Index: content.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/cck/content.module,v
retrieving revision 1.90.2.45
diff -u -r1.90.2.45 content.module
--- content.module	14 Nov 2007 00:02:53 -0000	1.90.2.45
+++ content.module	20 Nov 2007 07:20:47 -0000
@@ -621,7 +621,7 @@
       if (function_exists($function)) {
         // If we're building a node creation form, pre-fill with default values
         if ($op == 'prepare form values' && empty($node->nid)) {
-          $node_field = array_merge($node_field, content_default_value($node, $field, $node_field));
+          $node_field += content_default_value($node, $field, $node_field);
         }
 
         $result = $function($op, $node, $field, $node_field);