Possible new virus?

I think there might be a variant on the swen virus doing the rounds as since 8.19 this morning we are getting similar looking emails coming into the office but NAV is not able to scan them and instead of “Attachment something.exe was Deleted for the following Reasons: Virus W32.Swen.A@mm was found” we are now getting “No action was taken on the attachment. Attachment something.exe was Logged Only for the following reasons: Scan Engine Failure (0x80004005). The symantec query results look like its a problem with some compressed files but I’m shortly about to upgrade our email scanning software so we’ll see if we still get it then.