better check for empty links

diff --git a/DataObjects/Mtrack_change.php b/DataObjects/Mtrack_change.php
index b4e6f63..259fc50 100644 (file)
--- a/DataObjects/Mtrack_change.php
+++ b/DataObjects/Mtrack_change.php
@@ -501,8 +501,8 @@ class Pman_MTrack_DataObjects_Mtrack_change extends DB_DataObject
                 if (in_array($k, $keys)) {
                     continue;
                 } 
-                $alinks = explode(':', $links[$k]);
-                if (isset($links[$k]) && $this->tablename() == array_shift($alinks)) {
+                $alinks = isset($links[$k])  ? explode(':', $links[$k]) : false;
+                if ($alinks && $this->tablename() == array_shift($alinks)) {
                     continue;
                 }
                 $ret += $this->add($fieldname .':'. $k, $new->{$k}, !$old ? '' :  $old->{$k});