diff --git a/api/src/Cache/Memcache.php b/api/src/Cache/Memcache.php
index d1f3819b0a..dd24f494d1 100644
--- a/api/src/Cache/Memcache.php
+++ b/api/src/Cache/Memcache.php
@@ -14,7 +14,7 @@
 namespace EGroupware\Api\Cache;
 
 // fix warning in tests, if memcache extension not available
-if (defined('MEMCACHE_COMPRESSED')) define('MEMCACHE_COMPRESSED', 2);
+if (!defined('MEMCACHE_COMPRESSED')) define('MEMCACHE_COMPRESSED', 2);
 
 /**
  * Caching provider storing data in memcached via PHP's memcache extension