Until Turck MMCache updates (if ever), I would use Zend Optimizer, it works pretty well. You should, however, get the newer version 2.5.3 from
http://www.zend.com/store/products/zend-optimizer.php. Xampp 1.4.5 currently comes with 2.5.2, which has some bugs with my current version of Windows (Windows XP Professional SP2). I still like Turck MMCache better, but for now, Zend Optimizer is better than nothing. Oh yeah, I installed it to C:\xampp\php\Zend\, if anyone was interested.