Auth has changed a little bit: radius_www_authorize has been replaced by radius_www_authenticate. www_challenge has been removed and now you should use append_to_reply with a "variable" called $digest_challenge that is created id the radius_ww_authenticate fails (user not auth). So replace your code: For the next lines: if (!radius_www_authenticate("$fd.digest_realm")) { if ($digest_challenge) { append_to_reply("%$digest_challenge"); } sl_send_reply("401", "Unauthorized"); drop; } Depending on where the auth is placed you should use 401 or 407 response code. Hope it helps, Samuel.