I look at the attachment directory. The e-mail message is always a Returned Mail message.

This is really nasty, I almost always get two messages that have come from the same source. One is the Microsoft Patch message & our server always catches that one. The second is Returned Mail & always has the virus. I've gotten dozens of them in the past week and a half.