diff --git a/ChangeLog b/ChangeLog
index f9a1ce434..e0a3bda96 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,7 +16,8 @@
 	([UIxMailPartICalViewer -declineLink])
 	([UIxMailPartICalViewer -tentativeLink]): removed useless methods.
 
-	* UI/MailPartViewers/UIxMailPartICalAction.m ([UIxMailPartICalAction -addToCalendarAction])
+	* UI/MailPartViewers/UIxMailPartICalAction.m
+	([UIxMailPartICalAction -addToCalendarAction])
 	([UIxMailPartICalAction -deleteFromCalendarAction]): new stub
 	methods.
 
diff --git a/SOPE/NGCards/ChangeLog b/SOPE/NGCards/ChangeLog
index 549ad5a29..ec0c0c542 100644
--- a/SOPE/NGCards/ChangeLog
+++ b/SOPE/NGCards/ChangeLog
@@ -1,3 +1,10 @@
+2007-11-12  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
+
+	* iCalTimeZonePeriod.m ([iCalTimeZonePeriod
+	-occurenceForDate:refDate]): added support for timezone periods
+	which do not contain a recurrence rule, such as the one provided
+	by iCal.
+
 2007-11-02  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
 
 	* iCalDateHolder.m ([iCalDateHolder -awakeAfterUsingSaxDecoder:]):
diff --git a/SOPE/NGCards/iCalTimeZonePeriod.m b/SOPE/NGCards/iCalTimeZonePeriod.m
index 29bd9bb17..dc1f611fd 100644
--- a/SOPE/NGCards/iCalTimeZonePeriod.m
+++ b/SOPE/NGCards/iCalTimeZonePeriod.m
@@ -99,35 +99,48 @@
   return dayOfWeek;
 }
 
-- (NSCalendarDate *) occurenceForDate: (NSCalendarDate *) refDate;
+- (NSCalendarDate *) _occurenceForDate: (NSCalendarDate *) refDate
+			       byRRule: (iCalRecurrenceRule *) rrule
 {
   NSCalendarDate *tmpDate;
-  iCalRecurrenceRule *rrule;
   NSString *byDay;
   int dayOfWeek, dateDayOfWeek, offset, pos;
 
-  rrule = (iCalRecurrenceRule *) [self uniqueChildWithTag: @"rrule"];
   byDay = [rrule namedValue: @"byday"];
   dayOfWeek = [self dayOfWeekFromRruleDay: [rrule byDayMask]];
   pos = [[byDay substringToIndex: 2] intValue];
   if (!pos)
     pos = 1;
 
-  tmpDate = [NSCalendarDate
-              dateWithYear: [refDate yearOfCommonEra]
-              month: [[rrule namedValue: @"bymonth"] intValue]
-              day: 1 hour: 0 minute: 0 second: 0
-              timeZone: [NSTimeZone timeZoneWithName: @"GMT"]];
+  tmpDate = [NSCalendarDate dateWithYear: [refDate yearOfCommonEra]
+			    month: [[rrule namedValue: @"bymonth"] intValue]
+			    day: 1 hour: 0 minute: 0 second: 0
+			    timeZone: [NSTimeZone timeZoneWithName: @"GMT"]];
   tmpDate = [tmpDate addYear: 0 month: ((pos > 0) ? 0 : 1)
-                     day: 0 hour: 0 minute: 0
-                     second: -[self _secondsOfOffset: @"tzoffsetfrom"]];
+		     day: 0 hour: 0 minute: 0
+		     second: -[self _secondsOfOffset: @"tzoffsetfrom"]];
   dateDayOfWeek = [tmpDate dayOfWeek];
   offset = (dayOfWeek - dateDayOfWeek);
   if (pos > 0 && offset < 0)
     offset += 7;
   offset += (pos * 7);
   tmpDate = [tmpDate addYear: 0 month: 0 day: offset
-                     hour: 0 minute: 0 second: 0];
+		     hour: 0 minute: 0 second: 0];
+
+  return tmpDate;
+}
+
+- (NSCalendarDate *) occurenceForDate: (NSCalendarDate *) refDate;
+{
+  NSCalendarDate *tmpDate;
+  iCalRecurrenceRule *rrule;
+
+  rrule = (iCalRecurrenceRule *) [self uniqueChildWithTag: @"rrule"];
+  if ([rrule isVoid])
+    tmpDate
+      = [(iCalDateTime *) [self uniqueChildWithTag: @"dtstart"] dateTime];
+  else
+    tmpDate = [self _occurenceForDate: refDate byRRule: rrule];
 
   return tmpDate;
 }
diff --git a/SoObjects/Appointments/SOGoAppointmentObject.m b/SoObjects/Appointments/SOGoAppointmentObject.m
index 7cc44e230..cac6db9ef 100644
--- a/SoObjects/Appointments/SOGoAppointmentObject.m
+++ b/SoObjects/Appointments/SOGoAppointmentObject.m
@@ -252,36 +252,32 @@
       uid = [self getUIDForICalPerson: organizer];
       if (!uid)
 	uid = [self ownerInContext: nil];
-      if (uid) {
-	if (![storeUIDs containsObject:uid])
-	  [storeUIDs addObject:uid];
-	[removedUIDs removeObject:uid];
-      }
+      if (uid)
+	{
+	  [storeUIDs addObjectUniquely: uid];
+	  [removedUIDs removeObject: uid];
+	}
 
       /* organizer might have changed completely */
 
-      if (oldApt && ([props containsObject: @"organizer"])) {
-	uid = [self getUIDForICalPerson:[oldApt organizer]];
-	if (uid) {
-	  if (![storeUIDs containsObject:uid]) {
-	    if (![removedUIDs containsObject:uid]) {
-	      [removedUIDs addObject:uid];
-	    }
-	  }
+      if (oldApt && ([props containsObject: @"organizer"]))
+	{
+	  uid = [self getUIDForICalPerson: [oldApt organizer]];
+	  if (uid && ![storeUIDs containsObject: uid])
+	    [removedUIDs addObjectUniquely: uid];
 	}
-      }
 
-      [self debugWithFormat:@"UID ops:\n  store: %@\n  remove: %@",
+      [self debugWithFormat: @"UID ops:\n  store: %@\n  remove: %@",
 	    storeUIDs, removedUIDs];
 
       /* if time did change, all participants have to re-decide ...
        * ... exception from that rule: the organizer
        */
 
-      if (oldApt != nil &&
-	  ([props containsObject: @"startDate"] ||
-	   [props containsObject: @"endDate"]   ||
-	   [props containsObject: @"duration"]))
+      if (oldApt
+	  && ([props containsObject: @"startDate"]
+	      || [props containsObject: @"endDate"]
+	      || [props containsObject: @"duration"]))
 	{
 	  NSArray  *ps;
 	  unsigned i, count;
@@ -320,15 +316,16 @@
 		andNewObject: newApt
 		toAttendees: attendees];
 
-	  if (updateForcesReconsider) {
-	    attendees = [NSMutableArray arrayWithArray:[newApt attendees]];
-	    [attendees removeObjectsInArray:[changes insertedAttendees]];
-	    [attendees removePerson:organizer];
-	    [self sendEMailUsingTemplateNamed: @"Update"
-		  forOldObject: oldApt
-		  andNewObject: newApt
-		  toAttendees: attendees];
-	  }
+	  if (updateForcesReconsider)
+	    {
+	      attendees = [NSMutableArray arrayWithArray:[newApt attendees]];
+	      [attendees removeObjectsInArray:[changes insertedAttendees]];
+	      [attendees removePerson:organizer];
+	      [self sendEMailUsingTemplateNamed: @"Update"
+		    forOldObject: oldApt
+		    andNewObject: newApt
+		    toAttendees: attendees];
+	    }
 
 	  attendees
 	    = [NSMutableArray arrayWithArray: [changes deletedAttendees]];
@@ -393,8 +390,8 @@
 	  && [self _aptIsStillRelevant: apt])
 	{
 	  /* send notification email to attendees excluding organizer */
-	  attendees = [NSMutableArray arrayWithArray:[apt attendees]];
-	  [attendees removePerson:[apt organizer]];
+	  attendees = [NSMutableArray arrayWithArray: [apt attendees]];
+	  [attendees removePerson: [apt organizer]];
   
 	  /* flag appointment as being cancelled */
 	  [(iCalCalendar *) [apt parent] setMethod: @"cancel"];
diff --git a/SoObjects/Appointments/SOGoAptMailNotification.m b/SoObjects/Appointments/SOGoAptMailNotification.m
index 912c3a0e2..b08bf74df 100644
--- a/SoObjects/Appointments/SOGoAptMailNotification.m
+++ b/SoObjects/Appointments/SOGoAptMailNotification.m
@@ -82,6 +82,7 @@ static NSTimeZone     *EST = nil;
 - (NSString *)homePageURL {
   return self->homePageURL;
 }
+
 - (void)setHomePageURL:(NSString *)_homePageURL {
   ASSIGN(self->homePageURL, _homePageURL);
 }