diff --git a/system/helpers/compatibility_helper.php b/system/helpers/compatibility_helper.php
deleted file mode 100644
index 6770d9a..0000000
--- a/system/helpers/compatibility_helper.php
+++ /dev/null
@@ -1,499 +0,0 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
-/**
- * CodeIgniter
- *
- * An open source application development framework for PHP 5.1.6 or newer
- *
- * @package		CodeIgniter
- * @author		ExpressionEngine Dev Team
- * @copyright	Copyright (c) 2008 - 2010, EllisLab, Inc.
- * @license		http://codeigniter.com/user_guide/license.html
- * @link		http://codeigniter.com
- * @since		Version 1.0
- * @filesource
- */
-
-// ------------------------------------------------------------------------
-
-/**
- * CodeIgniter Compatibility Helpers
- *
- * This helper contains some functions based on the PEAR PHP_Compat library
- * http://pear.php.net/package/PHP_Compat
- *
- * The PEAR compat library is a little bloated and the code doesn't harmonize
- * well with CodeIgniter, so those functions have been refactored.
- * We cheat a little and use CI's _exception_handler() to output our own PHP errors
- * so that the behavior fully mimicks the PHP 5 counterparts.  -- Derek Jones
- * @PHP4
- *
- * @package		CodeIgniter
- * @subpackage	Helpers
- * @category	Helpers
- * @author		ExpressionEngine Dev Team
- * @link		http://codeigniter.com/user_guide/helpers/compatibility_helper.html
- */
-
-// ------------------------------------------------------------------------
-
-if ( ! defined('PHP_EOL'))
-{
-	define('PHP_EOL', (DIRECTORY_SEPARATOR == '/') ? "\n" : "\r\n");
-}
-
-// ------------------------------------------------------------------------
-
-/**
- * file_put_contents()
- *
- * Writes a string to a file
- * http://us.php.net/manual/en/function.file_put_contents.php
- * argument 4, $context, not supported
- *
- * @access	public
- * @param	string		file name
- * @param	mixed		data to be written
- * @param	int			flags
- * @return	int			length of written string
- */
-if ( ! function_exists('file_put_contents'))
-{
-	function file_put_contents($filename, $data, $flags = NULL)
-	{
-		if (is_scalar($data))
-		{
-			settype($data, 'STRING');
-		}
-
-		if ( ! is_string($data) && ! is_array($data) && ! is_resource($data))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'file_put_contents(): the 2nd parameter should be either a string or an array', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		// read stream if given a stream resource
-		if (is_resource($data))
-		{
-			if (get_resource_type($data) !== 'stream')
-			{
-				$backtrace = debug_backtrace();
-				_exception_handler(E_USER_WARNING, 'file_put_contents(): supplied resource is not a valid stream resource', $backtrace[0]['file'], $backtrace[0]['line']);
-				return FALSE;
-			}
-
-			$text = '';
-
-			while ( ! feof($data))
-			{
-				$text .= fread($data, 4096);
-			}
-
-			$data = $text;
-			unset($text);
-		}
-
-		// strings only please!
-		if (is_array($data))
-		{
-			$data = implode('', $data);
-		}
-
-		// Set the appropriate mode
-		if (($flags & 8) > 0) // 8 = FILE_APPEND flag
-		{
-			$mode = FOPEN_WRITE_CREATE;
-		}
-		else
-		{
-			$mode = FOPEN_WRITE_CREATE_DESTRUCTIVE;
-		}
-
-		// Check if we're using the include path
-		if (($flags & 1) > 0) // 1 = FILE_USE_INCLUDE_PATH flag
-		{
-			$use_include_path = TRUE;
-		}
-		else
-		{
-			$use_include_path = FALSE;
-		}
-
-		$fp = @fopen($filename, $mode, $use_include_path);
-
-		if ($fp === FALSE)
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'file_put_contents('.htmlentities($filename).') failed to open stream', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		if (($flags & LOCK_EX) > 0)
-		{
-			if ( ! flock($fp, LOCK_EX))
-			{
-				$backtrace = debug_backtrace();
-				_exception_handler(E_USER_WARNING, 'file_put_contents('.htmlentities($filename).') unable to acquire an exclusive lock on file', $backtrace[0]['file'], $backtrace[0]['line']);
-				return FALSE;
-			}
-		}
-
-		// write it
-		if (($written = @fwrite($fp, $data)) === FALSE)
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'file_put_contents('.htmlentities($filename).') failed to write to '.htmlentities($filename), $backtrace[0]['file'], $backtrace[0]['line']);
-		}
-
-		// Close the handle
-		@fclose($fp);
-
-		// Return length
-		return $written;
-	}
-}
-
-// ------------------------------------------------------------------------
-
-/**
- * fputcsv()
- *
- * Format line as CSV and write to file pointer
- * http://us.php.net/manual/en/function.fputcsv.php
- *
- * @access	public
- * @param	resource	file pointer
- * @param	array		data to be written
- * @param	string		delimiter
- * @param	string		enclosure
- * @return	int			length of written string
- */
-if ( ! function_exists('fputcsv'))
-{
-	function fputcsv($handle, $fields, $delimiter = ',', $enclosure = '"')
-	{
-		// Checking for a handle resource
-		if ( ! is_resource($handle))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'fputcsv() expects parameter 1 to be stream resource, '.gettype($handle).' given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		// OK, it is a resource, but is it a stream?
-		if (get_resource_type($handle) !== 'stream')
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'fputcsv() expects parameter 1 to be stream resource, '.get_resource_type($handle).' given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		// Checking for an array of fields
-		if ( ! is_array($fields))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'fputcsv() expects parameter 2 to be array, '.gettype($fields).' given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		// validate delimiter
-		if (strlen($delimiter) > 1)
-		{
-			$delimiter = substr($delimiter, 0, 1);
-			$backtrace = debug_backtrace();
-			_exception_handler(E_NOTICE, 'fputcsv() delimiter must be one character long, "'.htmlentities($delimiter).'" used', $backtrace[0]['file'], $backtrace[0]['line']);
-		}
-
-		// validate enclosure
-		if (strlen($enclosure) > 1)
-		{
-			$enclosure = substr($enclosure, 0, 1);
-			$backtrace = debug_backtrace();
-			_exception_handler(E_NOTICE, 'fputcsv() enclosure must be one character long, "'.htmlentities($enclosure).'" used', $backtrace[0]['file'], $backtrace[0]['line']);
-
-		}
-
-		$out = '';
-
-		foreach ($fields as $cell)
-		{
-			$cell = str_replace($enclosure, $enclosure.$enclosure, $cell);
-
-			if (strpos($cell, $delimiter) !== FALSE OR strpos($cell, $enclosure) !== FALSE OR strpos($cell, "\n") !== FALSE)
-			{
-				$out .= $enclosure.$cell.$enclosure.$delimiter;
-			}
-			else
-			{
-				$out .= $cell.$delimiter;
-			}
-		}
-
-		$length = @fwrite($handle, substr($out, 0, -1)."\n");
-
-		return $length;
-	}
-}
-
-// ------------------------------------------------------------------------
-
-/**
- * stripos()
- *
- * Find position of first occurrence of a case-insensitive string
- * http://us.php.net/manual/en/function.stripos.php
- *
- * @access	public
- * @param	string		haystack
- * @param	string		needle
- * @param	int			offset
- * @return	int			numeric position of the first occurrence of needle in the haystack
- */
-if ( ! function_exists('stripos'))
-{
-	function stripos($haystack, $needle, $offset = NULL)
-	{
-		// Cast non string scalar values
-		if (is_scalar($haystack))
-		{
-			settype($haystack, 'STRING');
-		}
-
-		if ( ! is_string($haystack))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'stripos() expects parameter 1 to be string, '.gettype($haystack).' given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		if ( ! is_scalar($needle))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'stripos() needle is not a string or an integer in '.$backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		if (is_float($offset))
-		{
-			$offset = (int)$offset;
-		}
-
-		if ( ! is_int($offset) && ! is_bool($offset) && ! is_null($offset))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'stripos() expects parameter 3 to be long, '.gettype($offset).' given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return NULL;
-		}
-
-		return strpos(strtolower($haystack), strtolower($needle), $offset);
-	}
-}
-
-// ------------------------------------------------------------------------
-
-/**
- * str_ireplace()
- *
- * Find position of first occurrence of a case-insensitive string
- * http://us.php.net/manual/en/function.str-ireplace.php
- * (parameter 4, $count, is not supported as to do so in PHP 4 would make
- * it a required parameter)
- *
- * @access	public
- * @param	mixed		search
- * @param	mixed		replace
- * @param	mixed		subject
- * @return	int			numeric position of the first occurrence of needle in the haystack
- */
-if ( ! function_exists('str_ireplace'))
-{
-	function str_ireplace($search, $replace, $subject)
-	{
-		// Nothing to do here
-		if ($search === NULL OR $subject === NULL)
-		{
-			return $subject;
-		}
-
-		// Crazy arguments
-		if (is_scalar($search) && is_array($replace))
-		{
-			$backtrace = debug_backtrace();
-
-			if (is_object($replace))
-			{
-				show_error('Object of class '.get_class($replace).' could not be converted to string in '.$backtrace[0]['file'].' on line '.$backtrace[0]['line']);
-			}
-			else
-			{
-				_exception_handler(E_USER_NOTICE, 'Array to string conversion in '.$backtrace[0]['file'], $backtrace[0]['line']);
-			}
-		}
-
-		// Searching for an array
-		if (is_array($search))
-		{
-			// Replacing with an array
-			if (is_array($replace))
-			{
-				$search = array_values($search);
-				$replace = array_values($replace);
-
-				if (count($search) >= count($replace))
-				{
-					$replace = array_pad($replace, count($search), '');
-				}
-				else
-				{
-					$replace = array_slice($replace, 0, count($search));
-				}
-			}
-			else
-			{
-				// Replacing with a string all positions
-				$replace = array_fill(0, count($search), $replace);
-			}
-		}
-		else
-		{
-			//Searching for a string and replacing with a string.
-			$search  = array((string)$search);
-			$replace = array((string)$replace);
-		}
-
-		// Prepare the search array
-		foreach ($search as $search_key => $search_value)
-		{
-			$search[$search_key] = '/'.preg_quote($search_value, '/').'/i';
-		}
-
-		// Prepare the replace array (escape backreferences)
-		foreach ($replace as $k => $v)
-		{
-			$replace[$k] = str_replace(array(chr(92), '$'), array(chr(92).chr(92), '\$'), $v);
-		}
-
-		// do the replacement
-		$result = preg_replace($search, $replace, (array)$subject);
-
-		// Check if subject was initially a string and return it as a string
-		if ( ! is_array($subject))
-		{
-			return current($result);
-		}
-
-		// Otherwise, just return the array
-		return $result;
-	}
-}
-
-// ------------------------------------------------------------------------
-
-/**
- * http_build_query()
- *
- * Generate URL-encoded query string
- * http://us.php.net/manual/en/function.http-build-query.php
- *
- * @access	public
- * @param	array		form data
- * @param	string		numeric prefix
- * @param	string		argument separator
- * @return	string		URL-encoded string
- */
-if ( ! function_exists('http_build_query'))
-{
-	function http_build_query($formdata, $numeric_prefix = NULL, $separator = NULL)
-	{
-		// Check the data
-		if ( ! is_array($formdata) && ! is_object($formdata))
-		{
-			$backtrace = debug_backtrace();
-			_exception_handler(E_USER_WARNING, 'http_build_query() Parameter 1 expected to be Array or Object. Incorrect value given', $backtrace[0]['file'], $backtrace[0]['line']);
-			return FALSE;
-		}
-
-		// Cast it as array
-		if (is_object($formdata))
-		{
-			$formdata = get_object_vars($formdata);
-		}
-
-		// If the array is empty, return NULL
-		if (empty($formdata))
-		{
-			return NULL;
-		}
-
-		// Argument separator
-		if ($separator === NULL)
-		{
-			$separator = ini_get('arg_separator.output');
-
-			if (strlen($separator) == 0)
-			{
-				$separator = '&';
-			}
-		}
-
-		// Start building the query
-		$tmp = array();
-
-		foreach ($formdata as $key => $val)
-		{
-			if ($val === NULL)
-			{
-				continue;
-			}
-
-			if (is_integer($key) && $numeric_prefix != NULL)
-			{
-				$key = $numeric_prefix.$key;
-			}
-
-			if (is_resource($val))
-			{
-				return NULL;
-			}
-
-			// hand it off to a recursive parser
-			$tmp[] = _http_build_query_helper($key, $val, $separator);
-		}
-
-		return implode($separator, $tmp);
-	}
-
-
-	// Helper helper.  Remind anyone of college?
-	// Required to handle recursion in nested arrays.
-	//
-	// You could shave fractions of fractions of a second by moving where
-	// the urlencoding takes place, but it's much less intuitive, and if
-	// your application has 10,000 form fields, well, you have other problems ;)
-	function _http_build_query_helper($key, $val, $separator = '&')
-	{
-		if (is_scalar($val))
-		{
-			return urlencode($key).'='.urlencode($val);
-		}
-		else
-		{
-			// arrays please
-			if (is_object($val))
-			{
-				$val = get_object_vars($val);
-			}
-
-			foreach ($val as $k => $v)
-			{
-				$tmp[] = _http_build_query_helper($key.'['.$k.']', $v, $separator);
-			}
-		}
-
-		return implode($separator, $tmp);
-	}
-}
-
-
-/* End of file compatibility_helper.php */
-/* Location: ./system/helpers/compatibility_helper.php */
\ No newline at end of file
diff --git a/user_guide/general/reserved_names.html b/user_guide/general/reserved_names.html
index 7ab518d..3115d6a 100644
--- a/user_guide/general/reserved_names.html
+++ b/user_guide/general/reserved_names.html
@@ -67,34 +67,9 @@
 	<li>Controller</li>
 	<li>CI_Base</li>
 	<li>_ci_initialize</li>
-	<li>Default (PHP 5)</li>
+	<li>Default</li>
 	<li>index</li>
 </ul>
-<p><br /><!-- @PHP4 -->
-	If you are running PHP 4 there are some additional reserved names. These ONLY apply if you are running PHP 4.</p>
-<ul>
-	<li>CI_Loader</li>
-	<li>config</li>
-	<li>database</li>
-	<li>dbutil</li>
-	<li>dbforge</li>
-	<li>file</li>
-	<li>helper</li>
-	<li>helpers</li>
-	<li>language</li>
-	<li>library</li>
-	<li>model</li>
-	<li>script</li>
-	<li>view</li>
-	<li>vars</li>
-	<li>_ci_assign_to_models</li>
-	<li>_ci_autoloader</li>
-	<li>_ci_init_class</li>
-	<li>_ci_is_instance</li>
-	<li>_ci_load</li>
-	<li>_ci_load_class</li>
-	<li>_ci_object_to_array</li>
-</ul>
 <h3>Functions</h3>
 <ul>
 	<li>is_really_writable()</li>
diff --git a/user_guide/helpers/compatibility_helper.html b/user_guide/helpers/compatibility_helper.html
deleted file mode 100644
index 9afec65..0000000
--- a/user_guide/helpers/compatibility_helper.html
+++ /dev/null
@@ -1,118 +0,0 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
-<head>
-
-<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-<title>Compatibility Helper : CodeIgniter User Guide</title>
-
-<style type='text/css' media='all'>@import url('../userguide.css');</style>
-<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' />
-
-<script type="text/javascript" src="../nav/nav.js"></script>
-<script type="text/javascript" src="../nav/prototype.lite.js"></script>
-<script type="text/javascript" src="../nav/moo.fx.js"></script>
-<script type="text/javascript" src="../nav/user_guide_menu.js"></script>
-
-<meta http-equiv='expires' content='-1' />
-<meta http-equiv= 'pragma' content='no-cache' />
-<meta name='robots' content='all' />
-<meta name='author' content='ExpressionEngine Dev Team' />
-<meta name='description' content='CodeIgniter User Guide' />
-
-</head>
-<body>
-
-<!-- START NAVIGATION -->
-<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div>
-<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div>
-<div id="masthead">
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td><h1>CodeIgniter User Guide Version 2.0.0</h1></td>
-<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td>
-</tr>
-</table>
-</div>
-<!-- END NAVIGATION -->
-
-
-<!-- START BREADCRUMB -->
-
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td id="breadcrumb">
-<a href="http://codeigniter.com/">CodeIgniter Home</a> &nbsp;&#8250;&nbsp;
-<a href="../index.html">User Guide Home</a> &nbsp;&#8250;&nbsp;
-Compatibility Helper
-</td>
-<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide&nbsp; <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" />&nbsp;<input type="submit" class="submit" name="sa" value="Go" /></form></td>
-</tr>
-</table>
-<!-- END BREADCRUMB -->
-
-<br clear="all" />
-
-
-<!-- START CONTENT -->
-<div id="content">
-
-
-<h1>Compatibility Helper</h1>
-
-<p>The Compatibility Helper file contains PHP 4 implementations of some PHP 5 only native PHP functions and constants.  This can be useful
-	if you'd like to take advantage of some of these native function but your application may end up running on a PHP 4 server.
-	In these cases, it may be advantageous to <a href="../general/autoloader.html">Auto-load</a> the Compatibility Helper so you
-	do not have to load it in each controller.</p>
-
-<p class="important"><strong>Note:</strong> There are a few compatibility functions that are in CodeIgniter's native Compat.php file.
-	You may use those functions without loading this helper.  The functions are split between that file and this Helper so that only
-	functions required by the framework are included by default.  This way, whether or not you load the additional functions in this Helper
-	remains your choice.</p>
-
-<h2>Loading this Helper</h2>
-
-<p>This helper is loaded using the following code:</p>
-<code>$this->load->helper('compatibility');</code>
-
-<h2>Available Constants</h2>
-<p>The following constants are available:</p>
-
-<h3>PHP_EOL</h3>
-<p>The newline character for the server's current OS, e.g. on Windows systems "\r\n", on *nix "\n".
-
-<h2>Available Functions</h2>
-<p>The following functions are available (see linked PHP documentation for documentation):</p>
-
-<h3><a href="http://us.php.net/manual/en/function.file-put-contents.php">file_put_contents()</a> - The fourth parameter, <var>$context</var>, is not supported.</h3>
-
-<h3><a href="http://us.php.net/manual/en/function.fputcsv.php">fputcsv()</a></h3>
-
-<h3><a href="http://us.php.net/manual/en/function.http-build-query.php">http_build_query()</a></h3>
-
-<h3><a href="http://us.php.net/manual/en/function.str-ireplace.php">str_ireplace()</a> - The fourth parameter, <var>$count</var>, is not supported, as PHP 4 would make it become required.</h3>
-
-<h3><a href="http://us.php.net/manual/en/function.stripos.php">stripos()</a></h3>
-
-
-
-
-
-
-
-</div>
-<!-- END CONTENT -->
-
-
-<div id="footer">
-<p>
-Previous Topic:&nbsp;&nbsp;<a href="array_helper.html">Array Helper</a>
-&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-<a href="#top">Top of Page</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-<a href="../index.html">User Guide Home</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-Next Topic:&nbsp;&nbsp;<a href="cookie_helper.html">Cookie Helper</a>
-</p>
-<p><a href="http://codeigniter.com">CodeIgniter</a> &nbsp;&middot;&nbsp; Copyright &#169; 2006-2010 &nbsp;&middot;&nbsp; <a href="http://ellislab.com/">EllisLab, Inc.</a></p>
-</div>
-
-</body>
-</html>
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