diff --git a/ChangeLog b/ChangeLog
index 90e353eeb..b4a38934f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2008-11-18  Ludovic Marcotte  <lmarcotte@inverse.ca>
+
+        * SoObjects/Appointments/SOGoAppointmentObject.m
+	Modified postCalDAVEventRequestTo: from: to handle
+	invitation updates from normal ones.
+
 2008-11-17  Ludovic Marcotte  <lmarcotte@inverse.ca>
 
         * Added back the appointment update notification
diff --git a/SoObjects/Appointments/SOGoAppointmentObject.m b/SoObjects/Appointments/SOGoAppointmentObject.m
index bd75fd20d..9e7b2d152 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.m
+++ b/SoObjects/Appointments/SOGoAppointmentObject.m
@@ -557,9 +557,10 @@
   NSMutableArray *elements;
   NSEnumerator *recipientsEnum;
   NSString *recipient, *uid;
-  iCalEvent *event;
+  iCalEvent *event, *oldEvent;
   iCalPerson *person;
-
+  BOOL isUpdate, hasChanged;
+  
   elements = [NSMutableArray array];
 
   event = [self component: NO secure: NO];
@@ -570,13 +571,37 @@
 	person = [iCalPerson new];
 	[person setValue: 0 to: recipient];
 	uid = [person uid];
-	if (uid)
-	  [self _addOrUpdateEvent: event forUID: uid];
+	oldEvent = nil;
+	hasChanged = YES;
+	isUpdate = NO;
+
+	if (uid) 
+	  {
+	    // We check if we must send an invitation update
+	    // rather than just a normal invitation
+	    SOGoAppointmentObject *oldEventObject;
+	    iCalEventChanges *changes;
+
+	    oldEventObject = [self _lookupEvent: [event uid] forUID: uid];
+	    oldEvent = [oldEventObject component: NO  secure: NO];
+	    changes = [event getChangesRelativeToEvent: oldEvent];
+
+	    if ([[oldEvent sequence] compare: [event sequence]] != NSOrderedSame)
+	      {
+		if ([changes sequenceShouldBeIncreased])
+		  isUpdate = YES;
+		else
+		  hasChanged = NO;
+	      }
+	    [self _addOrUpdateEvent: event forUID: uid];
+	  }
 #warning fix this when sendEmailUsing blabla has been cleaned up
-	[self sendEMailUsingTemplateNamed: @"Invitation"
-	      forObject: event
-	      previousObject: nil
-	      toAttendees: [NSArray arrayWithObject: person]];
+	if (hasChanged)
+	  [self sendEMailUsingTemplateNamed: (isUpdate ? @"Update" : @"Invitation")
+		forObject: event
+		previousObject: oldEvent
+		toAttendees: [NSArray arrayWithObject: person]];
+
 	[person release];
 	[elements
 	  addObject: [self _caldavSuccessCodeWithRecipient: recipient]];