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/core/Output.php b/system/core/Output.php
index 45a82f3..05ace91 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -42,13 +42,13 @@
 		$this->_zlib_oc = @ini_get('zlib.output_compression');
 
 		// Get mime types for later
-		if (defined('ENVIRONMENT') AND file_exists(APPPATH.'config/'.ENVIRONMENT.'/mimes'.EXT))
+		if (defined('ENVIRONMENT') AND file_exists(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
 		{
-		    include APPPATH.'config/'.ENVIRONMENT.'/mimes'.EXT;
+		    include APPPATH.'config/'.ENVIRONMENT.'/mimes.php';
 		}
 		else
 		{
-			include APPPATH.'config/mimes'.EXT;
+			include APPPATH.'config/mimes.php';
 		}