The BSD license and the law

AlanS2002 writes: "Groklaw is hosting an article by Brendan Scott which looks at what misconceptions exist in regards to the BSD license, from the article "We observe that there exists a broad misconception that the BSD permits the licensing of BSD code and modifications of BSD code under closed source licenses. In this paper we put forward an argument to the effect that the terms of the BSD require BSD code and modifications to BSD code to be licensed under the terms of the BSD license. We look at some possible consequences and observe that this licensing requirement could have serious impacts on the unwary.""