(fix) make sure to bump LAST-MODIFIED to trigger all auto-scheduling code

ActiveSync/iCalEvent+ActiveSync.m

@@ -891,6 +891,8 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
           [self setAttendees: attendees];
         }
     }
+
+  [self setLastModified: [NSCalendarDate calendarDate]];
 }
 
 - (void) changeParticipationStatus: (NSDictionary *) theValues