rem: "The requested URL is not implemented.");
add: "The requested URL or method is not " "implemented by this server.");
context: Ns_ConnReturnNotImplemented(Ns_Conn *conn){    int result;    if (ReturnRedirect(conn, 501, &result)) {	return result;    }    return Ns_ReturnNotice(conn, 501, "Not Implemented",			   "The requested URL is not implemented.");}