diff --git a/akonadi/tests/itemserializertest.cpp b/akonadi/tests/itemserializertest.cpp
index f75b6c7c3..f5f9af939 100644
--- a/akonadi/tests/itemserializertest.cpp
+++ b/akonadi/tests/itemserializertest.cpp
@@ -1,66 +1,69 @@
 /*
     Copyright (c) 2007 Volker Krause <vkrause@kde.org>
 
     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Library General Public License as published by
     the Free Software Foundation; either version 2 of the License, or (at your
     option) any later version.
 
     This library is distributed in the hope that it will be useful, but WITHOUT
     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
     License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to the
     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301, USA.
 */
 
 #include "itemserializertest.h"
 
 #include <akonadi/attributefactory.h>
 #include <akonadi/item.h>
 #include <akonadi/itemserializer.h>
 
 #include <qtest_kde.h>
 
 using namespace Akonadi;
 
 QTEST_KDEMAIN( ItemSerializerTest, NoGUI )
 
 void ItemSerializerTest::testEmptyPayload()
 {
   // should not crash
   QByteArray data;
   Item item;
   ItemSerializer::deserialize( item, Item::FullPayload, data, 0 );
   QVERIFY( data.isEmpty() );
 }
 
 void ItemSerializerTest::testDefaultSerializer_data()
 {
   QTest::addColumn<QByteArray>( "serialized" );
 
-  QTest::newRow( "empty" ) << QByteArray();
-  QTest::newRow( "null" ) << QByteArray( "\0" );
-  QTest::newRow( "mixed" ) << QByteArray( "\0\r\n\0bla" );
+  QTest::newRow( "null" ) << QByteArray();
+  QTest::newRow( "empty" ) << QByteArray( "" );
+  QTest::newRow( "nullbytei" ) << QByteArray( "\0", 1 );
+  QTest::newRow( "mixed" ) << QByteArray( "\0\r\n\0bla", 7 );
 }
 
 void ItemSerializerTest::testDefaultSerializer()
 {
   QFETCH( QByteArray, serialized );
   Item item;
   item.setMimeType( "application/octet-stream" );
   ItemSerializer::deserialize( item, Item::FullPayload, serialized, 0 );
 
   QVERIFY( item.hasPayload<QByteArray>() );
   QCOMPARE( item.payload<QByteArray>(), serialized );
 
   QByteArray data;
   int version = 0;
   ItemSerializer::serialize( item, Item::FullPayload, data, version );
-  QCOMPARE( serialized, data );
+  QCOMPARE( data, serialized );
+  QEXPECT_FAIL( "null", "Serializer cannot distinguish null vs. empty", Continue );
+  QCOMPARE( data.isNull(), serialized.isNull() );
 }
 
 #include "itemserializertest.moc"
diff --git a/akonadi/tests/itemstoretest.cpp b/akonadi/tests/itemstoretest.cpp
index b5e079122..bc049a9e7 100644
--- a/akonadi/tests/itemstoretest.cpp
+++ b/akonadi/tests/itemstoretest.cpp
@@ -1,347 +1,350 @@
   /*
     Copyright (c) 2006 Volker Krause <vkrause@kde.org>
     Copyright (c) 2007 Robert Zwerus <arzie@dds.nl>
 
     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Library General Public License as published by
     the Free Software Foundation; either version 2 of the License, or (at your
     option) any later version.
 
     This library is distributed in the hope that it will be useful, but WITHOUT
     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
     License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to the
     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301, USA.
 */
 
 #include "control.h"
 #include "itemstoretest.h"
 #include "testattribute.h"
 #include <akonadi/agentmanager.h>
 #include <akonadi/agentinstance.h>
 #include <akonadi/attributefactory.h>
 #include <akonadi/collectionfetchjob.h>
 #include <akonadi/collectionselectjob.h>
 #include <akonadi/itemcreatejob.h>
 #include <akonadi/itemdeletejob.h>
 #include <akonadi/itemfetchjob.h>
 #include <akonadi/itemfetchscope.h>
 #include <akonadi/itemmodifyjob.h>
 #include <qtest_akonadi.h>
 #include "test_utils.h"
 
 using namespace Akonadi;
 
 QTEST_AKONADIMAIN( ItemStoreTest, NoGUI )
 
 static Collection res1_foo;
 static Collection res2;
 static Collection res3;
 
 void ItemStoreTest::initTestCase()
 {
   Control::start();
   AttributeFactory::registerAttribute<TestAttribute>();
 
   // get the collections we run the tests on
   res1_foo = Collection( collectionIdFromPath( "res1/foo" ) );
   QVERIFY( res1_foo.isValid() );
   res2 = Collection( collectionIdFromPath( "res2" ) );
   QVERIFY( res2.isValid() );
   res3 = Collection( collectionIdFromPath( "res3" ) );
   QVERIFY( res3.isValid() );
 
   // switch all resources offline to reduce interference from them
   foreach ( Akonadi::AgentInstance agent, Akonadi::AgentManager::self()->instances() )
     agent.setIsOnline( false );
 }
 
 void ItemStoreTest::testFlagChange()
 {
   ItemFetchJob *fjob = new ItemFetchJob( Item( 1 ) );
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   Item item = fjob->items()[0];
 
   // add a flag
   Item::Flags origFlags = item.flags();
   Item::Flags expectedFlags = origFlags;
   expectedFlags.insert( "added_test_flag_1" );
   item.setFlag( "added_test_flag_1" );
   ItemModifyJob *sjob = new ItemModifyJob( item, this );
   QVERIFY( sjob->exec() );
 
   fjob = new ItemFetchJob( Item( 1 ) );
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QCOMPARE( item.flags().count(), expectedFlags.count() );
   Item::Flags diff = expectedFlags - item.flags();
   QVERIFY( diff.isEmpty() );
 
   // set flags
   expectedFlags.insert( "added_test_flag_2" );
   item.setFlags( expectedFlags );
   sjob = new ItemModifyJob( item, this );
   QVERIFY( sjob->exec() );
 
   fjob = new ItemFetchJob( Item( 1 ) );
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QCOMPARE( item.flags().count(), expectedFlags.count() );
   diff = expectedFlags - item.flags();
   QVERIFY( diff.isEmpty() );
 
   // remove a flag
   item.clearFlag( "added_test_flag_1" );
   item.clearFlag( "added_test_flag_2" );
   sjob = new ItemModifyJob( item, this );
   QVERIFY( sjob->exec() );
 
   fjob = new ItemFetchJob( Item( 1 ) );
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QCOMPARE( item.flags().count(), origFlags.count() );
   diff = origFlags - item.flags();
   QVERIFY( diff.isEmpty() );
 }
 
 void ItemStoreTest::testDataChange_data()
 {
   QTest::addColumn<QByteArray>( "data" );
 
-  QTest::newRow( "empty" ) << QByteArray();
-  QTest::newRow( "nullbyte" ) << QByteArray("\0" );
-  QTest::newRow( "nullbyte2" ) << QByteArray( "\0X" );
+  QTest::newRow( "simple" ) << QByteArray( "testbody" );
+  QTest::newRow( "null" ) << QByteArray();
+  QTest::newRow( "empty" ) << QByteArray( "" );
+  QTest::newRow( "nullbyte" ) << QByteArray( "\0", 1 );
+  QTest::newRow( "nullbyte2" ) << QByteArray( "\0X", 2 );
   QTest::newRow( "linebreaks" ) << QByteArray( "line1\nline2\n\rline3\rline4\r\n" );
   QTest::newRow( "linebreaks2" ) << QByteArray( "line1\r\nline2\r\n\r\n" );
   QTest::newRow( "linebreaks3" ) << QByteArray( "line1\nline2" );
-  QTest::newRow( "simple" ) << QByteArray( "testbody" );
   QByteArray b;
   QTest::newRow( "big" ) << b.fill( 'a', 1 << 20 );
   QTest::newRow( "bignull" ) << b.fill( '\0', 1 << 20 );
   QTest::newRow( "bigcr" ) << b.fill( '\r', 1 << 20 );
   QTest::newRow( "biglf" ) << b.fill( '\n', 1 << 20 );
 }
 
 void ItemStoreTest::testDataChange()
 {
   QFETCH( QByteArray, data );
 
   Item item;
   ItemFetchJob *prefetchjob = new ItemFetchJob( Item( 1 ) );
   prefetchjob->exec();
   item = prefetchjob->items()[0];
   item.setMimeType( "application/octet-stream" );
   item.setPayload( data );
   QCOMPARE( item.payload<QByteArray>(), data );
 
   // modify data
   ItemModifyJob *sjob = new ItemModifyJob( item );
   QVERIFY( sjob->exec() );
 
   ItemFetchJob *fjob = new ItemFetchJob( Item( 1 ) );
   fjob->fetchScope().fetchFullPayload();
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QVERIFY( item.hasPayload<QByteArray>() );
   QCOMPARE( item.payload<QByteArray>(), data );
+  QEXPECT_FAIL( "null", "Serializer cannot distinguish null vs. empty", Continue );
+  QCOMPARE( item.payload<QByteArray>().isNull(), data.isNull() );
 }
 
 void ItemStoreTest::testRemoteId_data()
 {
   QTest::addColumn<QString>( "rid" );
   QTest::addColumn<QString>( "exprid" );
 
   QTest::newRow( "set" ) << QString( "A" ) << QString( "A" );
   QTest::newRow( "no-change" ) << QString() << QString( "A" );
   QTest::newRow( "clear" ) << QString( "" ) << QString( "" );
   QTest::newRow( "reset" ) << QString( "A" ) << QString( "A" );
 }
 
 void ItemStoreTest::testRemoteId()
 {
   QFETCH( QString, rid );
   QFETCH( QString, exprid );
 
   ItemFetchJob *prefetchjob = new ItemFetchJob( Item( 1 ) );
   prefetchjob->exec();
   Item item = prefetchjob->items()[0];
 
   item.setId( 1 );
   item.setRemoteId( rid );
   ItemModifyJob *store = new ItemModifyJob( item, this );
   QVERIFY( store->exec() );
 
   ItemFetchJob *fetch = new ItemFetchJob( item, this );
   QVERIFY( fetch->exec() );
   QCOMPARE( fetch->items().count(), 1 );
   item = fetch->items().at( 0 );
   QCOMPARE( item.remoteId(), exprid );
 }
 
 void ItemStoreTest::testMultiPart()
 {
   ItemFetchJob *prefetchjob = new ItemFetchJob( Item( 1 ) );
   QVERIFY( prefetchjob->exec() );
   QCOMPARE( prefetchjob->items().count(), 1 );
   Item item = prefetchjob->items()[0];
   item.setMimeType( "application/octet-stream" );
   item.setPayload<QByteArray>( "testmailbody" );
   item.attribute<TestAttribute>( Item::AddIfMissing )->data = "extra";
 
   // store item
   ItemModifyJob *sjob = new ItemModifyJob( item );
   QVERIFY( sjob->exec() );
 
   ItemFetchJob *fjob = new ItemFetchJob( Item( 1 ) );
   fjob->fetchScope().fetchAttribute<TestAttribute>();
   fjob->fetchScope().fetchFullPayload();
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QVERIFY( item.hasPayload<QByteArray>() );
   QCOMPARE( item.payload<QByteArray>(), QByteArray("testmailbody") );
   QVERIFY( item.hasAttribute<TestAttribute>() );
   QCOMPARE( item.attribute<TestAttribute>()->data, QByteArray("extra") );
 
   // clean up
   item.removeAttribute( "EXTRA" );
   sjob = new ItemModifyJob( item );
   QVERIFY( sjob->exec() );
 }
 
 void ItemStoreTest::testPartRemove()
 {
   ItemFetchJob *prefetchjob = new ItemFetchJob( Item( 2 ) );
   prefetchjob->exec();
   Item item = prefetchjob->items()[0];
   item.setMimeType( "application/octet-stream" );
   item.attribute<TestAttribute>( Item::AddIfMissing )->data = "extra";
 
   // store item
   ItemModifyJob *sjob = new ItemModifyJob( item );
   QVERIFY( sjob->exec() );
 
   // fetch item and its parts (should be RFC822, HEAD and EXTRA)
   ItemFetchJob *fjob = new ItemFetchJob( Item( 2 ) );
   fjob->fetchScope().fetchFullPayload();
   fjob->fetchScope().fetchAllAttributes();
   QVERIFY( fjob->exec() );
   QCOMPARE( fjob->items().count(), 1 );
   item = fjob->items()[0];
   QCOMPARE( item.attributes().count(), 2 );
   QVERIFY( item.hasAttribute<TestAttribute>() );
 
   // remove a part
   item.removeAttribute<TestAttribute>();
   sjob = new ItemModifyJob( item );
   QVERIFY( sjob->exec() );
 
   // fetch item again (should only have RFC822 and HEAD left)
   ItemFetchJob *fjob2 = new ItemFetchJob( Item( 2 ) );
   fjob2->fetchScope().fetchFullPayload();
   fjob2->fetchScope().fetchAllAttributes();
   QVERIFY( fjob2->exec() );
   QCOMPARE( fjob2->items().count(), 1 );
   item = fjob2->items()[0];
   QCOMPARE( item.attributes().count(), 1 );
   QVERIFY( !item.hasAttribute<TestAttribute>() );
 }
 
 void ItemStoreTest::testRevisionCheck()
 {
   // make sure we don't have any other collection selected
   // otherwise EXPUNGE doesn't work and will be triggered by
   // the following tests and mess up the monitor testing
   CollectionSelectJob *sel = new CollectionSelectJob( Collection::root(), this );
   QVERIFY( sel->exec() );
 
   // fetch same item twice
   Item ref( 2 );
   ItemFetchJob *prefetchjob = new ItemFetchJob( ref );
   QVERIFY( prefetchjob->exec() );
   QCOMPARE( prefetchjob->items().count(), 1 );
   Item item1 = prefetchjob->items()[0];
   Item item2 = prefetchjob->items()[0];
 
   // store first item unmodified
   ItemModifyJob *sjob = new ItemModifyJob( item1 );
   QVERIFY( sjob->exec() );
 
   // try to store second item
   ItemModifyJob *sjob2 = new ItemModifyJob( item2 );
   item2.attribute<TestAttribute>( Item::AddIfMissing )->data = "extra";
   QVERIFY( !sjob2->exec() );
 
   // fetch same again
   prefetchjob = new ItemFetchJob( ref );
   prefetchjob->exec();
   item1 = prefetchjob->items()[0];
 
   // delete item
   ItemDeleteJob *djob = new ItemDeleteJob( ref, this );
   djob->exec();
 
   // try to store it
   sjob = new ItemModifyJob( item1 );
   QVERIFY( !sjob->exec() );
 }
 
 void ItemStoreTest::testModificationTime()
 {
   Item item;
   item.setMimeType( "text/directory" );
   QVERIFY( item.modificationTime().isNull() );
 
   ItemCreateJob *job = new ItemCreateJob( item, res1_foo );
   QVERIFY( job->exec() );
 
   // The item should have a datetime set now.
   item = job->item();
   QVERIFY( !item.modificationTime().isNull() );
   QDateTime initialDateTime = item.modificationTime();
 
   // Fetch the same item again.
   Item item2( item.id() );
   ItemFetchJob *fjob = new ItemFetchJob( item2, this );
   QVERIFY( fjob->exec() );
   item2 = fjob->items().first();
   QCOMPARE( initialDateTime, item2.modificationTime() );
 
   // Lets wait 5 secs.
   QTest::qWait( 5000 );
 
   // Modify the item
   item.attribute<TestAttribute>( Item::AddIfMissing )->data = "extra";
   ItemModifyJob *mjob = new ItemModifyJob( item );
   QVERIFY( mjob->exec() );
 
   // The item should still have a datetime set and that date should be somewhere
   // after the initialDateTime.
   item = mjob->item();
   QVERIFY( !item.modificationTime().isNull() );
   QVERIFY( initialDateTime < item.modificationTime() );
 
   // Fetch the item after modification.
   Item item3( item.id() );
   ItemFetchJob *fjob2 = new ItemFetchJob( item3, this );
   QVERIFY( fjob2->exec() );
 
   // item3 should have the same modification time as item.
   item3 = fjob2->items().first();
   QCOMPARE( item3.modificationTime(), item.modificationTime() );
 
   // Clean up
   ItemDeleteJob *idjob = new ItemDeleteJob( item, this );
   QVERIFY( idjob->exec() );
 }
 
 #include "itemstoretest.moc"