diff --git a/SOPE/NGCards/iCalEventChanges.m b/SOPE/NGCards/iCalEventChanges.m
index 6886c75ab..b565a0870 100644
--- a/SOPE/NGCards/iCalEventChanges.m
+++ b/SOPE/NGCards/iCalEventChanges.m
@@ -124,8 +124,10 @@
   if(!IS_EQUAL([_from created], [_to created], isEqualToDate:))
     [updatedProperties addObject:@"created"];
   if(!IS_EQUAL([_from lastModified], [_to lastModified], isEqualToDate:))
-    [updatedProperties addObject:@"lastModified"];
-  if(![_from durationAsTimeInterval] == [_to durationAsTimeInterval])
+    [updatedProperties addObject:@"timeStampAsDate"];
+  if(!IS_EQUAL([_from timeStampAsDate], [_to timeStampAsDate], isEqualToDate:))
+    [updatedProperties addObject:@"timeStampAsDate"];
+  if([_from durationAsTimeInterval] != [_to durationAsTimeInterval])
     [updatedProperties addObject:@"duration"];
   if(!IS_EQUAL([_from summary], [_to summary], isEqualToString:))
     [updatedProperties addObject:@"summary"];
@@ -145,6 +147,8 @@
     [updatedProperties addObject:@"organizer"];
   if(!IS_EQUAL([_from recurrenceRules], [_to recurrenceRules], isEqual:))
     [updatedProperties addObject:@"rrule"];
+  if(!IS_EQUAL([_from recurrenceId], [_to recurrenceId], isEqualToDate:))
+    [updatedProperties addObject:@"rid"];
   if(!IS_EQUAL([_from exceptionRules], [_to exceptionRules], isEqual:))
     [updatedProperties addObject:@"exrule"];
   if(!IS_EQUAL([_from exceptionDates], [_to exceptionDates], isEqual:))
diff --git a/SoObjects/Appointments/SOGoAppointmentObject.m b/SoObjects/Appointments/SOGoAppointmentObject.m
index 39f07a0b3..6ae386869 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.m
+++ b/SoObjects/Appointments/SOGoAppointmentObject.m
@@ -191,11 +191,13 @@
       iCalCalendar *iCalendarToSave;
       iCalPerson *attendee;
       SOGoUser *user;
+      WORequest *rq;
 
       iCalendarToSave = nil;
       user = [SOGoUser userWithLogin: theUID];
       attendeeObject = [self _lookupEvent: [newEvent uid] forUID: theUID];
       attendee = [newEvent userAsAttendee: user];
+      rq = [context request];
 
       // If the atttende's role is NON-PARTICIPANT, we write nothing to its calendar
       if ([[attendee role] caseInsensitiveCompare: @"NON-PARTICIPANT"] == NSOrderedSame)
@@ -217,8 +219,9 @@
 
           return;
         }
-
-      if ([newEvent recurrenceId])
+      
+      
+      if ([newEvent recurrenceId] && ![rq isICal4] && ![rq isICal])
         {
           // We must add an occurence to a non-existing event.
           if ([attendeeObject isNew])
diff --git a/SoObjects/Appointments/iCalEventChanges+SOGo.m b/SoObjects/Appointments/iCalEventChanges+SOGo.m
index ca85e925d..f07c42a1e 100644
--- a/SoObjects/Appointments/iCalEventChanges+SOGo.m
+++ b/SoObjects/Appointments/iCalEventChanges+SOGo.m
@@ -30,7 +30,7 @@
   static NSString *properties[] = {@"organizer", @"startDate", @"endDate",
                                    @"due", @"duration", @"summary",
                                    @"rdate", @"rrule", @"exdate", @"exrule",
-                                   @"status", @"location",
+                                   @"status", @"location", @"rid", @"timeStampAsDate",
                                    nil};
   NSString **currentProperty;
   BOOL updateRequired;