diff --git a/libs/plugins/modifier.string_format.php b/libs/plugins/modifier.string_format.php
index 59b75edb..3cb55da7 100644
--- a/libs/plugins/modifier.string_format.php
+++ b/libs/plugins/modifier.string_format.php
@@ -10,7 +10,7 @@
  */
 function smarty_modifier_string_format($string, $format)
 {
-    return sprintf($string, $format);
+    return sprintf($format, $string);
 }
 
 /* vim: set expandtab: */