diff --git a/skeletons/NULL.c b/skeletons/NULL.c
index 62bc91e..fb21c75 100644
--- a/skeletons/NULL.c
+++ b/skeletons/NULL.c
@@ -23,8 +23,13 @@
 	NULL_encode_der,	/* Special handling of DER encoding */
 	NULL_decode_xer,
 	NULL_encode_xer,
+#ifdef	ASN_DISABLE_PER_SUPPORT
+	0,
+	0,
+#else
 	NULL_decode_uper,	/* Unaligned PER decoder */
 	NULL_encode_uper,	/* Unaligned PER encoder */
+#endif	/* ASN_DISABLE_PER_SUPPORT */
 	0, /* Use generic outmost tag fetcher */
 	asn_DEF_NULL_tags,
 	sizeof(asn_DEF_NULL_tags) / sizeof(asn_DEF_NULL_tags[0]),