diff --git a/skeletons/der_encoder.h b/skeletons/der_encoder.h
index 2acccaa..5a29613 100644
--- a/skeletons/der_encoder.h
+++ b/skeletons/der_encoder.h
@@ -42,6 +42,7 @@
 		struct asn1_TYPE_descriptor_s *type_descriptor,
 		size_t struct_length,
 		int tag_mode,		/* {-1,0,1}: IMPLICIT, no, EXPLICIT */
+		int last_tag_form,	/* {0,!0}: prim, constructed */
 		ber_tlv_tag_t tag,
 		asn_app_consume_bytes_f *consume_bytes_cb,
 		void *app_key