If one of your neighbours was studying explosives and booby traps, would you believe this was a legitimate interest?
If he was part of a Royal Engineers mine-clearing team I would.
I think you could apply some of the arguments here to many jobs e.g should we train people to be locksmiths in case they abuse the knowledge etc.
The article does state that they won't be creating anything new, only studying what is already there.
Dr. Ken Barker, Head of the Department of Computer Science, explains that students will not be creating virus de novo, but will examine viruses already in the wild. "That's exactly the kind of misinformation that concerns us," he said. "Nobody here says that we will create new viruses. Some media have reported that students will create new viruses, that is not correct. They're recreating viruses, not creating new viruses."
I'm not sure how else you would train people to write anti-virus software. I can see why people are concerned that it is being offered as an undergraduate course though. The article states it will be a fourth-year course. What age-group are we talking about here - 20/21? Hardly kids anymore surely?
Must think of a witty signature