diff --git a/lib/managedaction.php b/lib/managedaction.php
index 4caf977210..808c4af7cc 100644
--- a/lib/managedaction.php
+++ b/lib/managedaction.php
@@ -80,8 +80,7 @@ class ManagedAction extends Action
         if (empty($_POST) && $_SERVER['CONTENT_LENGTH']>0) {
             // TRANS: Client error displayed when the number of bytes in a POST request exceeds a limit.
             // TRANS: %s is the number of bytes of the CONTENT_LENGTH.
-            $msg = _m('The server was unable to handle that much POST data (%s MiB) due to its current configuration.',
-                      'The server was unable to handle that much POST data (%s MiB) due to its current configuration.',
+            $msg = sprintf(_m('The server was unable to handle that much POST data (%s MiB) due to its current configuration.'),
                       round($_SERVER['CONTENT_LENGTH']/1024/1024,2));
             throw new ClientException($msg);
         }