Fix #62 Adding CI_ prefix to Controller.
diff --git a/application/controllers/welcome.php b/application/controllers/welcome.php
index 2e4cff8..3c2f7e1 100644
--- a/application/controllers/welcome.php
+++ b/application/controllers/welcome.php
@@ -1,10 +1,10 @@
 <?php
 
-class Welcome extends Controller {
+class Welcome extends CI_Controller {
 
 	function Welcome()
 	{
-		parent::Controller();
+		parent::CI_Controller();
 	}
 
 	function index()
diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index e701cc3..3dfefc2 100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -261,7 +261,7 @@
 	if ( ! class_exists($class)
 		OR $method == 'controller'
 		OR strncmp($method, '_', 1) == 0
-		OR in_array(strtolower($method), array_map('strtolower', get_class_methods('Controller')))
+		OR in_array(strtolower($method), array_map('strtolower', get_class_methods('CI_Controller')))
 		)
 	{
 		show_404("{$class}/{$method}");
diff --git a/system/core/Controller.php b/system/core/Controller.php
index 9bd9912..e250caf 100644
--- a/system/core/Controller.php
+++ b/system/core/Controller.php
@@ -27,17 +27,17 @@
  * @author		ExpressionEngine Dev Team
  * @link		http://codeigniter.com/user_guide/general/controllers.html
  */
-class Controller extends CI_Base {
+class CI_Controller extends CI_Base {
 
 	/**
 	 * Constructor
 	 *
 	 * Calls the initialize() function
 	 */
-	function Controller()
+	function CI_Controller()
 	{
 		parent::CI_Base();
-
+		
 		// Assign all the class objects that were instantiated by the
 		// bootstrap file (CodeIgniter.php) to local class variables
 		// so that CI can run as one big super object.
diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index 5bfbee7..67fcb7e 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -75,6 +75,7 @@
 			<li>Added ability to set "Package" paths - specific paths where the Loader and Config classes should try to look first for a requested file.  This allows distribution of sub-applications with their own libraries, models, config files, etc. in a single "package" directory.  See the <a href="libraries/loader.html">Loader class</a> documentation for more details.</li>
 			<li>In-development code is now hosted at <a href="http://bitbucket.org/ellislab/codeigniter/">BitBucket</a>.</li>
 			<li>Removed the deprecated Validation Class.</li>
+			<li>Added CI_ Prefix to all core classes.</li>
 		</ul>
 	<li>Libraries
 		<ul>
diff --git a/user_guide/general/controllers.html b/user_guide/general/controllers.html
index 782fbfa..9da1da2 100644
--- a/user_guide/general/controllers.html
+++ b/user_guide/general/controllers.html
@@ -96,7 +96,7 @@
 
 <textarea class="textarea" style="width:100%" cols="50" rows="10">
 &lt;?php
-class Blog extends Controller {
+class Blog extends CI_Controller {
 
 	function index()
 	{
@@ -119,7 +119,7 @@
 <p>Note: Class names must start with an uppercase letter.  In other words, this is valid:</p>
 
 <code>&lt;?php<br />
-class <var>Blog</var> extends Controller {<br />
+class <var>Blog</var> extends CI_Controller {<br />
 <br />
 }<br />
 ?&gt;</code>
@@ -127,7 +127,7 @@
 <p>This is <strong>not</strong> valid:</p>
 
 <code>&lt;?php<br />
-class <var>blog</var> extends Controller {<br />
+class <var>blog</var> extends CI_Controller {<br />
 <br />
 }<br />
 ?&gt;</code>
@@ -151,7 +151,7 @@
 
 <textarea class="textarea" style="width:100%" cols="50" rows="15">
 &lt;?php
-class Blog extends Controller {
+class Blog extends CI_Controller {
 
 	function index()
 	{
@@ -185,7 +185,7 @@
 
 <code>
 &lt;?php<br />
-class Products extends Controller {<br />
+class Products extends CI_Controller {<br />
 <br />
 &nbsp;&nbsp;&nbsp;&nbsp;function shoes($sandals, $id)<br />
 &nbsp;&nbsp;&nbsp;&nbsp;{<br />
@@ -329,7 +329,7 @@
 
 <p>If you intend to use a constructor in any of your Controllers, you <strong>MUST</strong> place the following line of code in it:</p>
 
-<code>parent::Controller();</code>
+<code>parent::CI_Controller();</code>
 
 <p>The reason this line is necessary is because your local constructor will be overriding the one in the parent controller class so we need to manually call it.</p>
 
@@ -338,11 +338,11 @@
 
 <code>
 &lt;?php<br />
-class <kbd>Blog</kbd> extends Controller {<br />
+class <kbd>Blog</kbd> extends CI_Controller {<br />
 <br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;function <kbd>Blog()</kbd><br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{<br />
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<var>parent::Controller();</var><br />
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<var>parent::CI_Controller();</var><br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}<br />
 }<br />
 ?&gt;</code>
@@ -351,11 +351,11 @@
 
 <code>
 &lt;?php<br />
-class <kbd>Blog</kbd> extends Controller {<br />
+class <kbd>Blog</kbd> extends CI_Controller {<br />
 <br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;function <kbd>__construct()</kbd><br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{<br />
-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<var>parent::Controller();</var><br />
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<var>parent::CI_Controller();</var><br />
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}<br />
 }<br />
 ?&gt;</code>