diff --git a/user_guide_src/source/general/compatibility_functions.rst b/user_guide_src/source/general/compatibility_functions.rst
index 434b098..936f2a2 100644
--- a/user_guide_src/source/general/compatibility_functions.rst
+++ b/user_guide_src/source/general/compatibility_functions.rst
@@ -222,29 +222,6 @@
 	For more information, please refer to the `PHP manual for
 	array_column() <http://php.net/array_column>`_.
 
-.. php:function:: array_replace(array $array1[, ...])
-
-	:param	array	$array1: Array in which to replace elements
-	:param	array	...: Array (or multiple ones) from which to extract elements
-	:returns:	Modified array
-	:rtype:	array
-
-	For more information, please refer to the `PHP manual for
-	array_replace() <http://php.net/array_replace>`_.
-
-.. php:function:: array_replace_recursive(array $array1[, ...])
-
-	:param	array	$array1: Array in which to replace elements
-	:param	array	...: Array (or multiple ones) from which to extract elements
-	:returns:	Modified array
-	:rtype:	array
-
-	For more information, please refer to the `PHP manual for
-	array_replace_recursive() <http://php.net/array_replace_recursive>`_.
-
-	.. important:: Only PHP's native function can detect endless recursion.
-		Unless you are running PHP 5.3+, be careful with references!
-
 .. php:function:: hex2bin($data)
 
 	:param	array	$data: Hexadecimal representation of data
@@ -253,12 +230,3 @@
 
 	For more information, please refer to the `PHP manual for hex2bin()
 	<http://php.net/hex2bin>`_.
-
-.. php:function:: quoted_printable_encode($str)
-
-	:param	string	$str: Input string
-	:returns:	8bit-encoded string
-	:rtype:	string
-
-	For more information, please refer to the `PHP manual for
-	quoted_printable_encode() <http://php.net/quoted_printable_encode>`_.
\ No newline at end of file
diff --git a/user_guide_src/source/general/hooks.rst b/user_guide_src/source/general/hooks.rst
index ffe3fef..6cc3407 100644
--- a/user_guide_src/source/general/hooks.rst
+++ b/user_guide_src/source/general/hooks.rst
@@ -56,8 +56,8 @@
 -  **params** Any parameters you wish to pass to your script. This item
    is optional.
 
-If you're running PHP 5.3+, you can also use lambda/anoymous functions
-(or closures) as hooks, with a simpler syntax::
+You can also use lambda/anoymous functions (or closures) as hooks, with
+a simpler syntax::
 
 	$hook['post_controller'] = function()
 	{
diff --git a/user_guide_src/source/general/routing.rst b/user_guide_src/source/general/routing.rst
index 5153680..b53a85d 100644
--- a/user_guide_src/source/general/routing.rst
+++ b/user_guide_src/source/general/routing.rst
@@ -133,8 +133,8 @@
 Callbacks
 =========
 
-If you are using PHP >= 5.3 you can use callbacks in place of the normal
-routing rules to process the back-references. Example::
+You can also use callbacks in place of the normal routing rules to process
+the back-references. Example::
 
 	$route['products/([a-zA-Z]+)/edit/(\d+)'] = function ($product_type, $id)
 	{
diff --git a/user_guide_src/source/general/security.rst b/user_guide_src/source/general/security.rst
index 8afdaca..744a2c9 100644
--- a/user_guide_src/source/general/security.rst
+++ b/user_guide_src/source/general/security.rst
@@ -133,12 +133,7 @@
    in PHP's own `Password Hashing <http://php.net/password>`_ functions.
 
    Please use them, even if you're not running PHP 5.5+, CodeIgniter
-   provides them for you as long as you're running at least PHP version
-   5.3.7 (and if you don't meet that requirement - please, upgrade).
-
-   If you're one of the really unlucky people who can't even upgrade to a
-   more recent PHP version, use `hash_pbkdf() <http://php.net/hash_pbkdf2>`,
-   which we also provide in our compatibility layer.
+   provides them for you.
 
 -  DO NOT ever display or send a password in plain-text format!