diff --git a/src/applications/typeahead/datasource/PhabricatorTypeaheadDatasource.php b/src/applications/typeahead/datasource/PhabricatorTypeaheadDatasource.php
--- a/src/applications/typeahead/datasource/PhabricatorTypeaheadDatasource.php
+++ b/src/applications/typeahead/datasource/PhabricatorTypeaheadDatasource.php
@@ -107,7 +107,7 @@
       return array();
     }
 
-    $tokens = preg_split('/\s+|[-\[\]]/', $string);
+    $tokens = preg_split('/\s+|[-\[\]]/u', $string);
     return array_unique($tokens);
   }