--- libss7-2.0.original/libss7.h	2014-06-09 23:48:47.000000000 +0400
+++ libss7-2.0/libss7.h	2016-03-21 16:01:15.921315257 +0300
@@ -316,6 +316,8 @@
 	/* Backward call indicator */
 	unsigned char called_party_status_ind;
 	unsigned char echocontrol_ind;
+	/* Optional backward call indicators */
+	unsigned char inband_available;
 } ss7_event_acm;
 
 typedef struct {