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/libraries/Driver.php b/system/libraries/Driver.php
index b942f53..d1925c0 100644
--- a/system/libraries/Driver.php
+++ b/system/libraries/Driver.php
@@ -59,7 +59,7 @@
 					// loves me some nesting!
 					foreach (array(ucfirst($driver_name), $driver_name) as $class)
 					{
-						$filepath = $path.'libraries/'.$lib_name.'/drivers/'.$class.EXT;
+						$filepath = $path.'libraries/'.$lib_name.'/drivers/'.$class.'.php';
 
 						if (file_exists($filepath))
 						{