diff --git a/include/types/proto_http.h b/include/types/proto_http.h
index eebafc5d2..5ee2e0fd4 100644
--- a/include/types/proto_http.h
+++ b/include/types/proto_http.h
@@ -41,6 +41,8 @@
 #define TX_CK_INVALID	0x00000020	/* this session had a cookie which matches no server */
 #define TX_CK_DOWN	0x00000040	/* this session had cookie matching a down server */
 #define TX_CK_VALID	0x00000060	/* this session had cookie matching a valid server */
+#define TX_CK_EXPIRED	0x00000080	/* this session had an expired cookie (idle for too long) */
+#define TX_CK_OLD	0x000000A0	/* this session had too old a cookie (offered too long ago) */
 #define TX_CK_MASK	0x000000E0	/* mask to get this session's cookie flags */
 #define TX_CK_SHIFT	5		/* bit shift */
 
diff --git a/src/proto_http.c b/src/proto_http.c
index bf81196a8..71f5af599 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -837,7 +837,7 @@ void http_return_srv_error(struct session *s, struct stream_interface *si)
 extern const char sess_term_cond[8];
 extern const char sess_fin_state[8];
 extern const char *monthname[12];
-const char sess_cookie[4]     = "NIDV";		/* No cookie, Invalid cookie, cookie for a Down server, Valid cookie */
+const char sess_cookie[8]     = "NIDVEO67";	/* No cookie, Invalid cookie, cookie for a Down server, Valid cookie, Expired cookie, Old cookie */
 const char sess_set_cookie[8] = "N1I3PD5R";	/* No set-cookie, unknown, Set-Cookie Inserted, unknown,
 					    	   Set-cookie seen and left unchanged (passive), Set-cookie Deleted,
 						   unknown, Set-cookie Rewritten */