diff --git a/libs/openzap/src/ozmod/ozmod_zt/ozmod_zt.h b/libs/openzap/src/ozmod/ozmod_zt/ozmod_zt.h
index f82cf0ff10..687269a983 100644
--- a/libs/openzap/src/ozmod/ozmod_zt/ozmod_zt.h
+++ b/libs/openzap/src/ozmod/ozmod_zt/ozmod_zt.h
@@ -242,7 +242,7 @@ ZT_SIG_CLEAR				= (1 << 7),
 ZT_SIG_HDLCRAW				= ((1 << 8)  | ZT_SIG_CLEAR),
 ZT_SIG_HDLCFCS				= ((1 << 9)  | ZT_SIG_HDLCRAW),
 ZT_SIG_CAS                  = (1 << 15),
-ZT_SIG_HARDHDLC				= (1 << 19),
+ZT_SIG_HARDHDLC				= ((1 << 19) | ZT_SIG_CLEAR),
 } zt_sigtype_t;
 
 typedef enum {