diff --git a/potx.inc b/potx.inc
index 83de34b..ba6f75f 100644
--- a/potx.inc
+++ b/potx.inc
@@ -2791,10 +2791,10 @@ function _potx_parse_shipped_configuration($save_callback = '_potx_save_string',
  *   The list of fully qualified module names.
  */
 function _potx_load_matching_qualified_modules($module_names) {
-  global $potx_callbacks;
+  global $_potx_callbacks;
   $qualified_modules = array();
   foreach ($module_names as $module_name) {
-    $qualified_name = $potx_callbacks['find_matching_qualified_module']($module_name);
+    $qualified_name = $_potx_callbacks['find_matching_qualified_module']($module_name);
     if ($qualified_name !== FALSE) {
       $qualified_modules[] = $qualified_name;
     }