diff --git a/SOPE/NGCards/CardGroup.h b/SOPE/NGCards/CardGroup.h
index 1dfb6c7ef..2ef4adc46 100644
--- a/SOPE/NGCards/CardGroup.h
+++ b/SOPE/NGCards/CardGroup.h
@@ -49,7 +49,7 @@
 - (void) addChild: (CardElement *) aChild;
 - (void) addChildren: (NSArray *) someChildren;
 
-- (NSArray *) children;
+- (NSMutableArray *) children;
 - (CardElement *) firstChildWithTag: (NSString *) aTag;
 - (NSArray *) childrenWithTag: (NSString *) aTag;
 - (NSArray *) childrenWithAttribute: (NSString *) anAttribute
diff --git a/SOPE/NGCards/CardGroup.m b/SOPE/NGCards/CardGroup.m
index d1c8c2482..a608c47be 100644
--- a/SOPE/NGCards/CardGroup.m
+++ b/SOPE/NGCards/CardGroup.m
@@ -260,7 +260,7 @@ static NGCardsSaxHandler *sax = nil;
     [self addChild: currentChild];
 }
 
-- (NSArray *) children
+- (NSMutableArray *) children
 {
   return children;
 }
@@ -398,9 +398,20 @@ static NGCardsSaxHandler *sax = nil;
 - (id) copyWithZone: (NSZone *) aZone
 {
   CardGroup *new;
+  CardElement *newChild;
+  NSMutableArray *newChildren;
+  unsigned int count, max;
 
   new = [super copyWithZone: aZone];
-  [new setChildrenAsCopy: [children copyWithZone: aZone]];
+  newChildren = [NSMutableArray new];
+  max = [children count];
+  for (count = 0; count < max; count++)
+    {
+      newChild = [[children objectAtIndex: count] copyWithZone: aZone];
+      [newChildren addObject: newChild];
+    }
+  [new setChildrenAsCopy: newChildren];
+  [newChildren release];
 
   return new;
 }
@@ -410,9 +421,21 @@ static NGCardsSaxHandler *sax = nil;
 - (id) mutableCopyWithZone: (NSZone *) aZone
 {
   CardGroup *new;
+  CardElement *newChild;
+  NSMutableArray *newChildren;
+  unsigned int count, max;
 
   new = [super mutableCopyWithZone: aZone];
-  [new setChildrenAsCopy: [children mutableCopyWithZone: aZone]];
+  newChildren = [NSMutableArray new];
+  max = [children count];
+  for (count = 0; count < max; count++)
+    {
+      newChild
+	= [[children objectAtIndex: count] mutableCopyWithZone: aZone];
+      [newChildren addObject: newChild];
+    }
+  [new setChildrenAsCopy: newChildren];
+  [newChildren release];
 
   return new;
 }
diff --git a/SOPE/NGCards/ChangeLog b/SOPE/NGCards/ChangeLog
index 23000a161..7e6a37822 100644
--- a/SOPE/NGCards/ChangeLog
+++ b/SOPE/NGCards/ChangeLog
@@ -1,3 +1,17 @@
+2008-07-17  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
+
+	* iCalRepeatableEntityObject.m ([iCalRepeatableEntityObject
+	-addToExceptionDates:_rdate]): the iCalDateTime argument was
+	replaced with NSCalendarDate.
+
+	* iCalEntityObject.m ([iCalEntityObject
+	-setOrganizer:_organizer]): now accepts a nil argument.
+
+	* CardGroup.m ([CardGroup -children]): now returns an NSMutableArray.
+	([CardGroup -copyWithZone:aZone])
+	([CardGroup -mutableCopyWithZone:aZone]): the children were not
+	properlty cloned, we thus clone them explicitly.
+
 2008-07-16  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
 
 	* iCalDateTime.m ([iCalDateTime -setDate:dateTime]): don't set
diff --git a/SOPE/NGCards/iCalEntityObject.m b/SOPE/NGCards/iCalEntityObject.m
index 146f2b538..5f6ff9775 100644
--- a/SOPE/NGCards/iCalEntityObject.m
+++ b/SOPE/NGCards/iCalEntityObject.m
@@ -277,8 +277,13 @@
 
 - (void) setOrganizer: (iCalPerson *) _organizer
 {
-  [_organizer setTag: @"organizer"];
-  [self setUniqueChild: _organizer];
+  if (_organizer)
+    {
+      [_organizer setTag: @"organizer"];
+      [self setUniqueChild: _organizer];
+    }
+  else
+    [children removeObjectsInArray: [self childrenWithTag: @"organizer"]];
 }
 
 - (iCalPerson *) organizer
diff --git a/SOPE/NGCards/iCalRecurrenceCalculator.m b/SOPE/NGCards/iCalRecurrenceCalculator.m
index 66a06ec65..a30be6c74 100644
--- a/SOPE/NGCards/iCalRecurrenceCalculator.m
+++ b/SOPE/NGCards/iCalRecurrenceCalculator.m
@@ -188,17 +188,19 @@ static Class yearlyCalcClass  = Nil;
   NSEnumerator *dates;
   NSCalendarDate *currentDate;
   NGCalendarDateRange *currentRange;
-  int count, maxRanges;
+  unsigned int count, maxRanges;
 
-  maxRanges = [ranges count];
   dates = [[self _dates: exdates withinRange: limits] objectEnumerator];
   while ((currentDate = [dates nextObject]))
-    for (count = (maxRanges - 1); count > -1; count--)
-      {
-	currentRange = [ranges objectAtIndex: count];
-	if ([currentRange containsDate: currentDate])
-	  [ranges removeObjectAtIndex: count];
-      }
+    {
+      maxRanges = [ranges count];
+      for (count = maxRanges; count > 0; count--)
+	{
+	  currentRange = [ranges objectAtIndex: count - 1];
+	  if ([currentRange containsDate: currentDate])
+	    [ranges removeObjectAtIndex: count - 1];
+	}
+    }
 }
 
 + (NSArray *)
diff --git a/SOPE/NGCards/iCalRepeatableEntityObject.h b/SOPE/NGCards/iCalRepeatableEntityObject.h
index fa475a01c..d89cd03ed 100644
--- a/SOPE/NGCards/iCalRepeatableEntityObject.h
+++ b/SOPE/NGCards/iCalRepeatableEntityObject.h
@@ -32,7 +32,7 @@
  are VEVENT, VTODO and VJOURNAL.
 */
 
-@class NSMutableArray, NGCalendarDateRange;
+@class NSCalendarDate, NSMutableArray, NGCalendarDateRange;
 
 @interface iCalRepeatableEntityObject : iCalEntityObject
 // {
@@ -53,7 +53,7 @@
 - (NSArray *)exceptionRules;
 
 - (void)removeAllExceptionDates;
-- (void)addToExceptionDates:(id)_date;
+- (void)addToExceptionDates:(NSCalendarDate *)_date;
 - (BOOL)hasExceptionDates;
 - (NSArray *)exceptionDates;
 
diff --git a/SOPE/NGCards/iCalRepeatableEntityObject.m b/SOPE/NGCards/iCalRepeatableEntityObject.m
index dc52aa950..26214f5a6 100644
--- a/SOPE/NGCards/iCalRepeatableEntityObject.m
+++ b/SOPE/NGCards/iCalRepeatableEntityObject.m
@@ -107,9 +107,15 @@
   [children removeObjectsInArray: [self childrenWithTag: @"exdate"]];
 }
 
-- (void) addToExceptionDates: (id) _rdate
+- (void) addToExceptionDates: (NSCalendarDate *) _rdate
 {
-  [self addChild: _rdate];
+  iCalDateTime *dateTime;
+
+  dateTime = [iCalDateTime new];
+  [dateTime setTag: @"exdate"];
+  [dateTime setDateTime: _rdate];
+  [self addChild: dateTime];
+  [dateTime release];
 }
 
 - (void) setExceptionDates: (NSArray *) _rdates