On Thu, 7 Dec 1995, David A Wagner wrote:

Tough!? It's trivial for an active attacker, in the stream cipher case. He just xors some bits: no clever cryptanalysis needed. (Or did you mean it's tough to mount an active attack? I agree: that requires significant knowledge or motivation.)

Exactly.. once you have an active attack set up, it's trivial, but setting that up is quite hard. Mark