Update: modified return bool value on comment
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index a34809e..c78583f 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -1079,7 +1079,7 @@
 	 *
 	 * @access	public
 	 * @param	string
-	 * @return	string
+	 * @return	bool
 	 */
 	public function valid_ip($ip)
 	{