diff --git a/srsepc/epc.conf.example b/srsepc/epc.conf.example
index 65f51981a..bce4085ac 100644
--- a/srsepc/epc.conf.example
+++ b/srsepc/epc.conf.example
@@ -48,21 +48,21 @@ sgi_if_addr=172.16.0.1
 #
 # Log levels can be set for individual layers. "all_level" sets log
 # level for all layers unless otherwise configured.
-# Format: e.g. phy_level = info
+# Format: e.g. s1ap_level = info
 #
 # In the same way, packet hex dumps can be limited for each level.
 # "all_hex_limit" sets the hex limit for all layers unless otherwise
 # configured.
-# Format: e.g. phy_hex_limit = 32
+# Format: e.g. s1ap_hex_limit = 32
 #
-# Logging layers: phy, mac, rlc, pdcp, rrc, nas, gtpu, usim, all
+# Logging layers: s1ap, gtpc, spgw, hss, all
 # Logging levels: debug, info, warning, error, none
 #
 # filename: File path to use for log output. Can be set to stdout
 #           to print logs to standard output
 #####################################################################
 [log]
-all_level = info
+all_level = debug
 all_hex_limit = 32
 filename = /tmp/epc.log
 
diff --git a/srsepc/hdr/mme/s1ap.h b/srsepc/hdr/mme/s1ap.h
index 509a887ee..fc4dd3d49 100644
--- a/srsepc/hdr/mme/s1ap.h
+++ b/srsepc/hdr/mme/s1ap.h
@@ -83,7 +83,7 @@ public:
   void add_new_ue_ctx(const ue_ctx_t &ue_ctx);
   bool delete_ue_ctx(ue_ctx_t *ue_ctx);
 
-  uint32_t allocate_m_tmsi();
+  uint32_t allocate_m_tmsi(uint32_t mme_ue_s1ap_id);
 
   s1ap_args_t                    m_s1ap_args;
   srslte::log_filter            *m_s1ap_log;
diff --git a/srsepc/src/mme/s1ap.cc b/srsepc/src/mme/s1ap.cc
index 03eaadd35..b9e303674 100644
--- a/srsepc/src/mme/s1ap.cc
+++ b/srsepc/src/mme/s1ap.cc
@@ -433,9 +433,11 @@ s1ap::activate_eps_bearer(uint32_t mme_s1ap_id, uint8_t ebi)
 }
 
 uint32_t
-s1ap::allocate_m_tmsi()
+s1ap::allocate_m_tmsi(uint32_t mme_ue_s1ap_id)
 {
-  return m_next_m_tmsi++;
+  uint32_t m_tmsi = m_next_m_tmsi++;
+  m_tmsi_to_s1ap_id.insert(std::pair<uint32_t,uint32_t>(m_tmsi,mme_ue_s1ap_id));
+  return m_tmsi;
 }
 
 void
diff --git a/srsepc/src/mme/s1ap_ctx_mngmt_proc.cc b/srsepc/src/mme/s1ap_ctx_mngmt_proc.cc
index 48efaee9f..70d3e7380 100644
--- a/srsepc/src/mme/s1ap_ctx_mngmt_proc.cc
+++ b/srsepc/src/mme/s1ap_ctx_mngmt_proc.cc
@@ -280,7 +280,7 @@ s1ap_ctx_mngmt_proc::handle_ue_context_release_request(LIBLTE_S1AP_MESSAGE_UECON
     if(ue_ctx->erabs_ctx[i].state != ERAB_DEACTIVATED)
     {
       active = true;
-      break;
+      ue_ctx->erabs_ctx[i].state = ERAB_DEACTIVATED;
     }
   }
   if(active == true)
@@ -288,10 +288,10 @@ s1ap_ctx_mngmt_proc::handle_ue_context_release_request(LIBLTE_S1AP_MESSAGE_UECON
     //There are active E-RABs, send delete session request
     m_mme_gtpc->send_delete_session_request(ue_ctx);
   }
-  m_s1ap->delete_ue_ctx(ue_ctx);
+  //m_s1ap->delete_ue_ctx(ue_ctx);
 
   //Delete UE context
-  m_s1ap_log->info("Deleted UE Context.\n");
+  m_s1ap_log->info("Deleted UE S1-U Context.\n");
   return true;
 }
 
diff --git a/srsepc/src/mme/s1ap_nas_transport.cc b/srsepc/src/mme/s1ap_nas_transport.cc
index 6746b7e00..990ee83d0 100644
--- a/srsepc/src/mme/s1ap_nas_transport.cc
+++ b/srsepc/src/mme/s1ap_nas_transport.cc
@@ -106,7 +106,7 @@ s1ap_nas_transport::handle_initial_ue_message(LIBLTE_S1AP_MESSAGE_INITIALUEMESSA
     return false;
   }
 
-  //Get Mobile ID
+
   if(attach_req.eps_mobile_id.type_of_id == LIBLTE_MME_EPS_MOBILE_ID_TYPE_IMSI)
   {
     //IMSI style attach
@@ -114,20 +114,27 @@ s1ap_nas_transport::handle_initial_ue_message(LIBLTE_S1AP_MESSAGE_INITIALUEMESSA
     for(int i=0;i<=14;i++){
       imsi  += attach_req.eps_mobile_id.imsi[i]*std::pow(10,14-i);
     }
+
   }
   else if(attach_req.eps_mobile_id.type_of_id == LIBLTE_MME_EPS_MOBILE_ID_TYPE_GUTI)
   {
     //GUTI style attach
+    m_s1ap_log->console("Received GUTI-style attach request\n");
     uint32_t m_tmsi = attach_req.eps_mobile_id.guti.m_tmsi;
     std::map<uint32_t,uint32_t>::iterator it = m_s1ap->m_tmsi_to_s1ap_id.find(m_tmsi);
     if(it == m_s1ap->m_tmsi_to_s1ap_id.end())
     {
       //FIXME Send Id request
-      m_s1ap_log->info("Could not find M-TMSI in attach request\n");
+      m_s1ap_log->console("Could not find M-TMSI in attach request\n");
       return false;
     }
+    m_s1ap_log->console("Found M-TMSI: %d\n",m_tmsi);
     ue_ctx_t *tmp = m_s1ap->find_ue_ctx(it->second);
-    imsi = tmp->imsi;
+    if(tmp!=NULL)
+    {
+      m_s1ap_log->console("Found UE context. IMSI: %015lu\n",tmp->imsi);
+      imsi = tmp->imsi;
+    }
   }
   m_s1ap_log->console("Attach request from IMSI: %015lu\n", imsi);
   m_s1ap_log->info("Attach request from IMSI: %015lu\n", imsi);
@@ -774,7 +781,8 @@ s1ap_nas_transport::pack_attach_accept(ue_ctx_t *ue_ctx, LIBLTE_S1AP_E_RABTOBESE
   attach_accept.guti.guti.mnc = m_s1ap->m_s1ap_args.mnc;
   attach_accept.guti.guti.mme_group_id = 0x0001;
   attach_accept.guti.guti.mme_code = 0x1a;
-  attach_accept.guti.guti.m_tmsi = m_s1ap->allocate_m_tmsi();
+  attach_accept.guti.guti.m_tmsi = m_s1ap->allocate_m_tmsi(ue_ctx->mme_ue_s1ap_id);
+
   /*
   typedef struct{
     uint32 m_tmsi;