diff --git a/SoObjects/Appointments/SOGoAppointmentFolder.m b/SoObjects/Appointments/SOGoAppointmentFolder.m
index 09594a465..5aaa3938a 100644
--- a/SoObjects/Appointments/SOGoAppointmentFolder.m
+++ b/SoObjects/Appointments/SOGoAppointmentFolder.m
@@ -1888,18 +1888,18 @@ static Class sogoAppointmentFolderKlass = Nil;
   NSArray *elements;
   NSString *method, *filename;
   SOGoAppointmentObject *apt;
-
+  
   filename = [NSString stringWithFormat: @"%@.ics", [event uid]];
   apt = [SOGoAppointmentObject objectWithName: filename
 			       andContent: iCalString
 			       inContainer: self];
   method = [[event parent] method];
   if ([method isEqualToString: @"REQUEST"])
-    elements = [apt postCalDAVEventRequestTo: recipients];
+    elements = [apt postCalDAVEventRequestTo: recipients  from: originator];
   else if ([method isEqualToString: @"REPLY"])
-    elements = [apt postCalDAVEventReplyTo: recipients];
+    elements = [apt postCalDAVEventReplyTo: recipients  from: originator];
   else if ([method isEqualToString: @"CANCEL"])
-    elements = [apt postCalDAVEventCancelTo: recipients];
+    elements = [apt postCalDAVEventCancelTo: recipients  from: originator];
   else
     elements = nil;
 
@@ -1970,6 +1970,10 @@ static Class sogoAppointmentFolderKlass = Nil;
   if ([cType hasPrefix: @"text/calendar"])
     {
       originator = [request headerForKey: @"originator"];
+
+      if ([[originator lowercaseString] hasPrefix: @"mailto:"])
+	originator = [originator substringFromIndex: 7];  
+
       recipients = [[request headerForKey: @"recipient"]
 		     componentsSeparatedByString: @", "];
       obj = [self caldavScheduleRequest: [request contentAsString]
diff --git a/SoObjects/Appointments/SOGoAppointmentObject.h b/SoObjects/Appointments/SOGoAppointmentObject.h
index 37f63201b..e6be8fd0c 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.h
+++ b/SoObjects/Appointments/SOGoAppointmentObject.h
@@ -48,11 +48,11 @@
 
 - (NSException *) changeParticipationStatus: (NSString *) _status;
 
-- (void) takeAttendeeStatus: (iCalPerson *) attendee;
+- (void) takeAttendeeStatus: (iCalPerson *) attendee  from: (NSString *) originator;
 
-- (NSArray *) postCalDAVEventRequestTo: (NSArray *) recipients;
-- (NSArray *) postCalDAVEventReplyTo: (NSArray *) recipients;
-- (NSArray *) postCalDAVEventCancelTo: (NSArray *) recipients;
+- (NSArray *) postCalDAVEventRequestTo: (NSArray *) recipients  from: (NSString *) originator;
+- (NSArray *) postCalDAVEventReplyTo: (NSArray *) recipients  from: (NSString *) originator;
+- (NSArray *) postCalDAVEventCancelTo: (NSArray *) recipients  from: (NSString *) originator;
 
 /* "iCal multifolder saves" */
 
diff --git a/SoObjects/Appointments/SOGoAppointmentObject.m b/SoObjects/Appointments/SOGoAppointmentObject.m
index cf83d2f73..97faf8401 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.m
+++ b/SoObjects/Appointments/SOGoAppointmentObject.m
@@ -362,6 +362,17 @@
   [super saveComponent: newEvent];
 }
 
+//
+// This method is used to update the status of an attendee.
+//
+// - theOwnerUser is owner of the calendar where the attendee
+//   participation state has changed.
+// - uid is the actual UID of the user for whom we must
+//   update the calendar event (with the participation change)
+//
+// This method is called multiple times, in order to update the
+// status of the attendee in calendars for the particular event UID.
+// 
 - (NSException *) _updateAttendee: (iCalPerson *) attendee
                         ownerUser: (SOGoUser *) theOwnerUser
 		      forEventUID: (NSString *) eventUID
@@ -409,14 +420,21 @@
   return error;
 }
 
+
+//
+// This method is invoked only from the SOGo Web interface.
+//
+// - theOwnerUser is owner of the calendar where the attendee
+//   participation state has changed.
+//
 - (NSException *) _handleAttendee: (iCalPerson *) attendee
                         ownerUser: (SOGoUser *) theOwnerUser
 		     statusChange: (NSString *) newStatus
 			  inEvent: (iCalEvent *) event
 {
   NSString *newContent, *currentStatus, *currentUser, *organizerUID;
-  NSException *ex;
   SOGoUser *ownerUser;
+  NSException *ex;
 
   ex = nil;
 
@@ -442,14 +460,17 @@
       newContent = [[event parent] versitString];
       ex = [self saveContentString: newContent];
 
-
+      // If the current user isn't the organizer of the event
+      // that has just been updated, we update the event and
+      // send a notification
       ownerUser = [SOGoUser userWithLogin: owner roles: nil];
       if (!(ex || [event userIsOrganizer: ownerUser]))
 	{
 	  if ([[attendee rsvp] isEqualToString: @"true"]
 	      && [event isStillRelevant])
-	    [self sendResponseToOrganizer: event];
-	
+	    [self sendResponseToOrganizer: event
+		  from: ownerUser];
+	  
 	  organizerUID = [[event organizer] uid];
 	  if (organizerUID)
 	    ex = [self _updateAttendee: attendee
@@ -514,6 +535,7 @@
 }
 
 - (NSArray *) postCalDAVEventRequestTo: (NSArray *) recipients
+				  from: (NSString *) originator
 {
   NSMutableArray *elements;
   NSEnumerator *recipientsEnum;
@@ -546,6 +568,7 @@
 }
 
 - (NSArray *) postCalDAVEventCancelTo: (NSArray *) recipients
+				 from: (NSString *) originator
 {
   NSMutableArray *elements;
   NSEnumerator *recipientsEnum;
@@ -577,7 +600,19 @@
   return elements;
 }
 
+
+//
+// This method is invoked by CalDAV clients such as
+// Mozilla Lightning. We assume the SENT-BY has
+// already been added, if required.
+//
+// It is used to updated the status of an attendee.
+// The originator is the actualy owner of the calendar
+// where the update took place. The status must then
+// be propagated to the organizer and the other attendees.
+//
 - (void) takeAttendeeStatus: (iCalPerson *) attendee
+		       from: (NSString *) originator
 {
   iCalPerson *localAttendee;
   iCalEvent *event;
@@ -595,17 +630,23 @@
      iCalPerson *att;
      NSString *uid;
      int i;
+     
+     ownerUser = [SOGoUser userWithLogin:[[LDAPUserManager sharedUserManager]
+					   getUIDForEmail: originator]
+			   roles: nil];
 
-     // We update for the organizer
-     ownerUser = [context activeUser];
-
-     [self _updateAttendee: attendee
-	   ownerUser: ownerUser
-	   forEventUID: [event uid]
-	   withSequence: [event sequence]
-	   forUID: [[SOGoUser userWithLogin: owner roles: nil] login]
-	   shouldAddSentBy: NO];
-
+     // We update the copy of the organizer, only
+     // if it's a local user.
+#warning add a check for only local users
+     uid = [[event organizer] uid];
+     if (uid)
+       [self _updateAttendee: attendee
+	     ownerUser: ownerUser
+	     forEventUID: [event uid]
+	     withSequence: [event sequence]
+	     forUID: uid
+	     shouldAddSentBy: NO];
+    
       attendees = [event attendees];
 
       for (i = 0; i < [attendees count]; i++)
@@ -619,6 +660,12 @@
 
 	  if (uid)
 	    {		
+	      // We skip the update that correspond to the originator
+	      // since the CalDAV client will already have updated
+	      // the actual event.
+	      if ([ownerUser hasEmail: [att rfc822Email]]) 
+		continue;
+
 	      [self _updateAttendee: attendee
 		    ownerUser: ownerUser
 		    forEventUID: [event uid]
@@ -635,6 +682,7 @@
 }
 
 - (NSArray *) postCalDAVEventReplyTo: (NSArray *) recipients
+				from: (NSString *) originator
 {
   NSMutableArray *elements;
   NSEnumerator *recipientsEnum;
@@ -643,10 +691,15 @@
   iCalPerson *attendee, *person;
   SOGoAppointmentObject *recipientEvent;
   SOGoUser *ownerUser;
+  NSString *email;
 
   elements = [NSMutableArray array];
   event = [self component: NO secure: NO];
-  ownerUser = [SOGoUser userWithLogin: owner roles: nil];
+  //ownerUser = [SOGoUser userWithLogin: owner roles: nil]; 
+
+  ownerUser = [SOGoUser userWithLogin: [[LDAPUserManager sharedUserManager]
+					 getUIDForEmail: originator]
+			roles: nil];
   attendee = [event findParticipant: ownerUser];
   eventUID = [event uid];
 
@@ -663,9 +716,12 @@
 	    if ([recipientEvent isNew])
 	      [recipientEvent saveComponent: event];
 	    else
-	      [recipientEvent takeAttendeeStatus: attendee];
+	      [recipientEvent takeAttendeeStatus: attendee
+			      from: originator];
 	  }
-	[self sendIMIPReplyForEvent: event to: person];
+	[self sendIMIPReplyForEvent: event
+	      from: ownerUser
+	      to: person];
 	[person release];
 	[elements
 	  addObject: [self _caldavSuccessCodeWithRecipient: recipient]];
@@ -674,6 +730,9 @@
   return elements;
 }
 
+//
+// This method is invoked only from the SOGo Web interface.
+//
 - (NSException *) changeParticipationStatus: (NSString *) _status
 {
   iCalEvent *event;
@@ -686,7 +745,13 @@
   event = [self component: NO secure: NO];
   if (event)
     {
+      // owerUser will actually be the owner of the calendar
+      // where the participation change on the event has
+      // actually occured. The particpation change will of
+      // course be on the attendee that is the owner of the
+      // calendar where the participation change has occured.
       ownerUser = [SOGoUser userWithLogin: owner roles: nil];
+     
       attendee = [event findParticipant: ownerUser];
       if (attendee)
 	ex = [self _handleAttendee: attendee
diff --git a/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.html b/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.html
index c4e107131..9c7fc4cd5 100644
--- a/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.html
+++ b/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.html
@@ -1,2 +1,2 @@
 <#IsSubject>Gebeurtenis geannuleerd: <#summary/></#IsSubject>
-<#IsBody><#organizer/> heeft deze gebeurtenis geannuleerd: « <#summary/> ».</#IsBody>
\ No newline at end of file
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>heeft deze gebeurtenis geannuleerd: « <#summary/> ».</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.wod b/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.wod
+++ b/SoObjects/Appointments/SOGoAptMailDutchDeletion.wo/SOGoAptMailDutchDeletion.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.html b/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.html
index 8e2bf817d..02a92f4c2 100644
--- a/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.html
+++ b/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.html
@@ -1,2 +1,2 @@
 <#IsSubject>Uitnodiging voor gebeurtenis: <#summary/></#IsSubject>
-<#IsBody><#organizer/> heeft u uitgenodigd voor <#summary/>.</#IsBody>
\ No newline at end of file
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>heeft u uitgenodigd voor <#summary/>.</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.wod b/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.wod
+++ b/SoObjects/Appointments/SOGoAptMailDutchInvitation.wo/SOGoAptMailDutchInvitation.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.html b/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.html
index b28fed22d..a025bde4d 100644
--- a/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.html
+++ b/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.html
@@ -1,2 +1,2 @@
 <#IsSubject>Événement annulé : « <#summary/> »</#IsSubject>
-<#IsBody><#organizer/> a annulé cet événement : « <#summary/> ».</#IsBody>
\ No newline at end of file
+<#IsBody><#organizer/> <#HasSentBy>(envoyé par <#sentBy/>) </#HasSentBy>a annulé cet événement : « <#summary/> ».</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.wod b/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.wod
+++ b/SoObjects/Appointments/SOGoAptMailFrenchDeletion.wo/SOGoAptMailFrenchDeletion.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.html b/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.html
index 835952a13..8a4ec4b82 100644
--- a/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.html
+++ b/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.html
@@ -1,2 +1,2 @@
 <#IsSubject>Invitation : <#summary/></#IsSubject>
-<#IsBody><#organizer/> vous a invité à « <#summary/> ».</#IsBody>
+<#IsBody><#organizer/> <#HasSentBy>(envoyé par <#sentBy/>) </#HasSentBy>vous a invité à « <#summary/> ».</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.wod b/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.wod
+++ b/SoObjects/Appointments/SOGoAptMailFrenchInvitation.wo/SOGoAptMailFrenchInvitation.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.html b/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.html
index 43b8d5c9b..3c0264a20 100644
--- a/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.html
+++ b/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.html
@@ -1,2 +1,2 @@
 <#IsSubject>Termin abgesagt: <#summary/></#IsSubject>
-<#IsBody><#organizer/> hat diesen Termin abgesagt: <#summary/></#IsBody>
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>hat diesen Termin abgesagt: <#summary/></#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.wod b/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.wod
+++ b/SoObjects/Appointments/SOGoAptMailGermanDeletion.wo/SOGoAptMailGermanDeletion.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.html b/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.html
index 9500e1fa9..3f6163919 100644
--- a/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.html
+++ b/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.html
@@ -1,2 +1,2 @@
 <#IsSubject>Termineinladung: <#summary/></#IsSubject>
-<#IsBody><#organizer/> hat Sie zu <#summary/> eingeladen.</#IsBody>
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>hat Sie zu <#summary/> eingeladen.</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.wod b/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.wod
+++ b/SoObjects/Appointments/SOGoAptMailGermanInvitation.wo/SOGoAptMailGermanInvitation.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.html b/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.html
index ee71e81e4..754921b66 100644
--- a/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.html
+++ b/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.html
@@ -1,2 +1,2 @@
 <#IsSubject>Evento cancellato : " <#summary/> "</#IsSubject>
-<#IsBody><#organizer/> ha cancellato questo elemento: " <#summary/> ".</#IsBody>
\ No newline at end of file
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>ha cancellato questo elemento: " <#summary/> ".</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.wod b/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.wod
+++ b/SoObjects/Appointments/SOGoAptMailItalianDeletion.wo/SOGoAptMailItalianDeletion.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.html b/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.html
index 131c012b8..7dbc92fb8 100644
--- a/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.html
+++ b/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.html
@@ -1,2 +1,2 @@
 <#IsSubject>Invito evento: <#summary/></#IsSubject>
-<#IsBody>Si è stati invitati da <#organizer> a <#summary/>.</#IsBody>
\ No newline at end of file
+<#IsBody>Si è stati invitati da <#organizer> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>a <#summary/>.</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.wod b/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.wod
index 6d3d52eca..66b51444b 100644
--- a/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.wod
+++ b/SoObjects/Appointments/SOGoAptMailItalianInvitation.wo/SOGoAptMailItalianInvitation.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
diff --git a/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.html b/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.html
index f70c7ff33..97636c29a 100644
--- a/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.html
+++ b/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.html
@@ -1,2 +1,2 @@
 <#IsSubject>Evento cancelado: <#summary/></#IsSubject>
-<#IsBody><#organizer/> ha cancelado este evento: « <#summary/> ».</#IsBody>
\ No newline at end of file
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>ha cancelado este evento: « <#summary/> ».</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.wod b/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.wod
+++ b/SoObjects/Appointments/SOGoAptMailSpanishDeletion.wo/SOGoAptMailSpanishDeletion.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.html b/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.html
index 88d568790..22ddafe96 100644
--- a/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.html
+++ b/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.html
@@ -1,2 +1,2 @@
 <#IsSubject>Invitación a evento: <#summary/></#IsSubject>
-<#IsBody><#organizer/> le ha invitado a <#summary/>.</#IsBody>
+<#IsBody><#organizer/> <#HasSentBy>(sent by <#sentBy/>) </#HasSentBy>le ha invitado a <#summary/>.</#IsBody>
diff --git a/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.wod b/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.wod
index 6d3d52eca..92428f429 100644
--- a/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.wod
+++ b/SoObjects/Appointments/SOGoAptMailSpanishInvitation.wo/SOGoAptMailSpanishInvitation.wod
@@ -16,3 +16,12 @@ summary: WOString {
   value = summary;
   escapeHTML = NO;
 }
+
+HasSentBy: WOConditional {
+  condition = hasSentBy;
+}
+
+sentBy: WOString {
+  value = sentBy;
+  escapeHTML = NO;
+}
\ No newline at end of file
diff --git a/SoObjects/Appointments/SOGoCalendarComponent.h b/SoObjects/Appointments/SOGoCalendarComponent.h
index 2c3847dc5..a60ed016b 100644
--- a/SoObjects/Appointments/SOGoCalendarComponent.h
+++ b/SoObjects/Appointments/SOGoCalendarComponent.h
@@ -63,8 +63,10 @@
 			   forObject: (iCalRepeatableEntityObject *) object
                          toAttendees: (NSArray *) attendees;
 - (void) sendIMIPReplyForEvent: (iCalRepeatableEntityObject *) event
+			  from: (SOGoUser *) from
 			    to: (iCalPerson *) recipient;
-- (void) sendResponseToOrganizer: (iCalRepeatableEntityObject *) newComponent;
+- (void) sendResponseToOrganizer: (iCalRepeatableEntityObject *) newComponent
+			   from: (SOGoUser *) owner;
 
 // - (BOOL) isOrganizerOrOwner: (SOGoUser *) user;
 
diff --git a/SoObjects/Appointments/SOGoCalendarComponent.m b/SoObjects/Appointments/SOGoCalendarComponent.m
index 94a3c5bd3..d94176120 100644
--- a/SoObjects/Appointments/SOGoCalendarComponent.m
+++ b/SoObjects/Appointments/SOGoCalendarComponent.m
@@ -583,6 +583,7 @@ _occurenceHasID (iCalRepeatableEntityObject *occurence, NSString *recID)
 
 #warning fix this when sendEmailUsing blabla has been cleaned up
 - (void) sendIMIPReplyForEvent: (iCalRepeatableEntityObject *) event
+			  from: (SOGoUser *) from
 			    to: (iCalPerson *) recipient
 {
   NSString *pageName, *language, *mailDate, *email;
@@ -602,7 +603,8 @@ _occurenceHasID (iCalRepeatableEntityObject *occurence, NSString *recID)
       /* get WOApplication instance */
       app = [WOApplication application];
 
-      ownerUser = [SOGoUser userWithLogin: owner roles: nil];
+      //ownerUser = [SOGoUser userWithLogin: owner roles: nil];
+      ownerUser = from;
       language = [ownerUser language];
       /* create page name */
       pageName
@@ -672,6 +674,7 @@ _occurenceHasID (iCalRepeatableEntityObject *occurence, NSString *recID)
 }
 
 - (void) sendResponseToOrganizer: (iCalRepeatableEntityObject *) newComponent
+			    from: (SOGoUser *) from
 {
   iCalPerson *organizer, *attendee;
   iCalEvent *event;
@@ -684,7 +687,7 @@ _occurenceHasID (iCalRepeatableEntityObject *occurence, NSString *recID)
       organizer = [event organizer];
       attendee = [event findParticipant: ownerUser];
       [event setAttendees: [NSArray arrayWithObject: attendee]];
-      [self sendIMIPReplyForEvent: event to: organizer];
+      [self sendIMIPReplyForEvent: event from: from to: organizer];
     }
 }
 
diff --git a/SoObjects/SOGo/SOGoUserDefaults.m b/SoObjects/SOGo/SOGoUserDefaults.m
index 74633ec4a..bba5b9d5f 100644
--- a/SoObjects/SOGo/SOGoUserDefaults.m
+++ b/SoObjects/SOGo/SOGoUserDefaults.m
@@ -275,10 +275,13 @@ static NSString *uidColumnName = @"c_uid";
 	      [d addEntriesFromDictionary: values];
 	      [d setObject: uid  forKey: @"uid"];
 
+#warning reenable when the code to use the SOGoUserManager is finished	      
+#if 0
 	      [[NSDistributedNotificationCenter defaultCenter]
 		postNotificationName: ([fieldName isEqualToString: @"c_defaults"] ? @"SOGoUserDefaultsHaveChanged" : @"SOGoUserSettingsHaveChanged")
 		object: nil
 		userInfo: d];
+#endif
 	      [d release];
 	      
 	      if ([[channel adaptorContext] hasOpenTransaction])
diff --git a/UI/MailPartViewers/UIxMailPartICalActions.m b/UI/MailPartViewers/UIxMailPartICalActions.m
index 5ad40a4e3..1ce6137c7 100644
--- a/UI/MailPartViewers/UIxMailPartICalActions.m
+++ b/UI/MailPartViewers/UIxMailPartICalActions.m
@@ -1,6 +1,6 @@
 /* UIxMailPartICalActions.m - this file is part of SOGo
  *
- * Copyright (C) 2007 Inverse inc.
+ * Copyright (C) 2007-2008 Inverse inc.
  *
  * Author: Wolfgang Sourdeau <wsourdeau@inverse.ca>
  *
@@ -36,6 +36,7 @@
 
 #import <NGImap4/NGImap4EnvelopeAddress.h>
 
+#import <SoObjects/Appointments/iCalEvent+SOGo.h>
 #import <SoObjects/Appointments/iCalPerson+SOGo.h>
 #import <SoObjects/Appointments/SOGoAppointmentObject.h>
 #import <SoObjects/Appointments/SOGoAppointmentFolder.h>
@@ -168,16 +169,18 @@
 
 #warning this is code copied from SOGoAppointmentObject...
 - (void) _updateAttendee: (iCalPerson *) attendee
-	    withSequence: (NSNumber *) sequence
-	       andCalUID: (NSString *) calUID
-		  forUID: (NSString *) uid
+               ownerUser: (SOGoUser *) theOwnerUser
+	       forEventUID: (NSString *) eventUID
+	       withSequence: (NSNumber *) sequence
+	       forUID: (NSString *) uid
+	       shouldAddSentBy: (BOOL) b
 {
   SOGoAppointmentObject *eventObject;
   iCalEvent *event;
   iCalPerson *otherAttendee;
   NSString *iCalString;
 
-  eventObject = [self _eventObjectWithUID: calUID
+  eventObject = [self _eventObjectWithUID: eventUID
 		      forUser: [SOGoUser userWithLogin: uid roles: nil]];
   if (![eventObject isNew])
     {
@@ -185,9 +188,22 @@
       if ([[event sequence] compare: sequence]
 	  == NSOrderedSame)
 	{
-	  otherAttendee
-	    = [event findParticipantWithEmail: [attendee rfc822Email]];
+	  SOGoUser *currentUser;
+	  
+	  otherAttendee = [event findParticipant: theOwnerUser];
 	  [otherAttendee setPartStat: [attendee partStat]];
+	  
+	  // If one has accepted / declined an invitation on behalf of
+	  // the attendee, we add the user to the SENT-BY attribute.
+	  currentUser = [context activeUser];
+	  if (b && ![[currentUser login] isEqualToString: [theOwnerUser login]])
+	    {
+	      NSString *currentEmail;
+	      currentEmail = [[currentUser allEmails] objectAtIndex: 0];
+	      [otherAttendee addAttribute: @"SENT-BY"
+			     value: [NSString stringWithFormat: @"\"MAILTO:%@\"", currentEmail]];
+	    }
+
 	  iCalString = [[event parent] versitString];
 	  [eventObject saveContentString: iCalString];
 	}
@@ -219,12 +235,50 @@
       else
 	rsvp = nil;
       [eventObject saveContentString: [calendar versitString]];
-      if ([rsvp isEqualToString: @"true"])
-	[eventObject sendResponseToOrganizer: chosenEvent];
+      if ([rsvp isEqualToString: @"true"] &&
+	  [chosenEvent isStillRelevant])
+	[eventObject sendResponseToOrganizer: chosenEvent
+		     from: [context activeUser]];
       organizerUID = [[chosenEvent organizer] uid];
       if (organizerUID)
-	[self _updateAttendee: user withSequence: [chosenEvent sequence]
-	      andCalUID: [chosenEvent uid] forUID: organizerUID];
+	[self _updateAttendee: user
+	      ownerUser: [context activeUser]
+	      forEventUID: [chosenEvent uid]
+	      withSequence: [chosenEvent sequence]
+	      forUID: organizerUID
+	      shouldAddSentBy: YES];
+
+      // We update the calendar of all participants that are
+      // local to the system. This is useful in case user A accepts
+      // invitation from organizer B and users C, D, E who are also
+      // attendees need to verify if A has accepted.
+      NSArray *attendees;
+      iCalPerson *att;
+      NSString *uid;
+      int i;
+
+      attendees = [chosenEvent attendees];
+
+      for (i = 0; i < [attendees count]; i++)
+	{
+	  att = [attendees objectAtIndex: i];
+	  
+	  if (att == user) continue;
+	  
+	  uid = [[LDAPUserManager sharedUserManager]
+		  getUIDForEmail: [att rfc822Email]];
+
+	  if (uid)
+	    {
+	      [self _updateAttendee: user
+		    ownerUser: [context activeUser]
+		    forEventUID: [chosenEvent uid]
+		    withSequence: [chosenEvent sequence]
+		    forUID: uid
+		    shouldAddSentBy: YES];
+	    }
+	}
+
       response = [self responseWith204];
     }
   else