diff --git a/Smarty/Smarty.class.php b/Smarty/Smarty.class.php
index b298c3276..aa2c3fe59 100644
--- a/Smarty/Smarty.class.php
+++ b/Smarty/Smarty.class.php
@@ -1107,8 +1107,8 @@ public function templateExists($resource_name) {
    *
    * @return \Smarty current Smarty instance for chaining
    */
-  public function setTemplateDir($template_dir, $isConfig = false) {
-    $this->addTemplateDir($template_dir, null, $isConfig);
+  public function setTemplateDir($template_dir) {
+    $this->template_dir = (array) $template_dir;
     return $this;
   }