diff --git a/system/libraries/Migration.php b/system/libraries/Migration.php
index fd915c3..b673e9c 100644
--- a/system/libraries/Migration.php
+++ b/system/libraries/Migration.php
@@ -104,8 +104,8 @@
 	 */
 	public function __construct($config = array())
 	{
-		# Only run this constructor on main library load
-		if (get_parent_class($this) !== FALSE)
+		// Only run this constructor on main library load
+		if ( ! in_array(get_class($this), array('CI_Migration', config_item('subclass_prefix').'Migration'), TRUE))
 		{
 			return;
 		}
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index daa1cfc..de88dcf 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -480,6 +480,7 @@
 -  Fixed a bug - SQLSRV didn't support ``escape_like_str()`` or escaping an array of values.
 -  Fixed a bug - :doc:`DB result <database/results>` method ``list_fields()`` didn't reset its field pointer for the *mysql*, *mysqli* and *mssql* drivers.
 -  Fixed a bug (#73) - :doc:`Security Library <libraries/security>` method ``sanitize_filename()`` could be tricked by an XSS attack.
+-  Fixed a bug (#2211) - :doc:`Migration Library <libraries/migration>` extensions couldn't execute ``CI_Migration::__construct()``.
 
 Version 2.1.3
 =============