diff --git modules/update/tests/update_test.module modules/update/tests/update_test.module
index 1ab30b0..abf11e8 100644
--- modules/update/tests/update_test.module
+++ modules/update/tests/update_test.module
@@ -112,3 +112,23 @@ function update_test_archiver_info() {
     ),
   );
 }
+
+/**
+ * Implements hook_updater_info().
+ */
+function update_test_updater_info() {
+  // This fake updater class should, because it's a very
+  // low weight, be selected for all module update
+ // attempts.
+  return array(
+    'module_test' => array(
+      'class' => 'UpdateTestModuleUpdater',
+      'name' => t('Update modules, test version'),
+      'weight' => -100,
+    ),
+  );
+}
+
+class UpdateTestModuleUpdater extends ModuleUpdater {
+
+}
\ No newline at end of file
diff --git modules/update/update.test modules/update/update.test
index 0db9158..d3170e7 100644
--- modules/update/update.test
+++ modules/update/update.test
@@ -664,3 +664,32 @@ class UpdateTestUploadCase extends UpdateTestHelper {
   }
 
 }
+
+class UpdateExtensibilityTestCase extends UpdateTestHelper {
+
+  public static function getInfo() {
+    return array(
+      'name' => 'Update extensibility functionality',
+      'description' => 'Tests the update module to ensure it can be properly extended from contrib..',
+      'group' => 'Update',
+    );
+  }
+
+  function setUp() {
+    parent::setUp('update_test', 'update');
+  }
+
+  /**
+   * Tests the update module when no updates are available.
+   */
+  function testAddNewModuleUpdater() {
+
+      // Make sure the Updater registry is loaded.
+      drupal_get_updaters();
+
+      $updater = Updater::factory('modules/system');
+
+      $this->assertTrue($updater instanceof UpdateTestModuleUpdater, t('Correct Updater class returned.'));
+   }
+
+}
\ No newline at end of file