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/Upload.php b/system/libraries/Upload.php
index e80049f..3177424 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -945,13 +945,13 @@
 
 		if (count($this->mimes) == 0)
 		{
-			if (defined('ENVIRONMENT') AND is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes'.EXT))
+			if (defined('ENVIRONMENT') AND is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
 			{
-				include(APPPATH.'config/'.ENVIRONMENT.'/mimes'.EXT);
+				include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
 			}
-			elseif (is_file(APPPATH.'config/mimes'.EXT))
+			elseif (is_file(APPPATH.'config/mimes.php'))
 			{
-				include(APPPATH.'config//mimes'.EXT);
+				include(APPPATH.'config//mimes.php');
 			}
 			else
 			{