diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 1a7f04beed..8c58d20d82 100755
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -6823,6 +6823,11 @@ static void handle_response(struct sip_pvt *p, int resp, char *rest, struct sip_
 				p->alreadygone = 1;
 				if (!p->owner)
 					p->needdestroy = 1;
+			} else if ((resp >= 100) && (resp < 200)) {
+				/* Unknown 1xx repsonses should be treated as 100 */
+				if (!strcasecmp(msg, "INVITE")) {
+					sip_cancel_destroy(p);
+				}
 			} else
 				ast_log(LOG_NOTICE, "Dunno anything about a %d %s response from %s\n", resp, rest, p->owner ? p->owner->name : ast_inet_ntoa(iabuf, sizeof(iabuf), p->sa.sin_addr));
 		}