diff --git a/kmheaders.cpp b/kmheaders.cpp
index bc407991b..aad602764 100644
--- a/kmheaders.cpp
+++ b/kmheaders.cpp
@@ -1412,48 +1412,59 @@ void KMHeaders::applyFiltersOnMsg()
     int contentX, contentY;
     HeaderItem *nextItem = prepareMove( &contentX, &contentY );
 
-    KMMessageList* msgList = selectedMsgs();
-    if (msgList->isEmpty())
+    //prevent issues with stale message pointers by using serial numbers instead
+    QList<unsigned long> serNums = KMMsgDict::serNumList( *selectedMsgs() );
+    if ( serNums.isEmpty() )
       return;
-    finalizeMove( nextItem, contentX, contentY );
 
+    finalizeMove( nextItem, contentX, contentY );
     CREATE_TIMER(filter);
     START_TIMER(filter);
 
     KCursorSaver busy( KBusyPtr::busy() );
     int msgCount = 0;
-    int msgCountToFilter = msgList->count();
+    int msgCountToFilter = serNums.count();
     ProgressItem* progressItem =
       ProgressManager::createProgressItem (
           "filter"+ProgressManager::getUniqueID(),
           i18n( "Filtering messages" ) );
     progressItem->setTotalItems( msgCountToFilter );
-    QList<KMMsgBase*>::const_iterator it;
-    for ( it = msgList->begin(); it != msgList->end(); it++ ) {
-      KMMsgBase* msgBase = (*it);
-      int diff = msgCountToFilter - ++msgCount;
-      if ( diff < 10 || !( msgCount % 10 ) || msgCount <= 10 ) {
+
+    for ( QList<unsigned long>::ConstIterator it = serNums.constBegin();
+          it != serNums.constEnd(); ++it ) {
+      msgCount++;
+      if ( msgCountToFilter - msgCount < 10 || !( msgCount % 10 ) || msgCount <= 10 ) {
         progressItem->updateProgress();
         QString statusMsg = i18n( "Filtering message %1 of %2",
                                   msgCount, msgCountToFilter );
         KPIM::BroadcastStatus::instance()->setStatusMsg( statusMsg );
         qApp->processEvents( QEventLoop::ExcludeUserInputEvents, 50 );
       }
-      int idx = msgBase->parent()->find(msgBase);
-      assert(idx != -1);
-      KMMessage * msg = msgBase->parent()->getMsg(idx);
-      if (msg->transferInProgress()) continue;
-      msg->setTransferInProgress(true);
-      if ( !msg->isComplete() )
-      {
-	FolderJob *job = mFolder->createJob(msg);
-	connect(job, SIGNAL(messageRetrieved(KMMessage*)),
-		SLOT(slotFilterMsg(KMMessage*)));
-	job->start();
+
+      KMFolder *folder = 0;
+      int idx;
+      KMMsgDict::instance()->getLocation( *it, &folder, &idx );
+      KMMessage *msg = 0;
+      if (folder)
+        msg = folder->getMsg(idx);
+      if (msg) {
+        if (msg->transferInProgress())
+          continue;
+        msg->setTransferInProgress(true);
+        if ( !msg->isComplete() ) {
+          FolderJob *job = mFolder->createJob(msg);
+          connect(job, SIGNAL(messageRetrieved(KMMessage*)),
+                  this, SLOT(slotFilterMsg(KMMessage*)));
+          job->start();
+        } else {
+          if (slotFilterMsg(msg) == 2)
+            break;
+        }
       } else {
-	if (slotFilterMsg(msg) == 2) break;
+        kDebug (5006) << "####### KMHeaders::applyFiltersOnMsg -"
+                          " A message went missing during filtering " << endl;
       }
-      progressItem->incCompletedItems();
+    progressItem->incCompletedItems();
     }
     progressItem->setComplete();
     progressItem = 0;
diff --git a/kmmsgdict.cpp b/kmmsgdict.cpp
index b010d01ce..877e7dc3c 100644
--- a/kmmsgdict.cpp
+++ b/kmmsgdict.cpp
@@ -353,6 +353,20 @@ unsigned long KMMsgDict::getMsgSerNum(KMFolder *folder, int index) const
 
 //-----------------------------------------------------------------------------
 
+//static
+QList<unsigned long> KMMsgDict::serNumList(QList<KMMsgBase *> msgList)
+{
+  QList<unsigned long> ret;
+  for ( unsigned int i = 0; i < msgList.count(); i++ ) {
+    unsigned long serNum = msgList.at(i)->getMsgSerNum();
+    assert( serNum );
+    ret.append( serNum );
+  }
+  return ret;
+}
+
+//-----------------------------------------------------------------------------
+
 QString KMMsgDict::getFolderIdsLocation( const FolderStorage &storage )
 {
   return storage.indexLocation() + ".ids";
diff --git a/kmmsgdict.h b/kmmsgdict.h
index b7f697225..f2c61174f 100644
--- a/kmmsgdict.h
+++ b/kmmsgdict.h
@@ -20,6 +20,8 @@
 #ifndef __KMMSGDICT
 #define __KMMSGDICT
 
+#include <QList>
+
 class KMFolder;
 class KMMsgBase;
 class KMMessage;
@@ -67,6 +69,9 @@ class KMMsgDict
    * @return the message serial number or zero is no such message can be found */
     unsigned long getMsgSerNum( KMFolder *folder, int index ) const;
 
+  /** Convert a list of KMMsgBase pointers to a list of serial numbers */
+    static QList<unsigned long> serNumList(QList<KMMsgBase *> msgList);
+
 private:
  /* FIXME It would be better to do without these, they are the classes
   * involved in filling and maintaining the dict. The MsgList needs access