Symptom:
Assertion failure at sess/sgsn/sgsn-app/s4_dp/s4_sn_dp_network.c:1340
  Note: Rcvd Invalid Event NTWK-INTRA-SGSN-HANDOFF-REQUEST from SM-APP in NTWK-INTRA-SGSN-RAU-BEGIN state for IMSI:404108570001380, NSAPI:5
  Function: s4_sn_dp_network_process_invalid_evt()
  Expression: 0
  Code: CRASH
  Proclet: sessmgr (f=87000,i=79)
  Process: card=4 cpu=1 arch=X pid=9063 cpu=~5% argv0=sessmgr
  Crash time: 2014-Aug-11+17:58:09 UTC
  Recent errno: 11 Resource temporarily unavailable
  Stack (30664@0xffff6000):
    [/X] __kernel_vsyscall() sp=0xffff60d8
    [/X] sn_assert() sp=0xffff6118
    [/X] s4_sn_dp_network_process_invalid_evt() sp=0xffff6868
    [/X] s4_sn_dp_network_handle_peer_request() sp=0xffff68a8
    [/X] s4_gprs_sm_s4_dp_intra_sgsn_ho_ind() sp=0xffff6958
    [/X] sgsn_inter_rat_suspend_s4_dp_in_2g() sp=0xffff69e8
    [/X] sessmgr_gprs_fsm_state_standby() sp=0xffff6c58
    [/X] sessmgr_gprs_fsm() sp=0xffff7428
    [/X] sgsn_send_irat_event_from_3g_to_2g() sp=0xffff7698
    [/X] pmm_ms_fsm_handle_new_con_in_detached() sp=0xffff77a8
    [/X] pmm_fsm_feed_event() sp=0xffff7838
    [/X] handle_new_con_with_peer_sgsn_ptmsi() sp=0xffff7d58
    [/X] acc_gmm_new_con_ind() sp=0xffff82b8
    [/X] access_iu_process_update_request_in_initial_ue() sp=0xffff8558
    [/X] SNUiRptConInd() sp=0xffff8a48
    [/X] RaUiRptConInd() sp=0xffff8a88
    [/X] raLiCnInitUEMsg() sp=0xffff8be8
    [/X] RaLiSptConInd() sp=0xffff8e68
    [/X] SpUiSptConInd() sp=0xffff8e88
    [/X] spConRequest() sp=0xffff9038
    [/X] spLiHndlCr() sp=0xffff96f8
    [/X] SpLiSntUDatInd() sp=0xffff98f8
    [/X] cmUnpkSntUDatInd() sp=0xffff9968
    [/X] spActvTsk() sp=0xffff99a8

Conditions:
Scenario from FSM trace:
---------------------------------------

LORC feature enabled
1) Attach and activate PDP in 2G
2) Ready to standby: Release Access Bearer Request/Response
3) Uplink Pdu received, MBR initiated
4) IRAT from 3G request
5) MBR Response failure from SGW {MBR is not aborted in step 4}
6) Deactivation started due to MBR failure
7) IRAT cancel from 3G
8) Again IRAT Request from 3G