Index: res/res_pjsip_pubsub.c
===================================================================
--- res/res_pjsip_pubsub.c	(revision 410558)
+++ res/res_pjsip_pubsub.c	(working copy)
@@ -762,7 +762,8 @@
 
 	expires_header = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_EXPIRES, rdata->msg_info.msg->hdr.next);
 
-	if (expires_header && expires_header->ivalue < endpoint->subscription.minexpiry) {
+	if (expires_header && (expires_header->ivalue == 0 ||
+			expires_header->ivalue < endpoint->subscription.minexpiry)) {
 		ast_log(LOG_WARNING, "Subscription expiration %d is too brief for endpoint %s. Minimum is %d\n",
 				expires_header->ivalue, ast_sorcery_object_get_id(endpoint), endpoint->subscription.minexpiry);
 		pjsip_endpt_respond_stateless(ast_sip_get_pjsip_endpoint(), rdata, 423, NULL, NULL, NULL);