diff --git a/classes/cache/CacheMemcache.class.php b/classes/cache/CacheMemcache.class.php
index 80d1adfe3..1f07c88d4 100644
--- a/classes/cache/CacheMemcache.class.php
+++ b/classes/cache/CacheMemcache.class.php
@@ -88,8 +88,7 @@ class CacheMemcache extends CacheBase {
 	}
 
 	function truncate() {
-		// not supported on memcached
-		return false;
+		return $this->Memcache->flush();
 	}
 }