diff --git a/auth/cas/config.html b/auth/cas/config.html
index ea603acc046..d6e1f91009d 100644
--- a/auth/cas/config.html
+++ b/auth/cas/config.html
@@ -1,13 +1,27 @@
 <?php
     require_once('languages.php');
     // Initialize vars
-    optional_variable($config->cas_hostname,"");
-    optional_variable($config->cas_port,"");
-    optional_variable($config->cas_version,"");
-    optional_variable($config->cas_baseuri,"");
-    optional_variable($config->cas_language,"");
-    optional_variable($config->cas_use_cas,"");
-    optional_variable($config->cas_create_user,"0");
+    if (!isset ($config->cas_hostname)) {
+        $config->cas_hostname = "";
+    }
+    if (!isset ($config->cas_port)) {
+        $config->cas_port = "";
+    }
+    if (!isset ($config->cas_version)) {
+        $config->cas_version = "";
+    }
+    if (!isset ($config->cas_baseuri)) {
+        $config->cas_baseuri = "";
+    }
+    if (!isset ($config->cas_language)) {
+        $config->cas_language = "";
+    }
+    if (!isset ($config->cas_use_cas)) {
+        $config->cas_use_cas = "";
+    }
+    if (!isset ($config->cas_create_user)) {
+        $config->cas_create_user = "0";
+    }
 ?>