anchor.diff:  			#eap_aka_challenge{res = RES, checkcode = CheckCode, mac = MAC}
   					when ((CheckCode == undefined) or (CheckCode == <<>>)) ->
   				EapMessage2 = ocs_eap_codec:aka_clear_mac(EapMessage1),
  -				case ?HMAC_SHA(Kaut, EapMessage2) of
  +				case ?HMACN_SHA(Kaut, EapMessage2) of
   					MAC ->
   						Salt = rand:uniform(16#8000, 16#ffff),
   						<<MSK1:32/binary, MSK2:32/binary>> = MSK,
  
positive.code: 	EapPacket = #eap_packet{code = request, type = ?AKAprime,
  			identifier = NextEapID, data = EapData},
  	EapMessage1 = ocs_eap_codec:eap_packet(EapPacket),
  	Mac = ?HMAC_SHA(Kaut, EapMessage1),
  	EapMessage2 = ocs_eap_codec:aka_set_mac(Mac, EapMessage1),
  	NewStateData = StateData#statedata{request = undefined,
  			eap_id = NextEapID, res = XRES, ck = CKprime, ik = IKprime,
  
negative.code: 	EapPacket = #eap_packet{code = request, type = ?AKAprime,
  			identifier = NextEapID, data = EapData},
  	EapMessage1 = ocs_eap_codec:eap_packet(EapPacket),
  	Mac = ?HMACN_SHA(Kaut, EapMessage1),
  	EapMessage2 = ocs_eap_codec:aka_set_mac(Mac, EapMessage1),
  	NewStateData = StateData#statedata{request = undefined,
  			eap_id = NextEapID, res = XRES, ck = CKprime, ik = IKprime,
  