Index: term_reference_tree.module
===================================================================
--- term_reference_tree.module	(revision 606)
+++ term_reference_tree.module	(working copy)
@@ -131,6 +131,8 @@
  *   An array of taxonomy terms, each in the form array('tid' => $tid, 'name' => $name)
  */
 function _term_reference_tree_get_children($tid, $vid) {
+  global $language;
+  
   // DO NOT LOAD TAXONOMY TERMS HERE
   // Taxonomy terms take a lot of time and memory to load, and this can be
   // very bad on large vocabularies.  Instead, we load the term as necessary
@@ -140,6 +142,7 @@
   $select->join('taxonomy_term_hierarchy', 'h', 'd.tid = h.tid');
   $result = $select->fields('d', array('tid', 'vid', 'name'))
     ->condition('d.vid', $vid, '=')
+    ->condition('d.language', $language->language, '=')
     ->condition('h.parent', $tid, '=')
     ->orderBy('weight')
     ->orderBy('name')