Removing internal references to the EXT constant.  Additionally, marked the constant as deprecated.  Use ".php" instead. Also adding upgrade notes from 2.0.2 to 2.0.3.
diff --git a/system/database/DB.php b/system/database/DB.php
index 8bf1ba8..33207d8 100644
--- a/system/database/DB.php
+++ b/system/database/DB.php
@@ -28,11 +28,11 @@
 	if (is_string($params) AND strpos($params, '://') === FALSE)
 	{
 		// Is the config file in the environment folder?
-		if ( ! defined('ENVIRONMENT') OR ! file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/database'.EXT))
+		if ( ! defined('ENVIRONMENT') OR ! file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/database.php'))
 		{
-			if ( ! file_exists($file_path = APPPATH.'config/database'.EXT))
+			if ( ! file_exists($file_path = APPPATH.'config/database.php'))
 			{
-				show_error('The configuration file database'.EXT.' does not exist.');
+				show_error('The configuration file database.php does not exist.');
 			}
 		}
 		
@@ -116,11 +116,11 @@
 		$active_record = $active_record_override;
 	}
 
-	require_once(BASEPATH.'database/DB_driver'.EXT);
+	require_once(BASEPATH.'database/DB_driver.php');
 
 	if ( ! isset($active_record) OR $active_record == TRUE)
 	{
-		require_once(BASEPATH.'database/DB_active_rec'.EXT);
+		require_once(BASEPATH.'database/DB_active_rec.php');
 
 		if ( ! class_exists('CI_DB'))
 		{
@@ -135,7 +135,7 @@
 		}
 	}
 
-	require_once(BASEPATH.'database/drivers/'.$params['dbdriver'].'/'.$params['dbdriver'].'_driver'.EXT);
+	require_once(BASEPATH.'database/drivers/'.$params['dbdriver'].'/'.$params['dbdriver'].'_driver.php');
 
 	// Instantiate the DB adapter
 	$driver = 'CI_DB_'.$params['dbdriver'].'_driver';