Index: channels/chan_sip.c
===================================================================
--- channels/chan_sip.c	(revision 323141)
+++ channels/chan_sip.c	(working copy)
@@ -23955,7 +23955,7 @@
 		}
 
 		p->subscribed = MWI_NOTIFICATION;
-		if (ast_test_flag(&authpeer->flags[1], SIP_PAGE2_SUBSCRIBEMWIONLY)) {
+		if (!ast_test_flag(&authpeer->flags[1], SIP_PAGE2_SUBSCRIBEMWIONLY)) {
 			add_peer_mwi_subs(authpeer);
 		}
 		if (authpeer->mwipvt && authpeer->mwipvt != p) {	/* Destroy old PVT if this is a new one */
Index: main/event.c
===================================================================
--- main/event.c	(revision 323141)
+++ main/event.c	(working copy)
@@ -444,6 +444,7 @@
 	};
 	const enum ast_event_type event_types[] = { type, AST_EVENT_ALL };
 	int i;
+	int has_check = 0;
 
 	if (type >= AST_EVENT_TOTAL) {
 		ast_log(LOG_ERROR, "%u is an invalid type!\n", type);
@@ -493,6 +494,7 @@
 
 		if (insert) {
 			AST_LIST_INSERT_TAIL(&check_ie_vals.ie_vals, ie_value, entry);
+			has_check++;
 		} else {
 			ast_log(LOG_WARNING, "Unsupported PLTYPE(%d)\n", ie_value->ie_pltype);
 		}
@@ -503,7 +505,7 @@
 		AST_RWDLLIST_RDLOCK(&ast_event_subs[event_types[i]]);
 		AST_RWDLLIST_TRAVERSE(&ast_event_subs[event_types[i]], sub, entry) {
 			AST_LIST_TRAVERSE(&sub->ie_vals, ie_val, entry) {
-				if (!match_sub_ie_val_to_event(ie_val, &check_ie_vals)) {
+				if (has_check && !match_sub_ie_val_to_event(ie_val, &check_ie_vals)) {
 					/* The current subscription ie did not match an event ie. */
 					break;
 				}