diff --git a/lib/Cake/Cache/Engine/MemcachedEngine.php b/lib/Cake/Cache/Engine/MemcachedEngine.php
index 3538becb32f..32c27d657e5 100755
--- a/lib/Cake/Cache/Engine/MemcachedEngine.php
+++ b/lib/Cake/Cache/Engine/MemcachedEngine.php
@@ -73,7 +73,7 @@ public function init($settings = array()) {
 			'servers' => array('127.0.0.1'),
 			'compress' => false,
 			'persistent' => true,
-			'persistent_id' => 'mc',
+			'persistentId' => 'mc',
 			'login' => null,
 			'password' => null,
 		);
@@ -87,7 +87,7 @@ public function init($settings = array()) {
 			return true;
 		}
 
-		$this->_Memcached = new Memcached($this->settings['persistent'] ? $this->settings['persistent_id'] : null);
+		$this->_Memcached = new Memcached($this->settings['persistent'] ? $this->settings['persistentId'] : null);
 		$this->_setOptions();
 
 		if (count($this->_Memcached->getServerList())) {
diff --git a/lib/Cake/Test/Case/Cache/Engine/MemcachedEngineTest.php b/lib/Cake/Test/Case/Cache/Engine/MemcachedEngineTest.php
index cc8b614958d..a4539771fd5 100755
--- a/lib/Cake/Test/Case/Cache/Engine/MemcachedEngineTest.php
+++ b/lib/Cake/Test/Case/Cache/Engine/MemcachedEngineTest.php
@@ -98,7 +98,7 @@ public function testSettings() {
 			'probability' => 100,
 			'servers' => array('127.0.0.1'),
 			'persistent' => true,
-			'persistent_id' => 'mc',
+			'persistentId' => 'mc',
 			'compress' => false,
 			'engine' => 'Memcached',
 			'login' => null,