diff --git a/lib/cas/client.php b/lib/cas/client.php
index a4fbfd95914..7b878642418 100644
--- a/lib/cas/client.php
+++ b/lib/cas/client.php
@@ -1747,7 +1747,7 @@ class CASClient
       if ( !($dom = domxml_open_mem($text_response))) {
     // read failed
     $this->authError('PT not validated',
-             $alidate_url,
+             $validate_url,
              FALSE/*$no_response*/,
              TRUE/*$bad_response*/,
              $text_response);
@@ -1947,4 +1947,4 @@ class CASClient
   /** @} */
 }
 
-?>
\ No newline at end of file
+?>