diff -urw dam.orig/lib/class.tx_dam_querygen.php dam/lib/class.tx_dam_querygen.php
--- dam.orig/lib/class.tx_dam_querygen.php	2006-05-15 21:42:08.000000000 +0200
+++ dam/lib/class.tx_dam_querygen.php	2006-05-15 22:49:31.000000000 +0200
@@ -423,7 +423,7 @@
 
 			$query = array();
 			foreach($select['LEFT_JOIN'] as $table => $on) {
-				$query[] = 'LEFT JOIN '.$table.' ON ('.$on.')';
+				$query[] = 'LEFT JOIN '.$table.' ON '.$on;
 			}
 			$queryParts['FROM'].= "\n".implode ("\n",$query);