diff --git a/examples/sys.config b/examples/sys.config
index 8814893..8ad9bdf 100644
--- a/examples/sys.config
+++ b/examples/sys.config
@@ -8,5 +8,7 @@
 
         {origin_host, "hss.localdomain"},
         {origin_realm, "localdomain"},
-        {vendor_id, 0}
+        {vendor_id, 0},
+        % Append default APN to diameter
+        {append_default_apn, "false"}
 ]}].
diff --git a/src/server_cb.erl b/src/server_cb.erl
index fc8e397..709ef44 100644
--- a/src/server_cb.erl
+++ b/src/server_cb.erl
@@ -136,6 +136,22 @@ gsup_pdp2dia(GsupPdpInfo) ->
 						 'Pre-emption-Vulnerability'=1}
 	}).
 
+-spec gen_default_apn(integer()) -> #'APN-Configuration'{}.
+gen_default_apn(ContextIdentifier) ->
+	#'APN-Configuration'{'Context-Identifier' = ContextIdentifier,
+			     'PDN-Type' = ?PDN_TYPE_DEFAULT,
+			     % The EPS-Subscribed-QoS-Profile AVP and the AMBR AVP shall be present in the
+			     % APN-Configuration AVP when the APN-Configuration AVP is sent in the
+			     % APN-Configuration-Profile AVP and when the APN-Configuration-Profile AVP is
+			     % sent within a ULA (as part of the Subscription-Data AVP).
+			     'EPS-Subscribed-QoS-Profile' = ?EPS_QOS_DEFAULT,
+			     'AMBR' = #'AMBR'{'Max-Requested-Bandwidth-UL' = 100000000,
+					      'Max-Requested-Bandwidth-DL' = 100000000},
+			     % The default APN Configuration shall not contain the Wildcard APN (see 3GPP TS
+			     % 23.003 [3], clause 9.2); the default APN shall always contain an explicit APN
+			     'Service-Selection' = "*"
+			    }.
+
 -spec gsup_pdp2dia_apn('GSUPPdpInfo'()) -> #'APN-Configuration'{}.
 gsup_pdp2dia_apn(GsupPdpInfo) ->
 	#'APN-Configuration'{'Context-Identifier' = maps:get(pdp_context_id, GsupPdpInfo),
@@ -275,7 +291,18 @@ handle_request(#diameter_packet{msg = Req, errors = []}, _SvcName, {_, Caps}) wh
 									  'PDP-Context'=PdpContexts},
 
 					% build the APN-Configuration-Profile
-					ApnCfgList = lists:map(fun gsup_pdp2dia_apn/1, PdpInfoList),
+					ApnCfgList2 = lists:map(fun gsup_pdp2dia_apn/1, PdpInfoList),
+					% append default apn
+					AppendDefaultApn = application:get_env(osmo_dia2gsup, append_default_apn, "true"),
+					case AppendDefaultApn of
+						"true" ->
+							LastApn = lists:last(ApnCfgList2),
+							ApnCfgList = ApnCfgList2 ++ [gen_default_apn(LastApn#'APN-Configuration'.'Context-Identifier' + 1)];
+						_ ->
+							ApnCfgList = ApnCfgList2
+					end,
+					lager:info("ApnCfgList: ~p~n", [ApnCfgList]),
+
 					FirstApn = lists:nth(1, ApnCfgList),
 					DefaultCtxId = FirstApn#'APN-Configuration'.'Context-Identifier',
 					ApnCfgProf = #'APN-Configuration-Profile'{'Context-Identifier' = DefaultCtxId,