diff --git a/UI/MailPartViewers/UIxMailPartMessageViewer.m b/UI/MailPartViewers/UIxMailPartMessageViewer.m
index fefff10fd..67052555d 100644
--- a/UI/MailPartViewers/UIxMailPartMessageViewer.m
+++ b/UI/MailPartViewers/UIxMailPartMessageViewer.m
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2007-2009 Inverse inc.
+  Copyright (C) 2007-2015 Inverse inc.
   Copyright (C) 2004-2005 SKYRIX Software AG
 
   This file is part of SOGo.
@@ -25,6 +25,8 @@
 
 #import <NGExtensions/NSString+Encoding.h>
 
+#import <NGObjWeb/WOResponse.h>
+
 #import <SoObjects/Mailer/NSData+Mail.h>
 #import <SoObjects/Mailer/NSString+Mail.h>