diff --git a/Classes/LinphoneUI/UIChatNotifiedEventCell.m b/Classes/LinphoneUI/UIChatNotifiedEventCell.m
index a9af7a018..81b401474 100644
--- a/Classes/LinphoneUI/UIChatNotifiedEventCell.m
+++ b/Classes/LinphoneUI/UIChatNotifiedEventCell.m
@@ -61,7 +61,7 @@ static const CGFloat NOTIFIED_CELL_HEIGHT = 44;
 	NSString *eventString;
 	switch (linphone_event_log_get_type(event)) {
 		case LinphoneEventLogTypeConferenceSubjectChanged: {
-			NSString *subject = [NSString stringWithUTF8String:linphone_event_log_get_subject(event)];
+			NSString *subject = [NSString stringWithUTF8String:linphone_event_log_get_subject(event) ?: LINPHONE_DUMMY_SUBJECT];
 			NSString *formatedString = [NSString stringWithFormat:@"Chat room subject has changed to : %@", subject];
 			eventString = NSLocalizedString(formatedString, nil);
 			break;
diff --git a/submodules/linphone b/submodules/linphone
index 94a51d3ec..d7bc4b66a 160000
--- a/submodules/linphone
+++ b/submodules/linphone
@@ -1 +1 @@
-Subproject commit 94a51d3ec1b7dd69fd595e1eab50fda72c33dbda
+Subproject commit d7bc4b66ac414e6b6b5c0cd30bedcbcde4a9c05b