diff --git cas.module cas.module
index 0720031..ee8c6ff 100644
--- cas.module
+++ cas.module
@@ -34,10 +34,10 @@ define('CAS_AUTHMAP_INTERNAL', 1);  // Use drupal as the internal user.
  *   The cas reply string to transform into a drupal username
  */
 function cas_invoke_auth_transform(&$cas_name) {
-  foreach (module_implements('auth_transform') as $module) {
-    $function = $module . '_auth_transform';
+  foreach (module_implements('cas_auth_transform') as $module) {
+    $function = $module . '_cas_auth_transform';
     if (function_exists($function)) {
-      $function('cas', $cas_name);
+      $function($cas_name);
     }
   }
 }
@@ -56,11 +56,10 @@ function cas_invoke_auth_transform(&$cas_name) {
  *   FALSE if any module returned FALSE
  */
 function cas_invoke_auth_filter($cas_name) {
-  foreach (module_implements('auth_filter') as $module) {
-    $function = $module . '_auth_filter';
+  foreach (module_implements('cas_auth_filter') as $module) {
+    $function = $module . '_cas_auth_filter';
     if (function_exists($function)) {
- 
-      if (($return = $function('cas', $cas_name)) === FALSE) {
+      if ($function($cas_name) === FALSE) {
         return FALSE;
       }
     }