diff --git a/code/TrackBackURL.php b/code/TrackBackURL.php
index 0959903..7cf0903 100644
--- a/code/TrackBackURL.php
+++ b/code/TrackBackURL.php
@@ -42,7 +42,7 @@ class TrackBackURL extends DataObject {
 	 * @return boolean
 	 */ 
 	function isDuplicate($onPung = false) {
-		$where = "\"BlogEntryID\" = {$this->BlogEntryID} AND \"URL\" = '{$this->URL}' AND TrackBackURL.ID <> {$this->ID}"; 
+		$where = "\"BlogEntryID\" = {$this->BlogEntryID} AND \"URL\" = '{$this->URL}' AND \"TrackBackURL\".\"ID\" <> {$this->ID}"; 
 		if($onPung) $where .= " AND \"Pung\" = 1"; 
 
 		if(DataObject::get_one($this->ClassName, $where)) {