diff --git a/include/proto/stick_table.h b/include/proto/stick_table.h
index 7381737..7cfeaae 100644
--- a/include/proto/stick_table.h
+++ b/include/proto/stick_table.h
@@ -53,6 +53,8 @@
  * not NULL. Returns PE_NONE (0) if OK or an error code among :
  *   - PE_ENUM_OOR if <type> does not exist
  *   - PE_EXIST if <type> is already registered
+ *   - PE_ARG_NOT_USE if <sa> was provided but not expected
+ *   - PE_ARG_MISSING if <sa> was expected but not provided
  */
 static inline int stktable_alloc_data_type(struct stktable *t, int type, const char *sa)
 {
@@ -63,12 +65,27 @@
 		/* already allocated */
 		return PE_EXIST;
 
+	switch (stktable_data_types[type].arg_type) {
+	case ARG_T_NONE:
+		if (sa)
+			return PE_ARG_NOT_USED;
+		break;
+	case ARG_T_INT:
+		if (!sa)
+			return PE_ARG_MISSING;
+		t->data_arg[type].i = atoi(sa);
+		break;
+	case ARG_T_DELAY:
+		if (!sa)
+			return PE_ARG_MISSING;
+		sa = parse_time_err(sa, &t->data_arg[type].u, TIME_UNIT_MS);
+		if (sa)
+			return PE_ARG_INVC; /* invalid char */
+		break;
+	}
+
 	t->data_size      += stktable_data_types[type].data_length;
 	t->data_ofs[type]  = -t->data_size;
-	/* right now only int type is supported, but we may later support type-
-	 * specific arg type.
-	 */
-	t->data_arg[type].i = sa ? atoi(sa) : 0;
 	return PE_NONE;
 }