diff --git a/ChangeLog b/ChangeLog
index 61fc3d51a..504f620cc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,62 @@
+2012-03-16  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
+
+	* OpenChange/MAPIStoreGCSFolder.m
+	(-predecessorChangeListForMessageWithKey:): same as below.
+	(-setChangeKey:forMessageWithKey:): synchronise the version cache
+	if the message entry is not found.
+	(-updateVersionsForMessageWithKey:withChangeKey:): new method,
+	common to all GCS messages, that updates the folder cache and
+	insert the PidTagChangeKey provided by the client during the save
+	operations.
+
+	* OpenChange/MAPIStoreMailFolder.m
+	(-predecessorChangeListForMessageWithKey:): the returned list must
+	be binary ordered by GUID (as specified in the SPEC). We now do so
+	using the new function below.
+	(-getPidTagMessageClass:inMemCtx:): removed method, as folders are
+	not supposed to return a PidTagMessageClass attribute.
+
+	* OpenChange/MAPIStoreTypes.m (MAPICNCompare): added as void *
+	parameter so that the function can be used as a comparator
+	function in NSArray sort methods.
+	(MAPIChangeKeyGUIDCompare): new comparator function to compare the
+	GUID of two change key streams.
+
+	* OpenChange/MAPIStoreGCSMessage.m (-updateVersions): new proxy
+	method for -[MAPIStoreGCSFolder
+	updateVersionsForMessageWithKey:withChangeKey:].
+
+	* OpenChange/MAPIStoreGCSBaseContext.m
+	(+createRootSecondaryFolderWithFID:andName:forUser:): setup the
+	userContext in the MAPIApp object.
+
+	* OpenChange/MAPIStoreMailContext.m
+	(+createRootSecondaryFolderWithFID:andName:forUser:): setup the
+	userContext in the MAPIApp object.
+
+	* OpenChange/MAPIStoreContactsFolder.m
+	(-getPidTagDefaultPostMessageClass:inMemCtx:): new getter.
+
+	* OpenChange/MAPIStoreCalendarFolder.m
+	(-getPidTagDefaultPostMessageClass:inMemCtx:): new getter.
+
+	* OpenChange/MAPIStoreTasksFolder.m
+	(-getPidTagDefaultPostMessageClass:inMemCtx:): new getter.
+
+	* OpenChange/MAPIStoreFolder.m
+	(-getPidTagDefaultPostMessageClass:inMemCtx:): new getter.
+
+	* OpenChange/MAPIStoreMessage.m
+	(-getPidTagMessageStatus:inMemCtx:): removed useless getter.
+
+	* OpenChange/MAPIStoreSOGo.m (sogo_backend_init): check for
+	"SOGoDebugLeaks" in the user defaults and activate GSDebug
+	allocation utilities.
+
+	* OpenChange/NSData+MAPIStore.m (+dataWithChangeKeyGUID:andCnt:):
+	new method replacing _dataFromChangeKeyGUID:andCnt: from
+	MAPIStore{GCS,Mail}Folder.
+
 2012-03-16  Jean Raby  <jraby@inverse.ca>
 
 	* sogo.spec debian/sogo.postint: upon installation, update timestamp
diff --git a/OpenChange/MAPIStoreCalendarFolder.m b/OpenChange/MAPIStoreCalendarFolder.m
index f50b0358c..71dcddb4e 100644
--- a/OpenChange/MAPIStoreCalendarFolder.m
+++ b/OpenChange/MAPIStoreCalendarFolder.m
@@ -172,5 +172,4 @@
   return MAPISTORE_SUCCESS;
 }
 
-
 @end
diff --git a/OpenChange/MAPIStoreCalendarMessage.m b/OpenChange/MAPIStoreCalendarMessage.m
index bd299eb35..3c657b47d 100644
--- a/OpenChange/MAPIStoreCalendarMessage.m
+++ b/OpenChange/MAPIStoreCalendarMessage.m
@@ -1064,12 +1064,7 @@
   if (newParticipationStatus)
     [sogoObject changeParticipationStatus: newParticipationStatus
                              withDelegate: nil];
-
-  [(MAPIStoreCalendarFolder *) container synchroniseCache];
-  value = [properties objectForKey: MAPIPropertyKey (PR_CHANGE_KEY)];
-  if (value)
-    [(MAPIStoreCalendarFolder *) container
-    setChangeKey: value forMessageWithKey: [self nameInContainer]];
+  [self updateVersions];
 }
 
 - (id) lookupAttachment: (NSString *) childKey
diff --git a/OpenChange/MAPIStoreContactsFolder.m b/OpenChange/MAPIStoreContactsFolder.m
index 49c26df90..3e7fe71c5 100644
--- a/OpenChange/MAPIStoreContactsFolder.m
+++ b/OpenChange/MAPIStoreContactsFolder.m
@@ -31,11 +31,13 @@
 #import "MAPIStoreContactsContext.h"
 #import "MAPIStoreContactsMessage.h"
 #import "MAPIStoreContactsMessageTable.h"
+#import "NSString+MAPIStore.h"
 
 #import "MAPIStoreContactsFolder.h"
 
 #include <util/time.h>
 #include <gen_ndr/exchange.h>
+#include <mapistore/mapistore_errors.h>
 
 @implementation MAPIStoreContactsFolder
 
@@ -112,4 +114,12 @@
   return [[self activeUserRoles] containsObject: SOGoRole_ObjectViewer];
 }
 
+- (int) getPidTagDefaultPostMessageClass: (void **) data
+                                inMemCtx: (TALLOC_CTX *) memCtx
+{
+  *data = [@"IPM.Contact" asUnicodeInMemCtx: memCtx];
+
+  return MAPISTORE_SUCCESS;
+}
+
 @end
diff --git a/OpenChange/MAPIStoreContactsMessage.m b/OpenChange/MAPIStoreContactsMessage.m
index d1bdebadc..c8af5c05b 100644
--- a/OpenChange/MAPIStoreContactsMessage.m
+++ b/OpenChange/MAPIStoreContactsMessage.m
@@ -1157,11 +1157,8 @@ fromProperties: (NSDictionary *) attachmentProps
   // we save the new/modified card
   //
   [sogoObject saveContentString: [newCard versitString]];
-  [(MAPIStoreContactsFolder *) container synchroniseCache];
-  value = [properties objectForKey: MAPIPropertyKey (PR_CHANGE_KEY)];
-  if (value)
-    [(MAPIStoreContactsFolder *) container
-    setChangeKey: value forMessageWithKey: [self nameInContainer]];
+
+  [self updateVersions];
 }
 
 @end
diff --git a/OpenChange/MAPIStoreFolder.m b/OpenChange/MAPIStoreFolder.m
index 9565288fe..c6702c76c 100644
--- a/OpenChange/MAPIStoreFolder.m
+++ b/OpenChange/MAPIStoreFolder.m
@@ -1278,6 +1278,14 @@ Class NSExceptionK, MAPIStoreFAIMessageK, MAPIStoreMessageTableK, MAPIStoreFAIMe
   return rc;
 }
 
+- (int) getPidTagDefaultPostMessageClass: (void **) data
+                                inMemCtx: (TALLOC_CTX *) memCtx
+{
+  *data = [@"IPM.Note" asUnicodeInMemCtx: memCtx];
+
+  return MAPISTORE_SUCCESS;
+}
+
 - (int) getProperty: (void **) data
             withTag: (enum MAPITAGS) propTag
            inMemCtx: (TALLOC_CTX *) memCtx
diff --git a/OpenChange/MAPIStoreGCSBaseContext.m b/OpenChange/MAPIStoreGCSBaseContext.m
index d13e6bc58..296479251 100644
--- a/OpenChange/MAPIStoreGCSBaseContext.m
+++ b/OpenChange/MAPIStoreGCSBaseContext.m
@@ -27,6 +27,7 @@
 #import <SOGo/SOGoGCSFolder.h>
 #import <SOGo/SOGoParentFolder.h>
 
+#import "MAPIApplication.h"
 #import "MAPIStoreUserContext.h"
 #import "NSString+MAPIStore.h"
 
@@ -118,6 +119,7 @@
 
   userContext = [MAPIStoreUserContext userContextWithUsername: userName
                                                andTDBIndexing: NULL];
+  [MAPIApp setUserContext: userContext];
   moduleName = [self MAPIModuleName];
   parentFolder = [[userContext rootFolders] objectForKey: moduleName];
   if (![parentFolder newFolderWithName: folderName
@@ -126,6 +128,7 @@
                              userName, moduleName, nameInContainer];
   else
     mapistoreURI = nil;
+  [MAPIApp setUserContext: nil];
 
   return mapistoreURI;
 }
diff --git a/OpenChange/MAPIStoreGCSFolder.h b/OpenChange/MAPIStoreGCSFolder.h
index d87c9c63c..0d0c1e6df 100644
--- a/OpenChange/MAPIStoreGCSFolder.h
+++ b/OpenChange/MAPIStoreGCSFolder.h
@@ -41,6 +41,8 @@
 
 /* synchronisation */
 - (BOOL) synchroniseCache;
+- (void) updateVersionsForMessageWithKey: (NSString *) messageKey
+                           withChangeKey: (NSData *) newChangeKey;
 - (NSNumber *) lastModifiedFromMessageChangeNumber: (NSNumber *) changeNum;
 - (NSNumber *) changeNumberForMessageWithKey: (NSString *) messageKey;
 
diff --git a/OpenChange/MAPIStoreGCSFolder.m b/OpenChange/MAPIStoreGCSFolder.m
index b27e0a24f..e5f6bbd65 100644
--- a/OpenChange/MAPIStoreGCSFolder.m
+++ b/OpenChange/MAPIStoreGCSFolder.m
@@ -252,7 +252,7 @@ static Class NSNumberK;
     ...
   };
   VersionMapping = {
-    Version = MessageKey;
+    Version = last-modified;
     ...
   }
 }
@@ -458,6 +458,15 @@ static Class NSNumberK;
 
   return rc;
 }
+
+- (void) updateVersionsForMessageWithKey: (NSString *) messageKey
+                           withChangeKey: (NSData *) newChangeKey
+{
+  [self synchroniseCache];
+
+  if (newChangeKey)
+    [self setChangeKey: newChangeKey forMessageWithKey: messageKey];
+}
  
 - (NSNumber *) lastModifiedFromMessageChangeNumber: (NSNumber *) changeNum
 {
@@ -491,27 +500,17 @@ static Class NSNumberK;
   messages = [[versionsMessage properties] objectForKey: @"Messages"];
   messageEntry = [messages objectForKey: messageKey];
   if (!messageEntry)
-    abort ();
+    {
+      [self synchroniseCache];
+      messageEntry = [messages objectForKey: messageKey];
+      if (!messageEntry)
+        abort ();
+    }
   [self _setChangeKey: changeKey forMessageEntry: messageEntry];
   
   [versionsMessage save];
 }
 
-- (NSData *) _dataFromChangeKeyGUID: (NSString *) guidString
-                             andCnt: (NSData *) globCnt
-{
-  NSMutableData *changeKey;
-  struct GUID guid;
-
-  changeKey = [NSMutableData dataWithCapacity: 16 + [globCnt length]];
-
-  [guidString extractGUID: &guid];
-  [changeKey appendData: [NSData dataWithGUID: &guid]];
-  [changeKey appendData: globCnt];
-
-  return changeKey;
-}
-
 - (NSData *) changeKeyForMessageWithKey: (NSString *) messageKey
 {
   NSDictionary *messages, *changeKeyDict;
@@ -525,7 +524,7 @@ static Class NSNumberK;
     {
       guid = [changeKeyDict objectForKey: @"GUID"];
       globCnt = [changeKeyDict objectForKey: @"LocalId"];
-      changeKey = [self _dataFromChangeKeyGUID: guid andCnt: globCnt];
+      changeKey = [NSData dataWithChangeKeyGUID: guid andCnt: globCnt];
     }
 
   return changeKey;
@@ -533,9 +532,10 @@ static Class NSNumberK;
 
 - (NSData *) predecessorChangeListForMessageWithKey: (NSString *) messageKey
 {
-  NSMutableData *changeKeys = nil;
+  NSMutableData *list = nil;
   NSDictionary *messages, *changeListDict;
   NSArray *keys;
+  NSMutableArray *changeKeys;
   NSUInteger count, max;
   NSData *changeKey;
   NSString *guid;
@@ -546,21 +546,30 @@ static Class NSNumberK;
                      objectForKey: @"PredecessorChangeList"];
   if (changeListDict)
     {
-      changeKeys = [NSMutableData data];
       keys = [changeListDict allKeys];
       max = [keys count];
 
+      changeKeys = [NSMutableArray arrayWithCapacity: max];
       for (count = 0; count < max; count++)
         {
           guid = [keys objectAtIndex: count];
           globCnt = [changeListDict objectForKey: guid];
-          changeKey = [self _dataFromChangeKeyGUID: guid andCnt: globCnt];
-          [changeKeys appendUInt8: [changeKey length]];
-          [changeKeys appendData: changeKey];
+          changeKey = [NSData dataWithChangeKeyGUID: guid andCnt: globCnt];
+          [changeKeys addObject: changeKey];
+        }
+      [changeKeys sortUsingFunction: MAPIChangeKeyGUIDCompare
+                            context: nil];
+
+      list = [NSMutableData data];
+      for (count = 0; count < max; count++)
+        {
+          changeKey = [changeKeys objectAtIndex: count];
+          [list appendUInt8: [changeKey length]];
+          [list appendData: changeKey];
         }
     }
 
-  return changeKeys;
+  return list;
 }
 
 - (NSArray *) getDeletedKeysFromChangeNumber: (uint64_t) changeNum
@@ -627,11 +636,11 @@ static Class NSNumberK;
                   currentChangeNum
                     = [[messageEntry objectForKey: @"version"]
                         unsignedLongLongValue];
-                  if (MAPICNCompare (changeNum, currentChangeNum)
+                  if (MAPICNCompare (changeNum, currentChangeNum, NULL)
                       == NSOrderedAscending)
                     {
                       [(NSMutableArray *) deletedKeys addObject: cName];
-                      if (MAPICNCompare (maxChangeNum, currentChangeNum)
+                      if (MAPICNCompare (maxChangeNum, currentChangeNum, NULL)
                           == NSOrderedAscending)
                         maxChangeNum = currentChangeNum;
                     }
diff --git a/OpenChange/MAPIStoreGCSMessage.h b/OpenChange/MAPIStoreGCSMessage.h
index 883923e5f..5ada9290b 100644
--- a/OpenChange/MAPIStoreGCSMessage.h
+++ b/OpenChange/MAPIStoreGCSMessage.h
@@ -29,6 +29,9 @@
 {
 }
 
+/* subclass helpers */
+- (void) updateVersions;
+
 @end
 
 #endif /* MAPISTOREGCSMESSAGE_H */
diff --git a/OpenChange/MAPIStoreGCSMessage.m b/OpenChange/MAPIStoreGCSMessage.m
index 4d7ea0c07..c62f87990 100644
--- a/OpenChange/MAPIStoreGCSMessage.m
+++ b/OpenChange/MAPIStoreGCSMessage.m
@@ -21,6 +21,7 @@
  */
 
 #import <Foundation/NSCalendarDate.h>
+#import <Foundation/NSDictionary.h>
 #import <Foundation/NSValue.h>
 #import <NGObjWeb/SoSecurityManager.h>
 #import <NGExtensions/NSObject+Logs.h>
@@ -204,4 +205,15 @@
   return version;
 }
 
+- (void) updateVersions
+{
+  NSData *newChangeKey;
+
+  newChangeKey = [properties objectForKey: MAPIPropertyKey (PR_CHANGE_KEY)];
+
+  [(MAPIStoreGCSFolder *) container
+    updateVersionsForMessageWithKey: [self nameInContainer]
+                      withChangeKey: newChangeKey];
+}
+
 @end
diff --git a/OpenChange/MAPIStoreMailContext.m b/OpenChange/MAPIStoreMailContext.m
index f42f331c9..d91d76514 100644
--- a/OpenChange/MAPIStoreMailContext.m
+++ b/OpenChange/MAPIStoreMailContext.m
@@ -32,6 +32,7 @@
 #import "NSString+MAPIStore.h"
 
 #import <SOGo/NSString+Utilities.h>
+#import "MAPIApplication.h"
 #import "MAPIStoreMailContext.h"
 
 #include <dlinklist.h>
@@ -176,6 +177,7 @@ MakeDisplayFolderName (NSString *folderName)
 
   userContext = [MAPIStoreUserContext userContextWithUsername: userName
                                                andTDBIndexing: NULL];
+  [MAPIApp setUserContext: userContext];
   accountFolder = [[userContext rootFolders] objectForKey: @"mail"];
   folderName = [NSString stringWithFormat: @"folder%@",
                          [newFolderName asCSSIdentifier]];
@@ -186,6 +188,7 @@ MakeDisplayFolderName (NSString *folderName)
                              userName, userName, folderName];
   else
     mapistoreURI = nil;
+  [MAPIApp setUserContext: nil];
 
   return mapistoreURI;
 }
diff --git a/OpenChange/MAPIStoreMailFolder.m b/OpenChange/MAPIStoreMailFolder.m
index 23c55ec97..f5cfe3340 100644
--- a/OpenChange/MAPIStoreMailFolder.m
+++ b/OpenChange/MAPIStoreMailFolder.m
@@ -218,21 +218,13 @@ static Class SOGoMailFolderK, MAPIStoreOutboxFolderK;
 }
 
 - (int) getPidTagContainerClass: (void **) data
-                   inMemCtx: (TALLOC_CTX *) memCtx
+                       inMemCtx: (TALLOC_CTX *) memCtx
 {
   *data = [@"IPF.Note" asUnicodeInMemCtx: memCtx];
   
   return MAPISTORE_SUCCESS;
 }
 
-- (int) getPidTagMessageClass: (void **) data
-                 inMemCtx: (TALLOC_CTX *) memCtx
-{
-  *data = [@"IPM.Note" asUnicodeInMemCtx: memCtx];
-  
-  return MAPISTORE_SUCCESS;
-}
-
 - (EOQualifier *) nonDeletedQualifier
 {
   static EOQualifier *nonDeletedQualifier = nil;
@@ -686,21 +678,6 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
   [versionsMessage save];
 }
 
-- (NSData *) _dataFromChangeKeyGUID: (NSString *) guidString
-                             andCnt: (NSData *) globCnt
-{
-  NSMutableData *changeKey;
-  struct GUID guid;
-
-  changeKey = [NSMutableData dataWithCapacity: 16 + [globCnt length]];
-
-  [guidString extractGUID: &guid];
-  [changeKey appendData: [NSData dataWithGUID: &guid]];
-  [changeKey appendData: globCnt];
-
-  return changeKey;
-}
-
 - (NSData *) changeKeyForMessageWithKey: (NSString *) messageKey
 {
   NSDictionary *messages, *changeKeyDict;
@@ -716,7 +693,7 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
     {
       guid = [changeKeyDict objectForKey: @"GUID"];
       globCnt = [changeKeyDict objectForKey: @"LocalId"];
-      changeKey = [self _dataFromChangeKeyGUID: guid andCnt: globCnt];
+      changeKey = [NSData dataWithChangeKeyGUID: guid andCnt: globCnt];
     }
 
   return changeKey;
@@ -724,9 +701,10 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
 
 - (NSData *) predecessorChangeListForMessageWithKey: (NSString *) messageKey
 {
-  NSMutableData *changeKeys = nil;
+  NSMutableData *list = nil;
   NSDictionary *messages, *changeListDict;
   NSArray *keys;
+  NSMutableArray *changeKeys;
   NSUInteger count, max;
   NSData *changeKey;
   NSString *guid;
@@ -739,21 +717,30 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
                      objectForKey: @"PredecessorChangeList"];
   if (changeListDict)
     {
-      changeKeys = [NSMutableData data];
       keys = [changeListDict allKeys];
       max = [keys count];
 
+      changeKeys = [NSMutableArray arrayWithCapacity: max];
       for (count = 0; count < max; count++)
         {
           guid = [keys objectAtIndex: count];
           globCnt = [changeListDict objectForKey: guid];
-          changeKey = [self _dataFromChangeKeyGUID: guid andCnt: globCnt];
-          [changeKeys appendUInt8: [changeKey length]];
-          [changeKeys appendData: changeKey];
+          changeKey = [NSData dataWithChangeKeyGUID: guid andCnt: globCnt];
+          [changeKeys addObject: changeKey];
+        }
+      [changeKeys sortUsingFunction: MAPIChangeKeyGUIDCompare
+                            context: nil];
+
+      list = [NSMutableData data];
+      for (count = 0; count < max; count++)
+        {
+          changeKey = [changeKeys objectAtIndex: count];
+          [list appendUInt8: [changeKey length]];
+          [list appendData: changeKey];
         }
     }
 
-  return changeKeys;
+  return list;
 }
 
 - (NSArray *) getDeletedKeysFromChangeNumber: (uint64_t) changeNum
diff --git a/OpenChange/MAPIStoreMessage.m b/OpenChange/MAPIStoreMessage.m
index 2bc1dedaa..35ea1036d 100644
--- a/OpenChange/MAPIStoreMessage.m
+++ b/OpenChange/MAPIStoreMessage.m
@@ -685,12 +685,6 @@ rtf2html (NSData *compressedRTF)
   return MAPISTORE_SUCCESS;
 }
 
-- (int) getPidTagMessageStatus: (void **) data // TODO
-                      inMemCtx: (TALLOC_CTX *) memCtx
-{
-  return [self getLongZero: data inMemCtx: memCtx];
-}
-
 - (int) getPidTagImportance: (void **) data // TODO -> subclass?
                    inMemCtx: (TALLOC_CTX *) memCtx
 {
diff --git a/OpenChange/MAPIStoreNotesFolder.m b/OpenChange/MAPIStoreNotesFolder.m
index aafa79f51..bac783bd2 100644
--- a/OpenChange/MAPIStoreNotesFolder.m
+++ b/OpenChange/MAPIStoreNotesFolder.m
@@ -21,11 +21,21 @@
  */
 
 #import "MAPIStoreNotesFolder.h"
-
 #import "MAPIStoreNotesMessage.h"
+#import "NSString+MAPIStore.h"
+
+#include <mapistore/mapistore_errors.h>
 
 #import "MAPIStoreNotesFolder.h"
 
 @implementation MAPIStoreNotesFolder
 
+- (int) getPidTagDefaultPostMessageClass: (void **) data
+                                inMemCtx: (TALLOC_CTX *) memCtx
+{
+  *data = [@"IPM.StickyNote" asUnicodeInMemCtx: memCtx];
+
+  return MAPISTORE_SUCCESS;
+}
+
 @end
diff --git a/OpenChange/MAPIStoreSOGo.m b/OpenChange/MAPIStoreSOGo.m
index 69df2ffc5..f2b6a807e 100644
--- a/OpenChange/MAPIStoreSOGo.m
+++ b/OpenChange/MAPIStoreSOGo.m
@@ -23,6 +23,7 @@
 /* OpenChange SOGo storage backend */
 
 #import <Foundation/NSAutoreleasePool.h>
+#import <Foundation/NSDebug.h>
 #import <Foundation/NSFileHandle.h>
 #import <Foundation/NSProcessInfo.h>
 #import <Foundation/NSUserDefaults.h>
@@ -48,6 +49,7 @@
 #include <mapistore/mapistore_errors.h>
 
 static Class MAPIStoreContextK = Nil;
+static BOOL leakDebugging = NO;
 
 static enum mapistore_error
 sogo_backend_unexpected_error()
@@ -57,6 +59,16 @@ sogo_backend_unexpected_error()
   return MAPISTORE_SUCCESS;
 }
 
+static void
+sogo_backend_atexit (void)
+{
+  NSAutoreleasePool *pool;
+
+  pool = [NSAutoreleasePool new];
+  NSLog (@"allocated classes:\n%s", GSDebugAllocationList (YES));
+  [pool release];
+}
+
 /**
    \details Initialize sogo mapistore backend
 
@@ -89,6 +101,14 @@ sogo_backend_init (void)
   ud = [NSUserDefaults standardUserDefaults];
   [ud registerDefaults: [ud persistentDomainForName: @"sogod"]];
 
+  if (!leakDebugging && [ud boolForKey: @"SOGoDebugLeaks"])
+    {
+      NSLog (@"  leak debugging on");
+      GSDebugAllocationActive (YES);
+      atexit (sogo_backend_atexit);
+      leakDebugging = YES;
+    }
+
   registry = [SoProductRegistry sharedProductRegistry];
   [registry scanForProductsInDirectory: SOGO_BUNDLES_DIR];
 
diff --git a/OpenChange/MAPIStoreTasksFolder.m b/OpenChange/MAPIStoreTasksFolder.m
index 888daf2a8..bfc0698e8 100644
--- a/OpenChange/MAPIStoreTasksFolder.m
+++ b/OpenChange/MAPIStoreTasksFolder.m
@@ -34,11 +34,13 @@
 #import "MAPIStoreTasksContext.h"
 #import "MAPIStoreTasksMessage.h"
 #import "MAPIStoreTasksMessageTable.h"
+#import "NSString+MAPIStore.h"
 
 #import "MAPIStoreTasksFolder.h"
 
 #include <util/time.h>
 #include <gen_ndr/exchange.h>
+#include <mapistore/mapistore_errors.h>
 
 @implementation MAPIStoreTasksFolder
 
@@ -124,4 +126,12 @@
             [(SOGoAppointmentFolder *) sogoObject aclSQLListingFilter]];
 }
 
+- (int) getPidTagDefaultPostMessageClass: (void **) data
+                                inMemCtx: (TALLOC_CTX *) memCtx
+{
+  *data = [@"IPM.Task" asUnicodeInMemCtx: memCtx];
+
+  return MAPISTORE_SUCCESS;
+}
+
 @end
diff --git a/OpenChange/MAPIStoreTasksMessage.m b/OpenChange/MAPIStoreTasksMessage.m
index 28d690b74..658817650 100644
--- a/OpenChange/MAPIStoreTasksMessage.m
+++ b/OpenChange/MAPIStoreTasksMessage.m
@@ -450,7 +450,7 @@
   // percent complete
   // NOTE: this does not seem to work on Outlook 2003. PidLidPercentComplete's value
   //       is always set to 0, no matter what value is set in Outlook
-  value = [properties objectForKey: MAPIPropertyKey(PidLidPercentComplete)];
+  value = [properties objectForKey: MAPIPropertyKey (PidLidPercentComplete)];
   if (value)
     [vToDo setPercentComplete: [value stringValue]];
 
@@ -462,11 +462,8 @@
   [vToDo setTimeStampAsDate: now];
 
   [sogoObject saveContentString: [vCalendar versitString]];
-  [(MAPIStoreTasksFolder *) container synchroniseCache];
-  value = [properties objectForKey: MAPIPropertyKey (PR_CHANGE_KEY)];
-  if (value)
-    [(MAPIStoreTasksFolder *) container
-    setChangeKey: value forMessageWithKey: [self nameInContainer]];
+
+  [self updateVersions];
 }
 
 @end
diff --git a/OpenChange/MAPIStoreTypes.h b/OpenChange/MAPIStoreTypes.h
index c630b1e15..1fec6a6a7 100644
--- a/OpenChange/MAPIStoreTypes.h
+++ b/OpenChange/MAPIStoreTypes.h
@@ -42,7 +42,8 @@ id NSObjectFromSPropValue (const struct SPropValue *);
 id NSObjectFromMAPISPropValue (const struct mapi_SPropValue *);
 id NSObjectFromValuePointer (enum MAPITAGS, const void *);
 
-NSComparisonResult MAPICNCompare (uint64_t cn1, uint64_t cn2);
+NSComparisonResult MAPICNCompare (uint64_t cn1, uint64_t cn2, void *);
+NSComparisonResult MAPIChangeKeyGUIDCompare (NSData *ck1, NSData *ck2, void *);
 
 static inline NSNumber *
 MAPIPropertyKey (enum MAPITAGS propTag)
diff --git a/OpenChange/MAPIStoreTypes.m b/OpenChange/MAPIStoreTypes.m
index 24dbac860..c294dd429 100644
--- a/OpenChange/MAPIStoreTypes.m
+++ b/OpenChange/MAPIStoreTypes.m
@@ -284,7 +284,7 @@ _reverseCN (uint64_t cn)
 }
 
 NSComparisonResult
-MAPICNCompare (uint64_t cn1, uint64_t cn2)
+MAPICNCompare (uint64_t cn1, uint64_t cn2, void *unused)
 {
   NSComparisonResult result;
 
@@ -298,6 +298,41 @@ MAPICNCompare (uint64_t cn1, uint64_t cn2)
   return result;
 }
 
+NSComparisonResult MAPIChangeKeyGUIDCompare (NSData *ck1, NSData *ck2, void *unused)
+{
+  NSUInteger count;
+  const unsigned char *ptr1, *ptr2;
+  NSComparisonResult result = NSOrderedSame;
+
+  if ([ck1 length] < 16)
+    {
+      NSLog (@"ck1 has a length < 16");
+      abort ();
+    }
+  if ([ck2 length] < 16)
+    {
+      NSLog (@"ck2 has a length < 16");
+      abort ();
+    }
+
+  ptr1 = [ck1 bytes];
+  ptr2 = [ck2 bytes];
+  for (count = 0; result == NSOrderedSame && count < 16; count++)
+    {
+      if (*ptr1 < *ptr2)
+        result = NSOrderedAscending;
+      else if (*ptr1 > *ptr2)
+        result = NSOrderedDescending;
+      else
+        {
+          ptr1++;
+          ptr2++;
+        }
+    }
+
+  return result;
+}
+
 void
 MAPIStoreDumpMessageProperties (NSDictionary *properties)
 {
diff --git a/OpenChange/NSData+MAPIStore.h b/OpenChange/NSData+MAPIStore.h
index fd56f0389..20409c1ac 100644
--- a/OpenChange/NSData+MAPIStore.h
+++ b/OpenChange/NSData+MAPIStore.h
@@ -42,6 +42,9 @@
 + (id) dataWithXID: (const struct XID *) xid;
 - (struct XID *) asXIDInMemCtx: (void *) memCtx;
 
++ (id) dataWithChangeKeyGUID: (NSString *) guidString
+                      andCnt: (NSData *) globCnt;
+
 @end
 
 @interface NSMutableData (MAPIStoreDataTypes)
diff --git a/OpenChange/NSData+MAPIStore.m b/OpenChange/NSData+MAPIStore.m
index e9fe04076..b0143dc1b 100644
--- a/OpenChange/NSData+MAPIStore.m
+++ b/OpenChange/NSData+MAPIStore.m
@@ -20,6 +20,8 @@
  * Boston, MA 02111-1307, USA.
  */
 
+#import "NSString+MAPIStore.h"
+
 #import "NSData+MAPIStore.h"
 
 #undef DEBUG
@@ -168,6 +170,21 @@ static void _fillFlatUIDWithGUID (struct FlatUID_r *flatUID, const struct GUID *
   return xid;
 }
 
++ (id) dataWithChangeKeyGUID: (NSString *) guidString
+                      andCnt: (NSData *) globCnt;
+{
+  NSMutableData *changeKey;
+  struct GUID guid;
+
+  changeKey = [NSMutableData dataWithCapacity: 16 + [globCnt length]];
+
+  [guidString extractGUID: &guid];
+  [changeKey appendData: [NSData dataWithGUID: &guid]];
+  [changeKey appendData: globCnt];
+
+  return changeKey;
+}
+
 @end
 
 @implementation NSMutableData (MAPIStoreDataTypes)
diff --git a/Tests/Integration/test-webdavsync.py b/Tests/Integration/test-webdavsync.py
index d6dc34fca..e28048ddc 100755
--- a/Tests/Integration/test-webdavsync.py
+++ b/Tests/Integration/test-webdavsync.py
@@ -54,7 +54,7 @@ class WebdavSyncTest(unittest.TestCase):
         self.assertTrue(token > 0)
         query1EndTime = int(math.ceil(query1.start + query1.duration))
         self.assertTrue(token <= query1EndTime, 
-                     "token = %d > query1EndTime = %d" % (token, query1EndTime))
+                        "token = %d > query1EndTime = %d" % (token, query1EndTime))
 
         # we make sure that any token is accepted when the collection is
         # empty, but that the returned token differs