diff --git a/system/database/drivers/interbase/interbase_utility.php b/system/database/drivers/interbase/interbase_utility.php
index 1b92af9..1642118 100644
--- a/system/database/drivers/interbase/interbase_utility.php
+++ b/system/database/drivers/interbase/interbase_utility.php
@@ -42,7 +42,7 @@
 	 * @param	string	$filename
 	 * @return	mixed
 	 */
-	protected function backup($filename)
+	protected function _backup($filename)
 	{
 		if ($service = ibase_service_attach($this->db->hostname, $this->db->username, $this->db->password))
 		{