? zero_null.patch
Index: plugins/FeedsDataProcessor.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/feeds/plugins/Attic/FeedsDataProcessor.inc,v
retrieving revision 1.23
diff -u -p -r1.23 FeedsDataProcessor.inc
--- plugins/FeedsDataProcessor.inc	10 Sep 2010 15:44:56 -0000	1.23
+++ plugins/FeedsDataProcessor.inc	28 Sep 2010 21:23:54 -0000
@@ -175,7 +175,7 @@ class FeedsDataProcessor extends FeedsPr
    * Set target element, bring element in a FeedsDataHandler format.
    */
   public function setTargetElement(&$target_item, $target_element, $value) {
-    if (empty($value)) {
+    if ($value === NULL) {
       return;
     }
     if (strpos($target_element, '.')) {