What is the AT fluid and filter service interval for '06 ML 350 and '06 ML 500 seeing regular service?

The maintenance booklets that accompanied the vehicles states every 39K miles; the local M-B dealer states every 100K miles?

Which is correct?

After comments such as "AT fluid for life" on the early 722.6 transmissions and M-B evaporators don't leak, I tend not to believe my dealer anymore.

Thanks.