diff --git a/SoObjects/Appointments/SOGoCalendarComponent.h b/SoObjects/Appointments/SOGoCalendarComponent.h
index 3ecb0d007..761728c16 100644
--- a/SoObjects/Appointments/SOGoCalendarComponent.h
+++ b/SoObjects/Appointments/SOGoCalendarComponent.h
@@ -30,6 +30,7 @@
 @class NSString;
 
 @class iCalCalendar;
+@class iCalEntityObject;
 @class iCalEvent;
 @class iCalPerson;
 @class iCalRepeatableEntityObject;