diff --git a/plugins/FeedsProcessor.inc b/plugins/FeedsProcessor.inc
index c2b0af5..3c73379 100755
--- a/plugins/FeedsProcessor.inc
+++ b/plugins/FeedsProcessor.inc
@@ -470,10 +470,10 @@ abstract class FeedsProcessor extends FeedsPlugin {
     // mapping on a prepopulated item such as an existing node.
     foreach ($this->config['mappings'] as $mapping) {
       if (isset($targets[$this->id][$mapping['target']]['real_target'])) {
-        unset($target_item->{$targets[$this->id][$mapping['target']]['real_target']});
+        $target_item->{$targets[$this->id][$mapping['target']]['real_target']} = NULL;
       }
-      elseif (isset($target_item->{$mapping['target']})) {
-        unset($target_item->{$mapping['target']});
+      else {
+        $target_item->{$mapping['target']} = NULL;
       }
     }