Make sure to Virus Scan befor logging into wow?!

Was doing Naxx 25 on my DK today, only to be kicked off of Wow mid-fight and not be allowed back on, turned out that Blizzard "suspected that there may have been a chance of a key logger, virus, or Trojan on my computer, and my account has been locked for 24 hours." Of course this happens on a Sunday when I can't call them up and be like bitches, turn it back on (they will be getting a call on Monday). Needless to say, this is rather BS and everyone else should watch out to make sure this some how doesn't happen to them. (Oddly enough I scanned my computer and it found nothing out of the ordinary).

After reading the WoW forums, there are others with this problem, too... but nobody can pinpoint what caused their problems, either.