Added missing commas.
diff --git a/system/libraries/Cache/Cache.php b/system/libraries/Cache/Cache.php
index 82657ce..5c9d787 100644
--- a/system/libraries/Cache/Cache.php
+++ b/system/libraries/Cache/Cache.php
@@ -38,9 +38,9 @@
 
 	protected $valid_drivers 	= array(
 		'cache_apc',
-		'cache_dummy'
+		'cache_dummy',
 		'cache_file',
-		'cache_memcached'
+		'cache_memcached',
 		'cache_redis',
 		'cache_wincache'
 	);