1333 memory?

Looks like it doesn't.

http://www.apple.com/macbook/specs.html

It will work at 1333, but you will have higher latencies and you will lose the 1:2 fsb:ram ratio. And it will overheat so you should use an 1066MHz ddr3 ram.

thank you for the advice of overheat.

I just installed 4 GB of 1333 MHz DDR3 ram in a Macbook 6.1 (2009, Core 2 duo 2.26 MHz). It's running at 1333 MHz without problems so far.

Will let you know if there is overheating or any other issue... I hope not!!!