diff --git a/src/smblib/smbdefs.h b/src/smblib/smbdefs.h
index cc9926384557707cdd1a2c7cdb15d1d61a15915b..b3d1a135bcad22a14136f4f834d5232da98d4a9f 100644
--- a/src/smblib/smbdefs.h
+++ b/src/smblib/smbdefs.h
@@ -559,6 +559,9 @@ typedef struct _PACK {		/* Network (type and address) */
 
 } net_t;
 
+								/* Valid bits in smbmsg_t.flags					*/
+#define MSG_FLAG_HASHED	(1<<0)	/* Message has been hashed with smb_hashmsg()	*/
+
 typedef struct {				/* Message */
 
 	idxrec_t	idx;			/* Index */
@@ -598,6 +601,7 @@ typedef struct {				/* Message */
 	ulong		expiration; 	/* Message will expire on this day (if >0) */
 	ulong		priority;		/* Message priority (0 is lowest) */
 	ulong		cost;			/* Cost to download/read */
+	ulong		flags;			/* Various smblib run-time flags (see MSG_FLAG_*) */
 
 } smbmsg_t;