Rome, 24 Nov. (AKI) - A message menacing Western leaders including Italy's prime minister Silvio Berlsuconi appeared on an Islamist website on Thursday. The message - whose authenticity has yet to be verified - threatens to "decapitate" US president George W. Bush, Britain's prime minister Tony Blair, Berlusconi, Japan's prime minister Junichiro Koizumi, and Australian premier John Howard. A section of the message - which reveals a good knowledge of Italian affairs on the part of its author- attacks Berlusconi, announcing: "the plan for his abduction has been laid - it only needs the go-ahead to be given." "Our appointment...