Android VPN with IPSec/XAuth

Hi everyone I' m trying to establish a VPN-Connection between an android-tablet (Android 4.0.3) with our Fortigate (MR3Patch8). I know the cookbook-article about how to establish a connection using L2TP over IPSec... but that' s not what i want. Since it is possible to use IPSec with Xauth since Android 4, i want to use this. We' re already using it with iPhones/iPads. And some blog-articles state that it' s also possible with android... but i cant get it to work. Actually i see just one single " negotiate progress IPsec phase 1" message with status success, that' s all. Not a proposal mismatch or error. And after a short time, i get a timeout on the tablet and see a delete_phase1_sa in the eventlog. My configuration looks like this atm Phase1

  config vpn ipsec phase1-interface      edit " v_test_android"           set type dynamic          set interface " cc_inet"           set dhgrp 2          set peertype one          set xauthtype auto          set mode aggressive          set mode-cfg enable          set proposal aes128-sha1          set peerid " androidvpn"           set authusrgrp " androidvpn"           set ipv4-start-ip 192.168.244.30          set ipv4-end-ip 192.168.244.40          set ipv4-netmask 255.255.255.0          set dns-mode auto          set psksecret ***      next  end  

Phase2

config vpn ipsec phase2-interface      edit " v_test_android_ph2"           set phase1name " v_test_android"           set proposal aes128-sha1      next  end

On the tablet i' ve configured a " IPSec Xauth PSK" connection, using the " androidvpn" as IPsec-ID. I' ve already tried many combinations with different proposals, with or without peertype, with PAP or CHAP instead of auto... nothing worked. I' m sure it' s no matter of user/password or PSK, because on an iPad i can connect with this proposals. Does anyone already made this to work or has some hints for me? Thx a lot Mike