gistfile1.scala

 def createNotFound(f: Failure): LiftResponse = 
    NamedPF((this, Full(f)), LiftRules.uriNotFound.toList) match {
      case DefaultNotFound => Req.defaultCreateNotFound(this)
      case NotFoundAsTemplate(path) => notFoundViaTemplate(path)
      case NotFoundAsResponse(resp) => resp
      case NotFoundAsNode(node) => LiftRules.convertResponse((node, 404),
        S.getHeaders(LiftRules.defaultHeaders((node, this))),
        S.responseCookies,
        this)
    }