diff --git a/includes/install.inc b/includes/install.inc
index 472cc94077f882406f19f16b1e9951123219d634..c62039091e3fd4a7c9d87a0ae81187d12c39d180 100644
--- a/includes/install.inc
+++ b/includes/install.inc
@@ -29,8 +29,11 @@
 function drupal_get_schema_versions($module) {
   $functions = get_defined_functions();
   foreach ($functions['user'] as $function) {
-    if (strpos($function, $module .'_update') === 0) {
-      $updates[] = (int) substr($function, strlen($module .'_update_'));
+    if (strpos($function, $module .'_update_') === 0) {
+      $version = substr($function, strlen($module .'_update_'));
+      if (is_numeric($version)) {
+        $updates[] = $version;
+      }
     }
   }
   if (count($updates) == 0) {
diff --git a/update.php b/update.php
index 9b16492baf2e99aeb03efd7d13d22c50cffe0ddf..14c19e4d0681f5e741aa91d476d9d1fb91ae02e6 100644
--- a/update.php
+++ b/update.php
@@ -292,8 +292,9 @@ function update_selection_page() {
     '#collapsed' => TRUE,
   );
   foreach (module_list() as $module) {
-    if (module_hook($module, 'version')) {
-      $updates = drupal_map_assoc(drupal_get_schema_versions($module));
+    $updates = drupal_get_schema_versions($module);
+    if ($updates !== FALSE) {
+      $updates = drupal_map_assoc($updates);
       $updates[] = 'No updates available';
 
       $form['start'][$module] = array(