Your social networking account is being targetted by destructive new viruses, which sneakily invade your computer by sending messages supposedly from your friends. Or the people you added as 'friends' to look more popular. Win32.Koobecaf.a attacks MySpace users, if there are any left, by sending malicious content to their accounts. Similarly, Win32.Koobecaf.b (they'll have to come up with more catchy names if they want to make it big) does the same on Facebook, in message format, meaning it's even more irritating than getting 23 'Which Spice Girl are you?' application requests each week.