Added 'application/vnd.ms-powerpoint' to list of mime types.
diff --git a/system/application/config/mimes.php b/system/application/config/mimes.php
index 225b0a5..a8addb9 100644
--- a/system/application/config/mimes.php
+++ b/system/application/config/mimes.php
@@ -30,7 +30,7 @@
'smil' => 'application/smil',
'mif' => 'application/vnd.mif',
'xls' => array('application/excel', 'application/vnd.ms-excel'),
- 'ppt' => 'application/powerpoint',
+ 'ppt' => array('application/powerpoint', 'application/vnd.ms-powerpoint'),
'wbxml' => 'application/wbxml',
'wmlc' => 'application/wmlc',
'dcr' => 'application/x-director',