Are xbox 360 download codes region locked?

[qnine]

Hi,

Does anyone know if full game codes for xbox 360 are region locked?

I know some digital games from the market are and of course the physical DVDs are too.

Specifically, CoD black ops.

Thanks.

 

[Gideon68]

It was the one time I experienced it. I traded with someone on a US military base in Germany and the code wasn't recognized - I think it was for a Call of Duty game. I called the publisher and they confirmed it.