--- system.js	2009-01-12 14:27:56.000000000 -0600
+++ system.js 	2009-01-12 14:27:08.000000000 -0600
@@ -72,11 +72,11 @@
 Drupal.behaviors.copyFieldValue = function (context) {
   for (var sourceId in Drupal.settings.copyFieldValue) {
     // Get the list of target fields.
-    targetIds = Drupal.settings.copyFieldValue[sourceId];
     if (!$('#'+ sourceId + '.copy-field-values-processed').size(), context) {
       // Add the behavior to update target fields on blur of the primary field.
       sourceField = $('#' + sourceId);
       sourceField.bind('blur', function(e) {
+        targetIds = Drupal.settings.copyFieldValue[this.id];
         for (var delta in targetIds) {
           var targetField = $('#'+ targetIds[delta]);
           if (targetField.val() == '') {