Index: akonadi/calendar/scheduler_p.cpp
===================================================================
--- akonadi/calendar/scheduler_p.cpp
+++ akonadi/calendar/scheduler_p.cpp
@@ -275,7 +275,7 @@
                     incidence->setSchedulingID(schedulingUid, existingUid) ;
 
                     if (incidence->hasRecurrenceId()) {
-                        Incidence::Ptr existingInstance = calendar->incidence(incidence->instanceIdentifier());
+                        Incidence::Ptr existingInstance = calendar->incidence(existingUid, incidence->recurrenceId());
                         if (!existingInstance) {
                             // The organizer created an exception, lets create it in our calendar, we don't have it yet
                             const bool success = calendar->addIncidence(incidence);
@@ -312,8 +312,8 @@
         }
     }
 
-    // Move the uid to be the schedulingID and make a unique UID
-    incidence->setSchedulingID(schedulingUid, CalFormat::createUniqueId());
+    // Move the uid to be the schedulingID for make it compatiple with old implemenation
+    incidence->setSchedulingID(schedulingUid);
     // notify the user in case this is an update and we didn't find the to-be-updated incidence
     if (d->mShowDialogs && existingIncidences.isEmpty() && incidence->revision() > 0) {
         KMessageBox::information(
Index: akonadi/calendar/tests/itip_data/invited_us_daily_recid01
===================================================================
--- /dev/null
+++ akonadi/calendar/tests/itip_data/invited_us_daily_recid01
@@ -0,0 +1,21 @@
+BEGIN:VCALENDAR
+PRODID:Zimbra-Calendar-Provider
+VERSION:2.0
+METHOD:REQUEST
+BEGIN:VEVENT
+UID:uosj936i6arrtl9c2i5r2mfuvg
+SUMMARY:exception
+ATTENDEE;RSVP=TRUE;PARTSTAT=ACCEPTED;ROLE=REQ-PARTICIPANT;
+ X-UID=140218344167648:mailto:their-email@dev.nul
+ATTENDEE;RSVP=TRUE:mailto:unittests@dev.nul
+ORGANIZER;mailto:their-email@dev.nul
+DTSTART:20131024T000000Z
+DTEND:20131024T010000Z
+STATUS:CONFIRMED
+CLASS:PUBLIC
+TRANSP:OPAQUE
+RECURRENCE-ID:20131023T090000Z
+DTSTAMP:20131026T004419Z
+DESCRIPTION:some explanation
+END:VEVENT
+END:VCALENDAR
\ No newline at end of file
Index: akonadi/calendar/tests/itiphandlertest.cpp
===================================================================
--- akonadi/calendar/tests/itiphandlertest.cpp
+++ akonadi/calendar/tests/itiphandlertest.cpp
@@ -372,7 +372,7 @@
         KCalCore::Incidence::Ptr incidence = items.first().payload<KCalCore::Incidence::Ptr>();
         QVERIFY(incidence);
         QCOMPARE(incidence->schedulingID(), incidenceUid);
-        QVERIFY(incidence->schedulingID() != incidence->uid());
+        QCOMPARE(incidence->schedulingID(), incidence->uid());
 
         KCalCore::Attendee::Ptr me = ourAttendee(incidence);
         QVERIFY(me);
@@ -457,6 +457,14 @@
     invitation_filenames << QLatin1String("invited_us_daily") << QLatin1String("invited_us_daily_update_recid01");
     QTest::newRow("accept recid update") << invitation_filenames << expected_filename << actions;
     //----------------------------------------------------------------------------------------------
+    // We accept a recurrening event, get an exception accept that too and get an update for the exception afterwards
+    expected_filename = QLatin1String("expected_data/update3");
+    invitation_filenames.clear();
+    invitation_filenames << QLatin1String("invited_us_daily") << QLatin1String("invited_us_daily_recid01") << QLatin1String("invited_us_daily_update_recid01");
+    actions.clear();
+    actions << QLatin1String("accepted") << QLatin1String("accepted") << QLatin1String("accepted");
+    QTest::newRow("accept recid update update") << invitation_filenames << expected_filename << actions;
+    //----------------------------------------------------------------------------------------------
     // We accept a recurring event, then we accept a CANCEL with recuring-id.
     // The result is that a exception with status CANCELLED should be created, and our main incidence
     // should not be touched