--- calendar/includes/calendar.inc.original	2010-01-30 00:30:13.000000000 +0000
+++ calendar/includes/calendar.inc	2010-01-30 01:07:30.000000000 +0000
@@ -354,6 +354,7 @@
     // duplicate items from the other date fields, so add a way to
     // make sure each individual date field only gets added to the
     // calendar one time.
+    $base_field_hack = ($view->base_field == 'nid');
     $processed = array();
     $rrule_processed = array();
     foreach ($items as $pos => $item) {
@@ -363,7 +364,8 @@
         $real_field = str_replace(array('_value2', '_value'), '', $field_name);
       }
       
-      $id = 'calendar:'. $item->{$view->base_field} .':'. $real_field .':'. $delta;
+      // $id = 'calendar:'. $item->{$view->base_field} .':'. $real_field .':'. $delta;
+      $id = 'calendar:'. ($base_field_hack ? $item->raw->nid : '') .':'. $item->{$view->base_field} .':'. $real_field .':'. $delta;
       
       // When creating iCal feeds for repeating dates we don't want all
       // the multiple values, send only the first value.