diff --git a/lib/dns/include/dns/compress.h b/lib/dns/include/dns/compress.h
index 80907d306b..2aad77eb6d 100644
--- a/lib/dns/include/dns/compress.h
+++ b/lib/dns/include/dns/compress.h
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: compress.h,v 1.23 2001/01/04 19:25:59 bwelling Exp $ */
+/* $Id: compress.h,v 1.24 2001/01/06 00:35:30 bwelling Exp $ */
 
 #ifndef DNS_COMPRESS_H
 #define DNS_COMPRESS_H 1
@@ -160,13 +160,17 @@ void
 dns_compress_add(dns_compress_t *cctx, dns_name_t *name, dns_name_t *prefix,
 		 isc_uint16_t offset);
 /*
- *	Add compression pointers for name to the compression table,
+ *	Add compression pointers for 'name' to the compression table,
  *	not replacing existing pointers.
  *
  *	Requires:
  *		'cctx' initialized
+ *
  *		'name' must be initialized and absolute, and must remain
  *		valid until the message compression is complete.
+ *
+ *		'prefix' must be a prefix returned by
+ *		dns_compress_findglobal().
  */
 
 void