diff --git a/modules/casserver/www/serviceValidate.php b/modules/casserver/www/serviceValidate.php
index e893a815a246bb31a2ee93f7bd7f4eb0da94b44f..86ca87f2b74a10f4f3943e61329f9cc876ec4f6f 100644
--- a/modules/casserver/www/serviceValidate.php
+++ b/modules/casserver/www/serviceValidate.php
@@ -83,7 +83,7 @@ function returnResponse($value, $function, $usrname = '', $attributes = array(),
 		'</cas:authenticationSuccess>
 </cas:serviceResponse>';
 		} else {
-			echo 'YES' . "\n" . $usrname;
+			echo 'yes' . "\n" . $usrname;
 		}
 	} else {
 		if ($function == 'serviceValidate') {
@@ -92,7 +92,7 @@ function returnResponse($value, $function, $usrname = '', $attributes = array(),
 </cas:authenticationFailure>
 </cas:serviceResponse>';
 		} else {
-			echo 'NO';
+			echo 'no';
 
 		}
 	}