diff --git a/node_convert.install b/node_convert.install
index d5884f8..0789ffe 100644
--- a/node_convert.install
+++ b/node_convert.install
@@ -10,6 +10,9 @@
  * @see http://drupal.org/node/1354
  */
 function node_convert_schema() {
+  // Load our module file so the PHP constants are defined.
+  module_load_include('module', 'node_convert');
+
   $schema[NODE_CONVERT_TEMPLATE_TABLE] = array(
     // CTools export definitions.
     'export' => array(
@@ -104,4 +107,4 @@ function node_convert_update_7001(&$sandbox) {
     module_load_include('module', 'node_convert');
     _node_convert_recreate_identifiers();
   }
-}
\ No newline at end of file
+}