diff --git a/apps/user_ldap/lib/connection.php b/apps/user_ldap/lib/connection.php
index c4e4efd048..7fbabda710 100644
--- a/apps/user_ldap/lib/connection.php
+++ b/apps/user_ldap/lib/connection.php
@@ -52,7 +52,7 @@ class Connection extends LDAPUtility {
 		$this->configID = $configID;
 		$this->configuration = new Configuration($configPrefix,
 												 !is_null($configID));
-		$memcache = new \OC\Memcache\Factory();
+		$memcache = \OC::$server->getMemCacheFactory();
 		if($memcache->isAvailable()) {
 			$this->cache = $memcache->create();
 		} else {
diff --git a/lib/private/memcache/apc.php b/lib/private/memcache/apc.php
index e995cbc526..332bbfead0 100644
--- a/lib/private/memcache/apc.php
+++ b/lib/private/memcache/apc.php
@@ -9,15 +9,8 @@
 namespace OC\Memcache;
 
 class APC extends Cache {
-	/**
-	 * entries in APC gets namespaced to prevent collisions between owncloud instances and users
-	 */
-	protected function getNameSpace() {
-		return $this->prefix;
-	}
-
 	public function get($key) {
-		$result = apc_fetch($this->getNamespace() . $key, $success);
+		$result = apc_fetch($this->getPrefix() . $key, $success);
 		if (!$success) {
 			return null;
 		}
@@ -25,26 +18,22 @@ class APC extends Cache {
 	}
 
 	public function set($key, $value, $ttl = 0) {
-		return apc_store($this->getNamespace() . $key, $value, $ttl);
+		return apc_store($this->getPrefix() . $key, $value, $ttl);
 	}
 
 	public function hasKey($key) {
-		return apc_exists($this->getNamespace() . $key);
+		return apc_exists($this->getPrefix() . $key);
 	}
 
 	public function remove($key) {
-		return apc_delete($this->getNamespace() . $key);
+		return apc_delete($this->getPrefix() . $key);
 	}
 
 	public function clear($prefix = '') {
-		$ns = $this->getNamespace() . $prefix;
-		$cache = apc_cache_info('user');
-		foreach ($cache['cache_list'] as $entry) {
-			if (strpos($entry['info'], $ns) === 0) {
-				apc_delete($entry['info']);
-			}
-		}
-		return true;
+		$ns = $this->getPrefix() . $prefix;
+		$ns = preg_quote($ns, '/');
+		$iter = new \APCIterator('user', '/^' . $ns . '/');
+		return apc_delete($iter);
 	}
 
 	static public function isAvailable() {
diff --git a/lib/private/memcache/apcu.php b/lib/private/memcache/apcu.php
index dac0f5f208..7f780f3271 100644
--- a/lib/private/memcache/apcu.php
+++ b/lib/private/memcache/apcu.php
@@ -9,13 +9,6 @@
 namespace OC\Memcache;
 
 class APCu extends APC {
-	public function clear($prefix = '') {
-		$ns = $this->getNamespace() . $prefix;
-		$ns = preg_quote($ns, '/');
-		$iter = new \APCIterator('user', '/^'.$ns.'/');
-		return apc_delete($iter);
-	}
-
 	static public function isAvailable() {
 		if (!extension_loaded('apcu')) {
 			return false;
diff --git a/lib/private/memcache/cache.php b/lib/private/memcache/cache.php
index 0ad1cc7ec0..03671b3f24 100644
--- a/lib/private/memcache/cache.php
+++ b/lib/private/memcache/cache.php
@@ -18,7 +18,7 @@ abstract class Cache implements \ArrayAccess {
 	 * @param string $prefix
 	 */
 	public function __construct($prefix = '') {
-		$this->prefix = \OC_Util::getInstanceId() . '/' . $prefix;
+		$this->prefix = $prefix;
 	}
 
 	public function getPrefix() {
diff --git a/lib/private/memcache/factory.php b/lib/private/memcache/factory.php
index fde7d94756..334cf9a1f0 100644
--- a/lib/private/memcache/factory.php
+++ b/lib/private/memcache/factory.php
@@ -8,7 +8,21 @@
 
 namespace OC\Memcache;
 
-class Factory {
+use \OCP\ICacheFactory;
+
+class Factory implements ICacheFactory {
+	/**
+	 * @var string $globalPrefix
+	 */
+	private $globalPrefix;
+
+	/**
+	 * @param string $globalPrefix
+	 */
+	public function __construct($globalPrefix) {
+		$this->globalPrefix = $globalPrefix;
+	}
+
 	/**
 	 * get a cache instance, will return null if no backend is available
 	 *
@@ -16,6 +30,7 @@ class Factory {
 	 * @return \OC\Memcache\Cache
 	 */
 	function create($prefix = '') {
+		$prefix = $this->globalPrefix . '/' . $prefix;
 		if (XCache::isAvailable()) {
 			return new XCache($prefix);
 		} elseif (APCu::isAvailable()) {
diff --git a/lib/private/server.php b/lib/private/server.php
index 2cbd37a97d..c9e593ec2e 100644
--- a/lib/private/server.php
+++ b/lib/private/server.php
@@ -138,6 +138,10 @@ class Server extends SimpleContainer implements IServerContainer {
 		$this->registerService('UserCache', function($c) {
 			return new UserCache();
 		});
+		$this->registerService('MemCacheFactory', function ($c) {
+			$instanceId = \OC_Util::getInstanceId();
+			return new \OC\Memcache\Factory($instanceId);
+		});
 		$this->registerService('ActivityManager', function($c) {
 			return new ActivityManager();
 		});
@@ -297,6 +301,15 @@ class Server extends SimpleContainer implements IServerContainer {
 		return $this->query('UserCache');
 	}
 
+	/**
+	 * Returns an \OCP\CacheFactory instance
+	 *
+	 * @return \OCP\CacheFactory
+	 */
+	function getMemCacheFactory() {
+		return $this->query('MemCacheFactory');
+	}
+
 	/**
 	 * Returns the current session
 	 *
diff --git a/lib/public/icachefactory.php b/lib/public/icachefactory.php
new file mode 100644
index 0000000000..874f1ec0a5
--- /dev/null
+++ b/lib/public/icachefactory.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * Copyright (c) 2014 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Affero General Public License version 3 or
+ * later.
+ * See the COPYING-README file.
+ */
+
+namespace OCP;
+
+interface ICacheFactory{
+	/**
+	 * Get a memory cache instance
+	 *
+	 * All entries added trough the cache instance will be namespaced by $prefix to prevent collisions between apps
+	 *
+	 * @param string $prefix
+	 * @return \OCP\ICache
+	 */
+	public function create($prefix = '');
+
+	/**
+	 * Check if any memory cache backend is available
+	 *
+	 * @return bool
+	 */
+	public function isAvailable();
+}
diff --git a/lib/public/iservercontainer.php b/lib/public/iservercontainer.php
index b958d2d03f..5473f3ee33 100644
--- a/lib/public/iservercontainer.php
+++ b/lib/public/iservercontainer.php
@@ -141,6 +141,13 @@ interface IServerContainer {
 	 */
 	function getCache();
 
+	/**
+	 * Returns an \OCP\CacheFactory instance
+	 *
+	 * @return \OCP\ICacheFactory
+	 */
+	function getMemCacheFactory();
+
 	/**
 	 * Returns the current session
 	 *