diff --git a/lib/core/include/core_tlv_msg.h b/lib/core/include/core_tlv_msg.h
index 314e0aae5..821cd85b7 100644
--- a/lib/core/include/core_tlv_msg.h
+++ b/lib/core/include/core_tlv_msg.h
@@ -66,6 +66,7 @@ typedef struct _tlv_desc_t {
     tlv_type_e ctype;
     c_uint16_t type;
     c_uint16_t length;
+    c_uint8_t  instance;
     c_uint16_t vsize;
     void *child_descs[];
 } tlv_desc_t;
diff --git a/lib/core/src/tlv_msg.c b/lib/core/src/tlv_msg.c
index d891b2b73..1017eaf31 100644
--- a/lib/core/src/tlv_msg.c
+++ b/lib/core/src/tlv_msg.c
@@ -5,7 +5,7 @@
 
 tlv_desc_t tlv_desc_more = 
 {
-    TLV_MORE, 0, TLV_MORE, 0, { NULL }
+    TLV_MORE, 0, TLV_MAX_MORE, 0, 0, { NULL }
 };
 
 static tlv_t* _tlv_add_leaf(
@@ -21,9 +21,11 @@ static tlv_t* _tlv_add_leaf(
             d_trace(1, "V_1B:%02x", v->v);
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, 1, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, 1, desc->instance, (c_uint8_t*)&v->v);
             else
-                tlv = tlv_add(tlv, desc->type, 1, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_add(tlv, 
+                        desc->type, 1, desc->instance, (c_uint8_t*)&v->v);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -36,9 +38,11 @@ static tlv_t* _tlv_add_leaf(
             v->v = htons(v->v);
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, 2, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, 2, desc->instance, (c_uint8_t*)&v->v);
             else
-                tlv = tlv_add(tlv, desc->type, 2, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_add(tlv, 
+                        desc->type, 2, desc->instance, (c_uint8_t*)&v->v);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -53,9 +57,11 @@ static tlv_t* _tlv_add_leaf(
             v->v = htonl(v->v);
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, 3, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, 3, desc->instance, (c_uint8_t*)&v->v);
             else
-                tlv = tlv_add(tlv, desc->type, 3, 0, (c_uint8_t*)&v->v);
+                tlv = tlv_add(tlv, 
+                        desc->type, 3, desc->instance, (c_uint8_t*)&v->v);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -83,9 +89,11 @@ static tlv_t* _tlv_add_leaf(
             d_trace_hex(1, v->v, v->l);
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, desc->length, 0, v->v);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, desc->length, desc->instance, v->v);
             else
-                tlv = tlv_add(tlv, desc->type, desc->length, 0, v->v);
+                tlv = tlv_add(tlv, 
+                        desc->type, desc->length, desc->instance, v->v);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -99,9 +107,11 @@ static tlv_t* _tlv_add_leaf(
             d_trace_hex(1, v->v, v->l);
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, v->l, 0, v->v);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, v->l, desc->instance, v->v);
             else
-                tlv = tlv_add(tlv, desc->type, v->l, 0, v->v);
+                tlv = tlv_add(tlv, 
+                        desc->type, v->l, desc->instance, v->v);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -110,9 +120,11 @@ static tlv_t* _tlv_add_leaf(
             d_trace(1, "V_NULL" );
 
             if (parent_tlv)
-                tlv = tlv_embed(parent_tlv, desc->type, 0, 0, NULL);
+                tlv = tlv_embed(parent_tlv, 
+                        desc->type, 0, desc->instance, NULL);
             else
-                tlv = tlv_add(tlv, desc->type, 0, 0, NULL);
+                tlv = tlv_add(tlv, 
+                        desc->type, 0, desc->instance, NULL);
             d_assert(tlv, return NULL, "Can't add TLV");
             break;
         }
@@ -162,13 +174,15 @@ static c_uint32_t _tlv_add_compound(tlv_t **root, tlv_t *parent_tlv,
 
                 if (desc->ctype == TLV_COMPOUND)
                 {
-                    d_trace(1, "\nBUILD %sC#%d T:%d (vsz=%d) off:%p ",
-                            indent, i, desc->type, desc->vsize, p + offset);
+                    d_trace(1, "\nBUILD %sC#%d T:%d I:%d (vsz=%d) off:%p ",
+                            indent, i, desc->type, desc->instance, desc->vsize,
+                            p + offset);
 
                     if (parent_tlv)
-                        tlv = tlv_embed(parent_tlv, desc->type, 0, 0, NULL);
+                        tlv = tlv_embed(parent_tlv, 
+                                desc->type, 0, desc->instance, NULL);
                     else
-                        tlv = tlv_add(tlv, desc->type, 0, 0, NULL);
+                        tlv = tlv_add(tlv, desc->type, 0, desc->instance, NULL);
 
                     r = _tlv_add_compound(&emb_tlv, tlv, desc,
                             p + offset + sizeof(tlv_header_t), depth + 1);
@@ -178,8 +192,9 @@ static c_uint32_t _tlv_add_compound(tlv_t **root, tlv_t *parent_tlv,
                 }
                 else
                 {
-                    d_trace(1, "\nBUILD %sL#%d T:%d L:%d (cls:%d vsz:%d) off:%p ",
-                            indent, i, desc->type, desc->length,
+                    d_trace(1, "\nBUILD %sL#%d T:%d L:%d I:%d "
+                            "(cls:%d vsz:%d) off:%p ",
+                            indent, i, desc->type, desc->length, desc->instance,
                             desc->ctype, desc->vsize, p + offset);
 
                     tlv = _tlv_add_leaf(parent_tlv, tlv, desc, p + offset);
@@ -203,13 +218,15 @@ static c_uint32_t _tlv_add_compound(tlv_t **root, tlv_t *parent_tlv,
             {
                 if (desc->ctype == TLV_COMPOUND)
                 {
-                    d_trace(1, "\nBUILD %sC#%d T:%d (vsz=%d) off:%p ",
-                            indent, i, desc->type, desc->vsize, p + offset);
+                    d_trace(1, "\nBUILD %sC#%d T:%d I:%d (vsz=%d) off:%p ",
+                            indent, i, desc->type, desc->instance, 
+                            desc->vsize, p + offset);
 
                     if (parent_tlv)
-                        tlv = tlv_embed(parent_tlv, desc->type, 0, 0, NULL);
+                        tlv = tlv_embed(parent_tlv, 
+                                desc->type, 0, desc->instance, NULL);
                     else
-                        tlv = tlv_add(tlv, desc->type, 0, 0, NULL);
+                        tlv = tlv_add(tlv, desc->type, 0, desc->instance, NULL);
 
                     r = _tlv_add_compound(&emb_tlv, tlv, desc,
                             p + offset + sizeof(tlv_header_t), depth + 1);
@@ -219,8 +236,9 @@ static c_uint32_t _tlv_add_compound(tlv_t **root, tlv_t *parent_tlv,
                 }
                 else
                 {
-                    d_trace(1, "\nBUILD %sL#%d T:%d L:%d (cls:%d vsz:%d) off:%p ",
-                            indent, i, desc->type, desc->length,
+                    d_trace(1, "\nBUILD %sL#%d T:%d L:%d I:%d "
+                            "(cls:%d vsz:%d) off:%p ",
+                            indent, i, desc->type, desc->length, desc->instance,
                             desc->ctype, desc->vsize, p + offset);
 
                     tlv = _tlv_add_leaf(parent_tlv, tlv, desc, p + offset);
@@ -287,7 +305,7 @@ static tlv_desc_t* _tlv_find_desc(c_uint8_t *desc_index,
     {
         d_trace(5, "%d, ", desc->type);
 
-        if (desc->type == tlv->type)
+        if (desc->type == tlv->type && desc->instance == tlv->instance)
         {
             *desc_index = i;
             *tlv_offset = offset;
@@ -491,8 +509,9 @@ static status_t _tlv_parse_compound(void *msg, tlv_desc_t *parent_desc,
                 return CORE_ERROR;
             }
 
-            d_trace(1, "\nPARSE %sC#%d T:%d (vsz=%d) off:%p ",
-                    indent, i++, desc->type, desc->vsize, p + offset);
+            d_trace(1, "\nPARSE %sC#%d T:%d I:%d (vsz=%d) off:%p ",
+                    indent, i++, desc->type, desc->instance, 
+                    desc->vsize, p + offset);
 
             offset += sizeof(tlv_header_t);
 
@@ -508,8 +527,9 @@ static status_t _tlv_parse_compound(void *msg, tlv_desc_t *parent_desc,
         }
         else
         {
-            d_trace(1, "\nPARSE %sL#%d T:%d L:%d (cls:%d vsz:%d) off:%p ",
-                    indent, i++, desc->type, desc->length,
+            d_trace(1, "\nPARSE %sL#%d T:%d L:%d I:%d "
+                    "(cls:%d vsz:%d) off:%p ",
+                    indent, i++, desc->type, desc->length, desc->instance,
                     desc->ctype, desc->vsize, p + offset);
 
             rv = _tlv_parse_leaf(p + offset, desc, tlv);
diff --git a/lib/gtp/gtpv2c_tlv.c b/lib/gtp/gtpv2c_tlv.c
index 73b8e4bdb..1c155f728 100644
--- a/lib/gtp/gtpv2c_tlv.c
+++ b/lib/gtp/gtpv2c_tlv.c
@@ -5,6 +5,7 @@ tlv_desc_t tlv_desc_authorization_policy_support =
     TLV_UINT8,
     TLV_AUTHORIZATION_POLICY_SUPPORT_TYPE,
     TLV_AUTHORIZATION_POLICY_SUPPORT_LEN,
+    0,
     sizeof(tlv_authorization_policy_support_t),
     { NULL }
 };
@@ -14,6 +15,7 @@ tlv_desc_t tlv_desc_ms_security_history =
     TLV_COMPOUND,
     TLV_MS_SECURITY_HISTORY_TYPE,
     TLV_MS_SECURITY_HISTORY_LEN,
+    0, 
     sizeof(tlv_ms_security_history_t),
     {
         &tlv_desc_authorization_policy_support,
@@ -26,6 +28,7 @@ tlv_desc_t tlv_desc_ms_info =
     TLV_COMPOUND,
     TLV_MS_INFO_TYPE,
     TLV_MS_INFO_LEN,
+    0, 
     sizeof(tlv_ms_info_t),
     {
         &tlv_desc_ms_security_history,
@@ -38,6 +41,7 @@ tlv_desc_t tlv_desc_bs_id =
     TLV_VAR_STR,
     TLV_BS_ID_TYPE,
     TLV_BS_ID_LEN,
+    0, 
     sizeof(tlv_bs_id_t),
     { NULL }
 };
@@ -47,6 +51,7 @@ tlv_desc_t tlv_desc_bs_info =
     TLV_COMPOUND,
     TLV_BS_INFO_TYPE,
     TLV_BS_INFO_LEN,
+    0, 
     sizeof(tlv_bs_info_t),
     {
         &tlv_desc_bs_id,
@@ -55,7 +60,7 @@ tlv_desc_t tlv_desc_bs_info =
 };
 
 tlv_desc_t tlv_desc_msg_ms_preattachment_req = {
-    TLV_MESSAGE, 0, 0, 0, {
+    TLV_MESSAGE, 0, 0, 0, 0, {
     &tlv_desc_ms_info,
     &tlv_desc_bs_info,
     NULL,
diff --git a/test/gtp_message_test.c b/test/gtp_message_test.c
index c331b2dd9..e56d3cc56 100644
--- a/test/gtp_message_test.c
+++ b/test/gtp_message_test.c
@@ -11,14 +11,14 @@ static void gtp_message_test1(abts_case *tc, void *data)
     tlv_msg_ms_preattachment_req reqv2;
 
     pkbuf_t *req = NULL;
-#if 0
+#if 1
     c_uint8_t *buf;
     c_uint32_t buflen;
 #endif
 
     {
         extern int _tlv_msg;
-        _tlv_msg = 0;
+        _tlv_msg = 1;
     }
     /* Initialize message value structure */
     memset(&reqv, 0, sizeof(tlv_msg_ms_preattachment_req));
@@ -35,7 +35,7 @@ static void gtp_message_test1(abts_case *tc, void *data)
     tlv_build_msg(&req, &tlv_desc_msg_ms_preattachment_req, &reqv,
             TLV_MODE_T1_L2_I1);
 
-#if 0
+#if 1
     d_print_hex(req->payload, req->len);
 #endif
 
@@ -49,13 +49,13 @@ static void gtp_message_test1(abts_case *tc, void *data)
     if (COMPD_ISSET(reqv2.ms_info))
         if (COMPD_ISSET(reqv2.ms_info.ms_security_history))
             if (VALUE_ISSET(reqv2.ms_info.ms_security_history.authorization_policy_support))
-#if 0
+#if 1
                 d_print("%02x", VALUE_GET(reqv2.ms_info.ms_security_history.authorization_policy_support));
 #else
     ;
 #endif
 
-#if 0
+#if 1
     if (COMPD_ISSET(reqv2.bs_info))
         if (OCTET_ISSET(reqv2.bs_info.bs_id))
         {