after "cat" log now says:

response was invalid[2]: (ISAKMP_N_INVALID_PAYLOAD_TYPE)(1)


Other issue/idea: FRITZBox only accepts "aggressive" as mode in phase 1 - does not load vpn config when I change this to "main"

To get vpnc running on Android device connecting to FRITZBox as vpn server the value in vpnc "nat-t-ike-02" (cd60464335df21f87cfdb2fc68b6a448 in binary) had to be changed to "nat-t-ike-03" (binary: 7d9419a65310ca6f2c179d9215529d56) by patching the vpnc binary

Hope this helps to help me (and all N9 FRITZBox users that need VPN)

Thanks again