diff --git a/src/hlua.c b/src/hlua.c
index f9d1d69..21351cd 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -5346,6 +5346,9 @@
 	MAY_LJMP(check_args(L, 1, "req_get_headers"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_get_headers(L, htxn, &htxn->s->txn->req);
 }
 
@@ -5356,6 +5359,9 @@
 	MAY_LJMP(check_args(L, 1, "res_get_headers"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_get_headers(L, htxn, &htxn->s->txn->rsp);
 }
 
@@ -5393,6 +5399,9 @@
 	MAY_LJMP(check_args(L, 4, "req_rep_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	return MAY_LJMP(hlua_http_rep_hdr(L, htxn, &htxn->s->txn->req, ACT_HTTP_REPLACE_HDR));
 }
 
@@ -5403,6 +5412,9 @@
 	MAY_LJMP(check_args(L, 4, "res_rep_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	return MAY_LJMP(hlua_http_rep_hdr(L, htxn, &htxn->s->txn->rsp, ACT_HTTP_REPLACE_HDR));
 }
 
@@ -5413,6 +5425,9 @@
 	MAY_LJMP(check_args(L, 4, "req_rep_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	return MAY_LJMP(hlua_http_rep_hdr(L, htxn, &htxn->s->txn->req, ACT_HTTP_REPLACE_VAL));
 }
 
@@ -5423,6 +5438,9 @@
 	MAY_LJMP(check_args(L, 4, "res_rep_val"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	return MAY_LJMP(hlua_http_rep_hdr(L, htxn, &htxn->s->txn->rsp, ACT_HTTP_REPLACE_VAL));
 }
 
@@ -5462,6 +5480,9 @@
 	MAY_LJMP(check_args(L, 2, "req_del_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_del_hdr(L, htxn, &htxn->s->txn->req);
 }
 
@@ -5469,9 +5490,12 @@
 {
 	struct hlua_txn *htxn;
 
-	MAY_LJMP(check_args(L, 2, "req_del_hdr"));
+	MAY_LJMP(check_args(L, 2, "res_del_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_del_hdr(L, htxn, &htxn->s->txn->rsp);
 }
 
@@ -5523,6 +5547,9 @@
 	MAY_LJMP(check_args(L, 3, "req_add_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_add_hdr(L, htxn, &htxn->s->txn->req);
 }
 
@@ -5533,6 +5560,9 @@
 	MAY_LJMP(check_args(L, 3, "res_add_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	return hlua_http_add_hdr(L, htxn, &htxn->s->txn->rsp);
 }
 
@@ -5543,6 +5573,9 @@
 	MAY_LJMP(check_args(L, 3, "req_set_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	hlua_http_del_hdr(L, htxn, &htxn->s->txn->req);
 	return hlua_http_add_hdr(L, htxn, &htxn->s->txn->req);
 }
@@ -5554,6 +5587,9 @@
 	MAY_LJMP(check_args(L, 3, "res_set_hdr"));
 	htxn = MAY_LJMP(hlua_checkhttp(L, 1));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	hlua_http_del_hdr(L, htxn, &htxn->s->txn->rsp);
 	return hlua_http_add_hdr(L, htxn, &htxn->s->txn->rsp);
 }
@@ -5565,6 +5601,9 @@
 	size_t name_len;
 	const char *name = MAY_LJMP(luaL_checklstring(L, 2, &name_len));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	lua_pushboolean(L, http_replace_req_line(0, name, name_len, htxn->p, htxn->s) != -1);
 	return 1;
 }
@@ -5576,6 +5615,9 @@
 	size_t name_len;
 	const char *name = MAY_LJMP(luaL_checklstring(L, 2, &name_len));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	lua_pushboolean(L, http_replace_req_line(1, name, name_len, htxn->p, htxn->s) != -1);
 	return 1;
 }
@@ -5587,6 +5629,9 @@
 	size_t name_len;
 	const char *name = MAY_LJMP(luaL_checklstring(L, 2, &name_len));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	/* Check length. */
 	if (name_len > trash.size - 1) {
 		lua_pushboolean(L, 0);
@@ -5611,6 +5656,9 @@
 	size_t name_len;
 	const char *name = MAY_LJMP(luaL_checklstring(L, 2, &name_len));
 
+	if (htxn->dir != SMP_OPT_DIR_REQ)
+		WILL_LJMP(lua_error(L));
+
 	lua_pushboolean(L, http_replace_req_line(3, name, name_len, htxn->p, htxn->s) != -1);
 	return 1;
 }
@@ -5622,6 +5670,9 @@
 	unsigned int code = MAY_LJMP(luaL_checkinteger(L, 2));
 	const char *reason = MAY_LJMP(luaL_optlstring(L, 3, NULL, NULL));
 
+	if (htxn->dir != SMP_OPT_DIR_RES)
+		WILL_LJMP(lua_error(L));
+
 	http_set_status(code, reason, htxn->s);
 	return 0;
 }