diff --git a/src/mme/emm_sm.c b/src/mme/emm_sm.c
index b5f33998b9..1e94ec43fe 100644
--- a/src/mme/emm_sm.c
+++ b/src/mme/emm_sm.c
@@ -13,8 +13,8 @@
 #include "emm_handler.h"
 #include "emm_build.h"
 #include "esm_handler.h"
-#include "mme_s11_handler.h"
 #include "nas_path.h"
+#include "mme_gtp_path.h"
 
 static void emm_state_attach_request(fsm_t *s, event_t *e,
         mme_ue_t *mme_ue, nas_message_t *message);
@@ -82,6 +82,7 @@ void emm_state_detached(fsm_t *s, event_t *e)
 
 void emm_state_identity(fsm_t *s, event_t *e)
 {
+    status_t rv;
     mme_ue_t *mme_ue = NULL;
 
     d_assert(s, return, "Null param");
@@ -96,7 +97,6 @@ void emm_state_identity(fsm_t *s, event_t *e)
     {
         case FSM_ENTRY_SIG:
         {
-            status_t rv;
             pkbuf_t *emmbuf = NULL;
 
             rv = emm_build_identity_request(&emmbuf, mme_ue);
@@ -139,7 +139,9 @@ void emm_state_identity(fsm_t *s, event_t *e)
                     {
                         if (MME_HAVE_SGW_S11_PATH(mme_ue))
                         {
-                            mme_s11_handle_delete_all_sessions_in_ue(mme_ue);
+                            rv = mme_gtp_send_delete_all_sessions(mme_ue);
+                            d_assert(rv == CORE_OK, break,
+                                "mme_gtp_send_delete_all_sessions failed");
                         }
                         else
                         {
@@ -431,7 +433,10 @@ void emm_state_attached(fsm_t *s, event_t *e)
     
                     if (MME_HAVE_SGW_S11_PATH(mme_ue))
                     {
-                        mme_s11_handle_delete_all_sessions_in_ue(mme_ue);
+                        status_t rv;
+                        rv = mme_gtp_send_delete_all_sessions(mme_ue);
+                        d_assert(rv == CORE_OK, break,
+                            "mme_gtp_send_delete_all_sessions failed");
                     }
                     else
                     {
@@ -526,6 +531,8 @@ void emm_state_exception(fsm_t *s, event_t *e)
 static void emm_state_attach_request(fsm_t *s, event_t *e,
         mme_ue_t *mme_ue, nas_message_t *message)
 {
+    status_t rv;
+
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
     d_assert(mme_ue, return, "Null param");
@@ -550,7 +557,6 @@ static void emm_state_attach_request(fsm_t *s, event_t *e,
     {
         if (SECURITY_CONTEXT_IS_VALID(mme_ue))
         {
-            status_t rv;
             rv = nas_send_emm_to_esm(mme_ue, &mme_ue->pdn_connectivity_request);
             d_assert(rv == CORE_OK,, "nas_send_emm_to_esm failed");
             FSM_TRAN(s, &emm_state_default_esm);
@@ -559,7 +565,9 @@ static void emm_state_attach_request(fsm_t *s, event_t *e,
         {
             if (MME_HAVE_SGW_S11_PATH(mme_ue))
             {
-                mme_s11_handle_delete_all_sessions_in_ue(mme_ue);
+                rv = mme_gtp_send_delete_all_sessions(mme_ue);
+                d_assert(rv == CORE_OK, return,
+                    "mme_gtp_send_delete_all_sessions failed");
             }
             else
             {
diff --git a/src/mme/mme_gtp_path.c b/src/mme/mme_gtp_path.c
index a53469d52e..1ee1b7a264 100644
--- a/src/mme/mme_gtp_path.c
+++ b/src/mme/mme_gtp_path.c
@@ -154,6 +154,34 @@ status_t mme_gtp_send_delete_session_request(mme_sess_t *sess)
     return CORE_OK;
 }
 
+status_t mme_gtp_send_delete_all_sessions(mme_ue_t *mme_ue)
+{
+    status_t rv;
+    mme_sess_t *sess = NULL, *next_sess = NULL;
+
+    d_assert(mme_ue, return CORE_ERROR, "Null param");
+    sess = mme_sess_first(mme_ue);
+    while (sess != NULL)
+    {
+        next_sess = mme_sess_next(sess);
+
+        if (MME_HAVE_SGW_S1U_PATH(sess))
+        {
+            rv = mme_gtp_send_delete_session_request(sess);
+            d_assert(rv == CORE_OK, return CORE_ERROR,
+                    "mme_gtp_send_delete_session_request error");
+        }
+        else
+        {
+            mme_sess_remove(sess);
+        }
+
+        sess = next_sess;
+    }
+
+    return CORE_OK;
+}
+
 status_t mme_gtp_send_create_bearer_response(mme_bearer_t *bearer)
 {
     status_t rv;
diff --git a/src/mme/mme_gtp_path.h b/src/mme/mme_gtp_path.h
index b86a742189..ac6346a988 100644
--- a/src/mme/mme_gtp_path.h
+++ b/src/mme/mme_gtp_path.h
@@ -16,6 +16,8 @@ CORE_DECLARE(status_t) mme_gtp_send_modify_bearer_request(
         mme_bearer_t *bearer);
 CORE_DECLARE(status_t) mme_gtp_send_delete_session_request(
         mme_sess_t *sess);
+CORE_DECLARE(status_t) mme_gtp_send_delete_all_sessions(
+        mme_ue_t *mme_ue);
 CORE_DECLARE(status_t) mme_gtp_send_create_bearer_response(
         mme_bearer_t *bearer);
 CORE_DECLARE(status_t) mme_gtp_send_release_access_bearers_response(
diff --git a/src/mme/mme_s11_handler.c b/src/mme/mme_s11_handler.c
index 4a3f71c9c1..582f00a73a 100644
--- a/src/mme/mme_s11_handler.c
+++ b/src/mme/mme_s11_handler.c
@@ -124,59 +124,6 @@ void mme_s11_handle_modify_bearer_response(
     d_assert(rv == CORE_OK, return, "xact_commit error");
 }
 
-void mme_s11_handle_delete_all_sessions_in_ue(mme_ue_t *mme_ue)
-{
-    status_t rv;
-    mme_sess_t *sess = NULL, *next_sess = NULL;
-
-    d_assert(mme_ue, return, "Null param");
-    sess = mme_sess_first(mme_ue);
-    while (sess != NULL)
-    {
-        next_sess = mme_sess_next(sess);
-
-        if (MME_HAVE_SGW_S1U_PATH(sess))
-        {
-            rv = mme_gtp_send_delete_session_request(sess);
-            d_assert(rv == CORE_OK, return,
-                    "mme_gtp_send_delete_session_request error");
-        }
-        else
-        {
-            mme_sess_remove(sess);
-        }
-
-        sess = next_sess;
-    }
-}
-
-void mme_s11_handle_delete_session_response(
-        gtp_xact_t *xact, mme_ue_t *mme_ue, gtp_delete_session_response_t *rsp)
-{
-    status_t rv;
-    mme_sess_t *sess = NULL;
-
-    d_assert(xact, return, "Null param");
-    d_assert(mme_ue, return, "Null param");
-    d_assert(rsp, return, "Null param");
-    sess = GTP_XACT_RETRIEVE_SESSION(xact);
-    d_assert(sess, return, "Null param");
-
-    if (rsp->cause.presence == 0)
-    {
-        d_error("No Cause");
-        return;
-    }
-
-    d_trace(3, "[GTP] Delete Session Response : "
-            "MME[%d] <-- SGW[%d]\n", mme_ue->mme_s11_teid, mme_ue->sgw_s11_teid);
-
-    mme_sess_remove(sess);
-
-    rv = gtp_xact_commit(xact);
-    d_assert(rv == CORE_OK, return, "xact_commit error");
-}
-
 void mme_s11_handle_create_bearer_request(
         gtp_xact_t *xact, mme_ue_t *mme_ue, gtp_create_bearer_request_t *req)
 {
diff --git a/src/mme/mme_s11_handler.h b/src/mme/mme_s11_handler.h
index 2533f6f8fc..831e7cc6fa 100644
--- a/src/mme/mme_s11_handler.h
+++ b/src/mme/mme_s11_handler.h
@@ -15,7 +15,6 @@ CORE_DECLARE(void) mme_s11_handle_create_session_response(
         gtp_create_session_response_t *rsp);
 CORE_DECLARE(void) mme_s11_handle_modify_bearer_response(
         gtp_xact_t *xact, mme_ue_t *mme_ue, gtp_modify_bearer_response_t *rsp);
-CORE_DECLARE(void) mme_s11_handle_delete_all_sessions_in_ue(mme_ue_t *mme_ue);
 CORE_DECLARE(void) mme_s11_handle_delete_session_response(
         gtp_xact_t *xact, mme_ue_t *mme_ue, gtp_delete_session_response_t *rsp);
 CORE_DECLARE(void) mme_s11_handle_create_bearer_request(
diff --git a/src/mme/s1ap_build.c b/src/mme/s1ap_build.c
index a6b4a7f803..1efed6e1c7 100644
--- a/src/mme/s1ap_build.c
+++ b/src/mme/s1ap_build.c
@@ -536,28 +536,7 @@ status_t s1ap_build_ue_context_release_commmand(
         ies->uE_S1AP_IDs.choice.mME_UE_S1AP_ID = enb_ue->mme_ue_s1ap_id;
     }
 
-    ies->cause.present = cause->present;
-    switch(ies->cause.present)
-    {
-        case S1ap_Cause_PR_radioNetwork:
-            ies->cause.choice.radioNetwork = cause->choice.radioNetwork;
-            break;
-        case S1ap_Cause_PR_transport:
-            ies->cause.choice.transport = cause->choice.transport;
-            break;
-        case S1ap_Cause_PR_nas:
-            ies->cause.choice.nas = cause->choice.nas;
-            break;
-        case S1ap_Cause_PR_protocol:
-            ies->cause.choice.protocol = cause->choice.protocol;
-            break;
-        case S1ap_Cause_PR_misc:
-            ies->cause.choice.misc = cause->choice.misc;
-            break;
-        default:
-            d_error("Invalid cause type : %d", ies->cause.present);
-            break;
-    }
+    s1ap_build_cause(&ies->cause, cause);
 
     message.procedureCode = S1ap_ProcedureCode_id_UEContextRelease;
     message.direction = S1AP_PDU_PR_initiatingMessage;