diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
index 68d9633..c0200aa 100644
--- a/system/libraries/Cache/drivers/Cache_redis.php
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -107,7 +107,7 @@
 		{
 			$data = serialize($data);
 
-			if (($index_key = array_search($id, $this->_serialized)) === FALSE)
+			if (($index_key = array_search($id, $this->_serialized, TRUE)) === FALSE)
 			{
 				$this->_serialized[] = $id;
 			}
@@ -116,7 +116,7 @@
 		}
 		else
 		{
-			if (($index_key = array_search($id, $this->_serialized)) !== FALSE)
+			if (($index_key = array_search($id, $this->_serialized, TRUE)) !== FALSE)
 			{
 				unset($this->_serialized[$index_key]);
 			}
@@ -139,7 +139,7 @@
 	 */
 	public function delete($key)
 	{
-		if (($index_key = array_search($key, $this->_serialized)) !== FALSE)
+		if (($index_key = array_search($key, $this->_serialized, TRUE)) !== FALSE)
 		{
 			unset($this->_serialized[$index_key]);
 		}